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HISTORY    AND   METHOD 


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OXFORD  UNIVERSITY  PRESS 

LONDON  EDINBURGH  GLASGOW  NEW  YORK 

TORONTO      MELBOURNE      CAPE  TOWN      BOMBAY 

HUMPHREY  MILFORD 

PUBUSHER  TO  THE  UKIVEBSITY 


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Mosaic  from  Populonium  (Etruria).    Probably  1st  Cent.  A.D. 


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STUDIES 


IN   THE 


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HISTORY   AND   METHOD 

OF   SCIENCE 


EDITED  BY 


CHARLES    SINGER 


VOL.    II 


OXFORD 

AT    THE    CLARENDON    PRESS 

1921 


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> 


TO    THE    MEMORY 
OF 

WILLIAM   OSLER 


PREFACE 

The  first  volume  of  this  series  appeared  in  the  autumn  of 
1917.  The  editor  was  unable  to  see  it  through  the  press  owing 
to  his  absence  from  England  on  military  duty.  A  Preface  was 
accordingly  provided  by  Sir  William  Osier,  who,  unhappily,  has 
not  lived  to  see  the  growing  success  that  has  attended  the  ideas 
he  expressed  there  with  so  much  force,  and  towards  which  he 
contributed  life-long  thought  and  effort. 

The  volume  was  received  with  an  approval  that  far  surpassed 
the  hopes  of  its  editor  and  the  issue  was  rapidly  exhausted.  In 
the  present  collection  an  endeavour  has  been  made  to  avoid  some 
defects  inevitable  in  the  earlier  volume.  The  undue  prominence 
given  to  mediaeval  studies  will  be  found  in  part  corrected  and 
care  has  been  taken  to  give  more  space  to  the  evolution  of  the 
mathematical  and  exact  sciences,  though  the  balance  is  yet  far 
from  being  fully  redressed. 

Among  the  many  recent  signs  of  public  interest  in  this  country 
in  the  History  and  Philosophy  of  Science  special  note  must  be  made 
of  the  systematic  course  in  the  subject  now  organized  at  University 
College,  London.  The  work  is  under  the  general  direction  of 
Dr.  A.  Wolf.  Professors  Sir  William  Bragg,  Flinders  Petrie, 
W.  M.  Bayliss,  L.  N.  G.  Filon,  J.  P.  HiU,  F.  G.  Donnan,  E.  J. 
Garwood,  T.  L.  Wren,  D.  Orson  Wood,  and  the  Editor  of  this  series 
are  taking  part  in  it.  The  course  at  Edinburgh  in  the  History  of 
Medicine,  initiated  by  Dr.  J.  D.  Comrie,  has  attracted  a  large  and 
annually  increasing  number  of  students.  Mr.  A.  E.  Heath,  Senior 
Lecturer  on  Education  at  Liverpool  University,  is  giving  systematic 
instruction  there  on  the  History  of  Science,  and  the  Editor  of  this 
series  has  become  Lecturer  in  the  History  of  Medicine  at  University 
College,  London,  and  University  Lecturer  in  the  History  of  the 
Biological  Sciences  at  Oxford.  Great  service  has  been  rendered  by 
Mr.  F.  S.  Marvin,  who  has  not  only  done  much  to  popularize  the 


viii  rjlKFAOK 

History  of  Science,  but  has  sought  to  integrate  this  important  aspect 
of  human  development  in  the  historical  instruction  of  seh(jols. 

Considerable  Hteraiy  activity  is  also  being  exhibited.  The 
Knglish  translation  of  Aristotle  under  the  general  editorship  of 
Mr.  W.  D.  lloss  has  continued  to  appear,  as  has  also  the  much- 
needed  publication  of  Roger  Jiacon's  works  under  the  editorship 
of  Mr.  A.  G.  Little,  Mr.  Robert  Steele,  and  Dr.  Withington.  Sir 
Arthur  Hort  has  rendered  the  History  of  Plants  of  Theophrastua 
into  English,  and  a  similar  service  has  been  done  for  Galen's 
short  treatise  On  the  Natural  Faculties  by  Dr.  A.  J.  Brock. 
A  valuable  work  in  a  different  department  is  Sir  Norman  Moore's 
monumental  and  learned  History  of  St.  Bartholomew's  Hospital. 

All  historians  of  science  look  forward  with  lively  interest  to  the 
appearance  of  Sir  T.  L.  Heath's  History  of  Greek  Mathematics^ 
Professor  Dobson  and  Mr.  Brodetsky's  version  of  Copernicus, 
Mr.  W.  H.  S.  Jones's  edition  of  Hippocrates,  Professor  William 
Wright  and  Mr.  Foate's  translation  of  Vesalius,  and  to  further 
communications  from  the  pen  of  Dr.  J.  K.  Fotheringham,  whose 
work  peculiarly  illustrates  the  aid  rendered  to  modem  scientific 
investigation  by  a  wide  and  deep  knowledge  of  ancient  science. 
Less  conspicuous  but  very  real  and  useful  will  be  the  results  of 
the  tireless  devotion  which  Dr.  Withington  has  for  many  years 
bestowed  on  the  vast  mass  of  Greek  scientific  literature,  with  the 
object  of  rendering  the  forthcoming  edition  of  Liddell  and  Scotfs 
Greek  Lexicon  more  complete  in  what  has  been  hitherto  a  some- 
what neglected  department.  It  is  a  legitimate  hope  that  his 
unique  experience  may  now  be  utiHzed  in  rendering  accessible  to 
English  readers  the  more  important  works  of  Galen. 

Mrs.  Singer's  catalogue  of  early  scientific  MSS.  in  this  country  is 
now  in  a  serviceable  state  and  freely  open  to  students.  It  is  a  card 
index  with  about  forty  thousand  entries  arranged  by  subject.  The 
first  section,  Alchemy,  is  being  printed  as  the  opening  fascicule 
of  an, international  catalogue  of  Alchemical  MSS.,  issued  by  the 
Union  Academique  Internationale  under  the  general  editorship  of 
Professor  Bidez  of  Ghent.      The   next  of   Mrs.  Singer's  sections 


PREFACE  ix 

to  appear  will  probably  be  '  Anatomy '  and  '  Aristotle '  by  the 
Editor  of  this  series. 

Of  foreign  workers  in  our  field  mention  must  be  made  in  the 
first  place  of  the  veteran  scholar  Professor  K.  Sudhoff  of  Leipzig, 
who  has  for  many  years  been  producing  volume  after  volume  of 
highly  original  researches,  covering  wide  stretches  in  the  history 
of  science.  His  extraordinary  fertility  and  equally  great  literary 
generosity  lay  all  other  workers  in  his  department  under  a  debt  of 
gratitude  impossible  to  repay.  It  is  gratifying  to  observe  that  his 
venerable  colleagues,  Professor  Eilhard  Wiedemann  of  Erlangen 
and  Professor  J.  Hirschberg  of  Berlin,  are  still  prosecuting  their 
researches  in  Oriental  Science  and  the  History  of  Optics,  and  that 
fascicules  of  the  Corpus  Medicorum  Graecorum  and  Corpus  Medi- 
corum  Latinorum  continue  to  appear,  though  all  too  slowly.  The 
recent  output  by  Professor  Max  Wellmann  on  the  science  of 
classical  antiquity  has  been  very  remarkable.  Another  useful 
work  in  the  department  of  the  History  of  Science  is  Professor 
E.  O.  von  Lippmann's  Entstehung  und  Ausbreitung  der  Alchewde, 

In  Austria  the  activities  of  the  most  philosophical  of  living 
medical  historians,  Professor  Neuburger,  have  continued  in  spite 
of  the  terrible  conditions  through  which  the  city  of  Vienna  has 
passed  and  is  passing.  The  first  volume  of  his  illuminating  History 
of  Medicine  was  rendered  into  English  by  Dr.  Ernest  Playf air,  with 
the  encouragement  of  Sir  William  Osier.  The  appearance  of  the 
second  volume  of  this  translation  was  a  cherished  wish,  as  it  would 
be  a  suitable  memorial,  of  that  lover  of  learning. 

The  recent  output  in  the  History  of  Science  of  some  of  the 
smaller  European  States  has  of  late  years  been  truly  remarkable, 
and  the  world  owes  to  them  a  number  of  works  of  primary  value 
for  the  subject,  elaborately  published  at  vast  expense.  The 
decipherment,  transcription,  translation,  and  publication  of  the 
beautiful  Windsor  Quaderni  d'Anatornia  of  Leonardo  have  now 
been  completed  by  Professors  Fonahn,  Hopstock  and  Vangensten, 
and  the  work  has  been  published  at  Christiania.  The  Societe 
Hollandaise   des   Sciences   is   proceeding   with   the   monumental 


X  rjlKFACE 

(iditioii,  colUutU'd  from  manuHcript  Hoiirce.s,  of  tlic  (Kuvres  complies 
of  ( 'luistiaaii  Huy^ciis.  DciimarU  has  ^ivcn  us  tho  Opera  Philo- 
."iop/iica  of  .Steusen,  editod  by  l)i-.  Xilliclm  Maar,  the  Opera  Omma 
of  Tycho  Brahe,  edited  by  Dr.  .1.  L.  K.  Dreyer,  and  the  Scientific 
Papers  of  H.  C.  Orsted  ;  all  three  arc  produced  by  the  r'arlsberg- 
foiid.  Professor  Heiberg  of  C.'openhagcn  continues  his  sei'ies  of 
line  works  on  Creek  science,  and  his  writings  are  an  additional 
adornment  of  the  Danish  School.  The  Union  Astronomique 
Internationale,  founded  at  Brussels  in  1919,  has  appointed  a 
Commission  de  reedition  d'ouvrages  anciens. 

In  Italy  the  history  of  science  has  now  been  placed  on  a  firm 
academic  basis.  The  work  of  Professor  Antonio  f'avaro  on  the 
physics  and  mathematics  of  the  seventeenth  century  and  of 
Professor  Piero  Giacosa  on  mediaeval  science  continues.  The 
new  Archivio  di  Storia  dell  a  Scienza  has  completed  its  first  annual 
volume  under  the  editorship  of  Professor  Aldo  Mieli. 

In  France,  since  the  appearance  of  Adam  and  Tannery's  edition 
of  the  Works  of  Descartes  and  the  termination  by  death  of  the 
labour's  of  Henri  Poincare,  the  most  important  publication  has 
probably  been  the  fifth  and  posthumous  volume  of  Pierre  Duhem's 
very  valuable  Le  systeme  du  monde,  histoire  des  doctrines  cosmo- 
logiques  de  Platon  a  Copernic.  Mention  must  also  be  made  of  the 
very  scholarly  work  on  the  Commentaires  de  la  Faculte  de  Medecine 
de  rUniversite  de  Paris  (1395-1516)  by  Dr.  Ernest  Wickersheimer, 
who  has  since  become  librarian  of  the  University  of  Strassburg. 

Nowhere,  perhaps,  has  more  general  interest  been  taken  in  the 
History  of  Science  than  in  the  United  States.  Many  courses 
of  lectures  have  been  devoted  to  the  subject ;  much  valuable 
original  work  in  the  department  of  mathematics  has  appeared 
from  the  pens  of  Professors  L.  C.  Karpinski  and  Eugene  Smith, 
in  medicine  from  Colonel  Garrison  and  Dr.  E.  C.  Streeter,  and 
in  bibliograph}^  from  Dr.  A.  C.  Klebs.  Among  recent  American 
publications  are  Mr.  T.  0.  Wedel's  work.  The  mediaeval  attitude 
toward  astrology,  and  a  useful  translation  of  Choulant's  History 
of  Anatomic  Illustration,  annotated  and  brought  up  to  date  by 


PREFACE  xi 

Mortimer  Frank,  whose  death  at  the  age  of  forty-four  is  a  real 
loss  to  learning. 

Dr.  George  Sarton  has  been  carrying  on  at  Harvard  the  labours 
commenced  before  the  war  in  Belgium.  His  journal,  I  sis,  which 
first  appeared  in  1913  as  a  '  Revue  consacree  a  I'histoire  et 
a  I'organisation  de  la  science  et  de  la  civihsation  ',  has  revived 
since  the  peace,  and  some  form  of  joint  pubhcation  is  projected 
between  this  series  and  I  sis.  Moreover,  in  the  future,  the  Studies 
in  the  History  and  Method  of  Science  will  appear  regularly  as  an 
annual  volume. 

A  central  institute  and  library,  devoted  to  the  promotion  of 
systematic  investigation  into  the  historical  documents  of  science,  is 
greatly  needed  in  this  country.  Such  a  foundation  would  do  much' 
to  place  the  subject  on  its  proper  academic  basis  and  would  rapidly 
react  on  the  whole  system  of  scientific  education.  It  would  help 
the  teacher  to  present  the  sciences  in  their  evolutionary  relation 
to  each  other  and  to  the  course  of  history  as  a  whole.  It  would 
especially  help  the  teacher  of  science  to  develop  his  subject  as 
the  product  of  a  progressive  revelation  of  the  human  spirit  rather 
than  as  a  mere  description  and  attempted  explanation  of  the 
phenomena.  We  may  well  look  to  this  new  orientation  of  scientific 
teaching  to  counteract  the  effects  of  the  regrettable  but  real 
dechne  in  the  study  of  the  older  '  humanities  '. 

CHARLES  SINGER. 

University  College,  London, 
February^  1921. 


CONTENTS 

PAGE 

I.     CHARLES  SINGER 

Greek  Biology   and    its    Relation    to    the 

Rise  of  Modern  Biology        .         .         .         1      "^ 

II.     J.  L.  E.  DREYER 

Mediaeval  Astronomy  .         .         .         .         .     102    :> 

III.  ROBERT  STEELE 

Roger  Bacon  and  the  State   of  Science  in 

the  Thirteenth  Century        .         .         .     121     o 

IV.  H.  HOPSTOCK 

Leonardo  as  Anatomist.     Translated  from  the 

Norwegian  by  E.  A.  Fleming      .  .  .151 

V.     E.  T.  WITHINGTON 

The  Asclbpiadae  and  the  Priests  of  Asclepius     192 

VI.     J.  J.  FAHIE 

The  Scientific  Works  of  Galileo  (1564-1642). 

With  some  account  of  his  life  and  trial         .     206      0 

VIL     F.  J.  COLE 

The  History  of  Anatomical  Injections        .     285    O 

VIIL     F.  S.  MARVIN 

Science  and  the  Unity  of  Mankind    .         .     344 

IX.     F.  C.  CONYBEARE 

Four  Armenian   Tracts   on   the   Structure 

OF  THE  Human  Body       ....     359 


xiv  CONTENTS 

PAGE 

X.     CHARLKS  SIN(;KR 

Steps  leading  to  the  Invention  of  the  First 

Optical  Apparatus.         ....     385 

^       XT.     F.  C.  S.  SCHILLER 

Hypotiiesls    .......     414 

O     XII.     J.  W.  JENKTNSON 

Science  and  Metaphysics      ....     447 

XIIL     E.  A.  NEWELL  ARBER 

A  Sketch  of  the  History  of  Palaeobotany    473 

XIV.     J.  M.  CHILD 

Archimedes'  Principle  of  the  Balance,  and 

some  Criticisms  upon  it  .         .         .     490 

XV.     ARTHUR  PLATT 

Aristotle  on  the  Heart       .         .         .         .521 

APPENDIX  TO  ARTICLE  X 533 

INDEX 535 


']> 


LIST    OF    PLATES 


GREEK  BIOLOGY  AND  ITS  RELATION  TO  THE  RISE  OF 
MODERN  BIOLOGY 

PLATE  FACING  PAGE 

I.  Mosaic  from  Populonium  (Etruria) :  probably  first  century 

A.D.  (Victoria  and  Albert  Museum)    .  .  Frontispiece 

II.  (a)  Theophrastus :  from  Villa  Albani ;  copy  (second 
century  a.d.  ?)  of  earlier  work.  (6)  Aristotle  :  from 
Herculaneum  ;  probably  fourth  century  B.C.        .  .  4 

III.  Late  Minoan  Gold  Cups  :    from  Vaphio,  about  sixteenth 

century  B.C.  (Athens  Museum)  ....  5 

IV.  Aesculapius  receives  Medical  Art  from  Plato  and  Chiron  ; 

Anglo-Saxon  work,  about  1000  (Cotton  Vitellius  C.  Ill, 

fo.  19  r) 6 

V.   (a)  Orobus  sp.  :    MS.  Bodley  130,  fo.  16  r,  written  1120. 

(6)  Betony  :    early  thirteenth  century  (MS.  Ashmole 

1462,  fo.  12  r).    (c)  Teucrium  Chamaedrys  :  MS.  Bodley 

130,  fo.  16  r,  written  at  St.  Albans  1120     ...  8 

VI.  COrKOC     T P AX YC  =  Sow-thistle  :      fifth-sixth     century 

(Julia  Anicia  MS.,  fo.  315  r) 12 

VII.  0ACIOAOC  =  Seedling  Bean  :   fifth-sixth  century  (Julia 

Anicia  MS.,  fo.  370  i;) 13 

VIII.  (a)  i^mgra  =  Blackberry,    {b)  Hyoscyamus.    {c)  Phinomia  ^ 
Paeony  :    Apuleius,  sixth  century  (Leyden  MS.  Voss. 

Lat.  Q.  9) 16 

IX.  (a)  xafji-qXij  =  Bugle  ?  o.Kavdos  =  Acanthus.      (6)    akKifiiov  = 

Anchusa  officinalis  ?  :   Nicander,  ninth  century  (Paris, 

Bibl.  nat.  sup.  grec  247,  fos.  20  r  and  l^v)  .  .        32 

X.  '  Male  '   and    '  Female  '   Mandrakes  :    Dioscorides,  ninth 

century  (Paris,  Bibl.  nat.  MS.  grec  2179,  fos.  104  r  and 

105  r) 33 

XL  Frontispiece  of  Book  XII  ('  On  Birds  ')  of  Le  Livre  des 
Proprietez  de  Chases,  1482  (Brit.  Mus.  MS.  Reg.  15  E.  iii, 

fo.  llr)  . 38 

XII.  Paintings  by  Edward  Tyson,  made  in  1687  :  (a)  Dissec- 
tion of  Lophius.  (6)  Stomach  of  Gazelle  (MS.  at  the 
Royal  College  of  Physicians,  London,  pp.  41  and  92)  .  39 
XIII.  (a)  Female  argonaut  (from  H.  de  Lacaze-Duthiers,  Archives 
de  Zoologie  experimentale,  1892).  (6)  Male  argonaut 
(from  Heiniich  Miiller,  Zeitschrift  fiir  wissenschaftliche 
Zoologie,  1853) 42 

2391  b 


xvi  LIST    ()l<^    I'LATKS 

I'LATK  FACING  PAOE 

\l\'.    Hctaocotyli/.atioii  (iiom  J.  li.  Vriuiiy,  isf)!)   ...        43 
XV.  Utjoscyamm  niger  :    (a)  Written  at  St,  AlbaiiH  1120  (MS. 
liodlcy    130,  fo.  37  r).     (h)  Writti-ii   in    Kiif^land  early 
thiileenth  eeiitury  (MS.  Slouiie  I!)?"),  fo.  If) /•)  .        50 

W'l.  (a)  irf/f//;rcRr/e  -Way broad -Meadow  IMaiitaiii.  {h)  Hcnne- 
belle  ^Hvnhiinvi  -  Ili/o.scyawu.s  relic  ulutu.s,  a  Meditei- 
raiieaii  si)ecieK  :  Anglo-Saxon  work,  about  1000 
(('otton  Vitellius  (;.   Ill,  foH.  21  v  and  2'S  v)      .  54 

XVII.  {(i)  V etunica  ^Bviony.  {b)  V erminacia  {columharis)  -  Ver- 
bena officinalin  :  A])uleius,  tenth  century,  French  work 
(Paris,  l^ibl.  nat.  MS.  lat.  ()8()2,  fos.  20  v  and  20  v)  .  70 
XVIIl.  (a)  OACIOAOC,  Seedling  Bean.  (/>)  rOrPYAH,  Turnip: 
Dioscorides,  tenth  century  (Phillipps  MS.,  now  in  the 
Pierpont  Morgan  Library,  New  York)         ...        74 

XIX.  (a)  Hyoscyamus  :  English,  about  1200  (MS.  Harley  1585, 
fo.  19  v).  (b)  Plantain  :  Italian,  about  1450  (Brit.  Mus. 
MS.  Add.  17063,  fo.  4  r).  (c)  Dracunculus  :  P^nglish, 
about  1200  (MS.  Harley  1585,  fo.  22  v)       .  .75 

XX.  (a)  Aristolochia.  {b)  Heliotropia  =¥orget-me-noi.  {c)  Ca- 
millea  ^Teasel  :  Apuleius,  sixth  century  (Leyden  MS. 
Voss  Lat.  Q.  9)        .  .  .  .     "^    .  .  .78 

XXL  Dracontea  =Dracunculus  vulgaris,  a  Mediterranean  species  : 

Apuleius,  sixth  century  (Leyden  MS.  Voss  Lat.  Q.  9)         79 
XXII.  Three   figures  of  Dracontea  =  Dracunculus  vulgaris:    (a) 
From  O.  Brunfels,  Herbarum  Vivae  Icones.    (b)  German 
work  of  end  of  twelfth  century   (MS.   Harley  4986, 
fo.  7  v).    (c)  Apuleius,  printed  at  Rome,  1483      .  .        82 

XXIII.  (a)  Crisocantus  =  I  fig  =Ivy ,  flowering  form,     (b)  Cysson^ 

Edera^Yvye--=lyy,  climbing  form  (MS.  Bodley  130, 

fo.  55  r  ;   written  in  St.  Albans  1120)  .  .  .83 

XXIV.  (a)  Centaur  holding  Centaury.     (6)  Mercury  brings  '  Elec- 

tropion  '  to  Homer  :  English,  early  thirteenth  century 
(MS.  Ashmole  1462,  fos.  23  /•  and  26  r)  .  .  .  84 
XXV.  Figures  of  Herb  Betony  from  English  MSS.  :  (a)  Early 
thirteenth  century  (Sloane  1975,  fo.  10  v).  (6)  About 
1000  (Cotton  Vitellius  C.  Ill,  fo.  20  r).  (c)  About  1200 
(Harley  1585,  fo.  14  r) 96 

LEONARDO  AS  ANATOMIST 

XXVI.  (a)  Leonardo  da  Vinci :  from  a  crayon  portrait  by  himself 
at  the  Royal  Library,  Turin.  (6)  Foetus  in  utero  and 
relations  of  membranes  to  uteruie  wall  {Quaderni  V, 
fo.  8  /•) 151 


LIST   OF   PLATES  xvii 

PLATE  FACING  PAGE 

XXVII.  [a)  General  structure  of  uterus  and  sources  of  its  blood 
supply  ;  male  organs  {Quaderni  III,  fo.  I  v).    {b)  Topo- 
graphical anatomy  of  neck  and  shoulder  in  a  thin, 
aged  individusil  {Quaderni  Y,  io.  IS  r)         .  .  .158 

XXVIII.  Bones  of  lower  limb  to  which  wires  are  fitted  to  illustrate 

lines  of  muscular  traction  {Quaderni  V,  fo.  4  r)  .  .      160 

XXIX.  (a)   Ventricles   and  layers  of  head  and  eye  in  section 
{Quaderni  V,  fo.  6  v.)    (6)  Casts  of  cerebral  ventricles 
{Quaderni  V,  fo.  7  r)         .  .  .  .  .  .164 

XXX.  {a)  Dissection  of  triangles  of  neck  {Quaderni  V,  fo.  16r). 
(6)  Dissection  of  foot  ;  nails  replaced  by  claws  {Qua- 
derni Y,  fo.  11  r) 166 

XXXI.  {a)  Dissection  of  coronary  vessels  {Quaderni  II,  fo.  3  v.) 
(6)  Dissection  of  bronchi  and  bronchial  vessels  {Qua- 
derni II,  fo.  1  r)       .  .  .  .  .  .  .      168 

XXXII.  (a)  The  semilunar  valves  {Quaderni  II,  fo.  9  v).    {b)  Glass 
casts  with  valves  to  illustrate  action  of  semilunar  valves. 
Diagrams  of  semilunar  valves  {Quaderni  IV,  fo.  11  v)     170 
XXXIII.  (a)  Details  of  cardiac  anatomy  {Quaderni  V,  fo.  14  r).    (6) 

Blood-vessels  in  inguinal  region  {Quaderni  IV,  fo.  8  r).      170 
XXXTV.  (a)  Right  ventricle,  pulmonary  artery  and  musculi  papil- 
lares   {Quaderni   II,   fo.    12  r).      (6)   Ventricles,   right 
auricle,  and  great  vessels  {Quaderni  II,  fo.  14  r)  .      178 

XXXV.  (a)  The  '  Vessel-tree  '  {Quaderni  V,  fo.  1  r).    (6)  Surface  ana- 
tomy :  lower  limbs  of  man  and  horse  {Quaderni  V,  f  o .  22  r)     1 80 
XXXVI.  {a)    Heart,    great   vessels,    bronchi,    &c.    {Quaderni   III, 
fo.  10  v).    (6)  The  intraventricular  muscle  band  {Qua- 

dernilY,  fo.  13r) 186 

XXXVII.  {a)  Proportions  of  trunk  {Quaderni  VI,  fo.  8  r).     {b)  Pro- 

.   portions  of  head  {Quaderni  VI,  fo.  1  r)     .  .  .190 


THE  ASCLEPIADAE  AND  THE  PRIESTS  OF  ASCLEPIUS 

XXXVIII.  {a)  Hippocrates  :  second  or  third  century  B.C.  (British 
Museum).  (6)  Aesculapius  :  fourth  century  B.C. 
(British  Museum) 192 


THE  SCIENTIFIC  WORKS  OF  GALILEO 

XXXIX.  Galileo  Galilei  :    from  a  portrait  in  the  Bodleian  brought 

from  Florence  in  1661 206 

.    XL.  (a)  Galileo's  Lodestone  and  Military  Compass,     {b)  Gali- 
leo's Telescopes  (Galileo  Museum  at  Florence)     .  .      226 
XLI.  Hall  of  the  Galileo  Museum  in  Florence           .          .  .276 


xviii  T.IST    OF    PLATKS 

'I'lll-:   II  IS  roil  N    i)\'  ANATOMICAL   I  \.l  KCTIONS 

IM.ATK  ■  l'A(  INC    I'A(!K 

XLII.    l*(Miiior  i\v  CJraaf  :    IVoni  llw  first   cdilioii  of  the   /fc  I'sk 

Siphonis,  lOdS 202 

\  LI  II.  (a)  l''r('<l(Mik  Hiiyscli  :  I'loni  tlic  first,  edit  ion  of  his  collected 
works,  1721.  {h)  Alex.uidci  Mom-o.  primus:  \vuu\  liis 
rolloctod  works,  I7H1 \\m 

\LI\'.  (^/) 'riu>  coronary  vchhoIh  injected  hy  lluysch,  1704.  (6)  The 
spleen  of  the  o.x  injected  with  wa.x  hy  William  Stukeley, 

1723 .      324 

XL\'.  {(i)  Testis  injected  with  nieiciM y  from  the  vas  defeicns  hy 
Alhrecht  von  Haller,  1745.  (/>)  Micro-injection  of  the 
mucous  membrane  by  Johann  Nathanael  (..ieberkiihn, 
1745       .  .  .  " 328 

XLVI.  (Jeneral  scheme  of  tlie  lymphatics  of  the  human  body 
based  on  mercury  injections  ])y  William  Cumberland 
C'ruikshaidv  and  his  pui)ils,  1780         ....      330 
XLVII.  Mercury  injection  of  the  lymphatics  of  the  human  colon 

and  abdomen  l)y  Paolo  Mascagni,  1787       .  .  .      340 


A  SKETCH  OF  THE  HISTORY  OF  PALAEOBOTANY 

XLVIII.  Fossil  plants  :    Fig.  1.  Cycadeoidea  etrusca.    Fig.  2.  Litho- 
pteris  ;    Lithosmunda  ;    Lithosmunda  minor  ;    Tricho- 
m,anes    .........     472 

XLIX.  One  of  the  original  Cabinets  belonging  to  John  Woodward, 

the  geologist  ........     474 

L.  Fossil  plants.     Fig.  4.  From  lire's  History  of  Rutherglen 
and  East-Kilbride.    Fig.  5.  Impression  of  plants  from 
a  coal-pit  in  Yorkshire.     Fig.  6.  Palmacites.     Fig.  7. 
Phytolithus  Filicites  (striatus)  =  Alethopteris  lonchitica 
(Schl.).      Fig.    8.    Phytolithus   Plantites   {verrucosus)  — 
Stigmaria  ficoides  (Brongn.)       .....      476 

LI.  Fossil  plants  :  Fig.  9.  Examples  from  Parkinson's  Organic 
Remains  of  a  Former  World  (1804).     Fig.   10.  Phyto- 
lithus tessellatus  =  Sigillaria  tessellata  (Steinh.)  ;   Phyto- 
lithus notatus  =SigiUaria  notata  {Hteinh.)    .  .  .478 
Ln.  Fossil  plants  :    Fig.    11.   Neiiropteris  grangeri,   Brongn.  ; 
Neuropteris  jlexuosa,   Sternb.     Fig.    12.   Filicites   Os- 
mundae  =  Neuropteris  Osmundae  (Artis)      .          .          .     482 
LIII.  Fossil    plants:     Fig.     13.    Trigonocarpum    olivaeforme  ; 
T.  noggerathi.    Fig.  14.  Section  of  '  petrified  conifera  '. 
Fig.  15.  Sections  of  petrified  tissues  ....     484 

LTV.  Portrait  of  William  Crawford  Williamson         .  .  .     486 


LIST   OF   PLATES  xix 

PLATE  ,  ■  FACING   PAGE 

LV.  (a)  Fossil  plants  :  Fig.  17.  Calamostachijs  Binneyana,  from 
a  drawing  by  W.  C.  Williamson  of  the  transverse 
section  of  the  cone  ......     488 


LV.  (/;)  Hornets  drawn  by  Thomas  Mouffet  before  1580  (MS. 

Sloane  4014,  fo.  82  r).     See  p.  51       .  .  .  .      488 

ILLUSTRATIONS   IN   TEXT 

GREEK  BIOLOGY  AND  ITS  RELATION  TO  THi; 
RISE  OF  MODERN  BIOLOGY 

FIGURE  PAGE 

1.  Grampus   and  newly-born  young   (from   Pierre   Belon,   Histoire 

naturelle  des  estranges  poissons,  1551).  .  .  .  .        18 

2.  The  uterus  of  the  porpoise  (from  Pierre  Belon)  .  .  .  .19 

3.  The  skeleton  of  a  man  and  of  a  bird  compared  (from  Pierre  Belon, 

Uhistoire  de  la  nature  des  oyseaiix)  .....        20 

4.  The  order  of  living  things,  put  together  from  the  descriptions 

of  Aristotle  .........        21 

5.  The  young  chick  (from  Fabricius  ab  Aquapendente,  Deformatione 

ovi  et  pulli,  IG04) 25 

fi.  (a)  Ovary  of  a  woman  ;  (6)  ovary  of  a  cow  ;  (c)  follicle  and  ovum 
of  a  sheep  (from  Regnier  de  Graaf's  De  muliervm  organis 
generationi  inservientibus,  1672)     .  .  .  .  .  .27 

7.  Development  of  the  rabbit's  ovum  (from  Regnier  de  Graaf)  .        28 

8.  (a)    Female   Galeus   laevis   opened  to   show   the   gravid   uterus  ; 

(6)  a  uterus  opened  exhibiting  three  foetuses  ;  (c)  a  foetus 
removed  from  the  uterus  (from  Fabricius  ab  Aquapendente,  De 
Formato  Foetu,  1604) 30 

9.  Galeus  laevis,  from  Rondelet's  De  piscibus  marinis,  1554     .  .        32 

10.  Relation  of  yolk  sac  to  umbilical  cord  and  intestine  (after  Stensen's 

diagram  in  Ova  viviparorum  spectantes  observation  es,  1675)         .        33 

1 1.  Embryos  of  two  species  oi^Mustelus  (from  Johannes  Miiller,  Ueber 

den  glatten  Hai  des  Aristoteles,  1842)       .....        35 

12.  Embryo  of  Carcharias  with  umbilical  cord  and  placenta  (from 

Johannes  Miiller) 36 

1 3.  Dissection  of  umbilical  structures  of  a  foetal  Carcharias,  schematic- 

ally represented  (modified  from  Johannes  Miiller)    .  .  .        36 

14.  A  part  of  the  uterus  of  Mustela  laevis,  showing  two  placental 

attachments  (from  Johannes  Miiller)       .  .  .  .  .36 

15.  Diagrammatic  section  of  placenta  of  Mustelus  laevis  (modified 

from  Johannes  Miiller)  .......        37 

16.  The  four  chambers  of  the  stomach  of  a  lamb  (from  Marco  Aurelio 

Severino,  Zootomia  Democritea,  1645)     .....       39 


XX  ILUTSTRATTONS    IN    TKXT 

FKUTRE  PAfSE 

17.  Tlic  ioiir cliamlxrcd  stomiu^h  of  a  h1u'0|)  (afior  Nchomiah   (in^w, 

The  Com  pa  ml  ire  Aiidtomy  of  the  Slowarh  and  (luis  lieffvn,  IfiSl)       40 

IH.  The  |)a|)(>r  iiaiit  iliis,  AnjoiKiiifd  Akjo  (Irotn  lic'loii's  Ilisloirc  iidliirclh' 

(Jrs  rslniiKjes  /)<>issons,  1551)  .  .  .  .        41} 

\[K  20.    Draw  iu}.^  of  the  '  male  argonaut  '  (after  Alhicchl  vow  Kollikri)       44 

21.  I)iss(>ct  ion  of  the  '  male  argonaut  '  (after  Krdlikcr)  .  .        45 

22.  CongrcsH  of  Orlojms  viiltjaris  (as  ohscivcd  in  a  tank  hy   f].   I'aco- 

vitza)  ..........  4(5 

23.  Tlu>  frog-fish  (fioni  Piorro  Bclon's  Dr  aquatilihns.  155.*})        .  4K 

24.  Thv  v\vv,{r]r  organ  of  the  tor])c(lo        ......  41) 

25.  Enlarged   figures    of   the    ])vv    (from    b^ancesoo    Stelluti's   Persia 

IradoHo,   H)30) 5.3 

2().  Herbalists   at   work  on   a   mountain  (from   a  facsimile  in  Piero 

Giacosa's  il/agfisfn  ^Sfaiernitowi,  1901)      .....       59 

27.  Dioscorides  writing  while  Intelligence  holds  the  mandrake  for  the 

artist  to  copy   (restored   from   the  Julia   Anicia   M8.,   about 
A.D.  512) (il 

28.  Discovery   presents    a    mandrake   to   the   physician   DioRcorides 

(restored  from  the  Julia  Anicia  MS.)       .....        02 

29.  The  genealogy  of  the  earliest  manuscript  of  Dioscorides        .  .        03 

30.  '  Chamaepitys '  (from  a  fragment  of  an  eighth -century  Greek  Her- 

barium, Bodl.  E.  19) 05 

31.  Outlines  of  the  mandrake  and  its  gatherers  (traced  from  a  twelfth- 

century  English  Herbarium  in  the  British  Museum  and  a  con- 
temporary Italian  Herbarium)       .  .  .  .  .  .71 

32.  The  plantain  (from  a  thirteenth-century  Herbarium,  Sloane  1975, 

fo.  12  v) 72 

33.  The  plantain  (from  the  Herbarius  latinus,  1484)  ...        72 

34.  Wall-flower  with  dodder.     35.  Yellow  flag.     (From  the  German 

version  of  the  Hortus  Sanitatis,  1485)     .  .  .  .  .73 

36.  The  plantain  (from  Lignamine's  Apuleius,  1483)  ...        75 

37.  Young  dracunculus  ;   seedling  beans  :   seedlings  from  the  '  Syrian 

Garden  '  of  Tethmosis  III  (about  1500  B.C.)  at  Karnak    ,  .        85 

38.  Germination   of   seeds    (from   Nathaniel    Highmore's   History   of 

Generation,  1651)  .  .  .  .  .  .  .  .87 

39.  40.  Supernatural  figures  from  Nineveh  holding  male  inflorescence 

of  date  palm  (from  Layard)  .  .  .  .  .  .        88 

41.  Assur-nasir-pal    (about    885-860   B.C.),    with   winged   attendants 

holding  male  inflorescence  of  date  palm,  performing  ceremony 

of  fertilization  (from  a  bas-relief  now  in  the  British  Museum)    .        89 

42.  The  germination  of  wheat  (from  Malpighi,  Anatome  planianim, 

1676) 90 

43.  The  germination  of  the  bean  (from  Malpighi)      .  ,  ,  .91 


ILLUSTRATIONS   IN   TEXT  xxi 


FIGURE  MEDIAEVAL  ASTRONOMY  page 

1.  Diagram  of  the  three  orbits  of  Sol,  Venus,  and  Mercury  (from 

a  manuscript  of  the  fourteenth  century)  .  .  .  .107 

2.  Diagram  of  the  Earth  and  Spheres  (from  Dreyer,  History  of  the 

Planetary  Systems)       .  .  .  .  .  .  .  .115 

LEONARDO  AS  ANATOMIST 

1.  Leonardo's  use  of  serial  sections        .  .  .  .  .  .162 

2.  An  experiment  of  Leonardo  on  the  heart    .....      179 

THE  SCIENTIFIC  WORKS  OF  GALILEO 

1-3.  Diagrams   of  the   Pulsilogia   (from   Sancto   Santorio,   Methodus 

Vitandorum  Error um  in  Arte  Medica,  1602)    ....  209 

4.  Diagram  illustrating  the  hydrostatic  balance       .  .  .  .212 

5.  Galileo's  thermometer       ........  220 

6.  Diagram  to  illustrate  the  proportions  of  Galileo's  fu-st  telescopes  .  228 

7.  Early  drawings  of  Saturn  (from  the  Systema  Saturnum)        .          .  238 

8.  Title-page  of  Sidereus  Nuncius,  1610          .....  241 

9.  The  moon  as  seen  by  Galileo,  1609-10  (from  Sidereus  Nuncius)     .  245 

10.  Title-page  of  II  Saggiatore,  1623         .  .  .  ...  .271 

11.  Title-page  of  Discorsi  e  Dimostrazioni  Matematiche,  1638      .  .271 

12.  Facsimile  of  design  for  a  pendulum  clock  (drawn  by  Vincenzio  Galilei 

from  his  father's  dictation)  .......     282 

THE  HISTORY  OF  ANATOMICAL  INJECTIONS 

1.  Engraved  title  of  the  first  edition  of  De  Graaf's  De  Usu  Siphonis, 

1668 298 

2.  De  Graaf's  injection  syringe  and  accessories,  1668        .  .  .  299 

3.  Uterus  injected  with  red  wax  by  Jan  Swammerdam,  1671    .  .  302 

4.  Swammerdam's  method  of  injecting  the  small  vessels  of  insects    .  303 

5.  Periosteum  of  the  auditory  ossicles  injected  by  Ruysch,  1697        .  305 

6.  Injection  appliances  of  Caspar  Bartholin,  1679    ....  310 

7.  The  lymphatics  of  the  urogenital  organs  injected  with  mercury 

by  Anthony  Nuck,  1691 312 

8.  Triple  injection  of  the  arteries,  veins,  and  lacteals  of  the  mesentery 

of  the  turtle  by  William  Hewson,  1769  .  .  .        •  .     337 

9.  Apparatus  designed  by  Hercule  Eugene  Straus-Durckheim,  1843       342 

STEPS  LEADING  TO  THE  INVENTION  OF  THE 
FIRST  OPTICAL  APPARATUS 

1.  The  structure  of  the  eye,  reconstructed  from  the  descriptions  of 

Rufus  of  Ephesus  (first  centmy  c.E.)       .....     389 

2.  The  structure  of  the  eye,  after  Alhazen       .....      392 


xxii  ILLUSTIIATIONS    IN     I'lOXT 

KKJl'ICK  »'A(!K 

.'J.   Avicriina'h  diiigraiu   to  explain   I  lie   l<•^^  apparciil    >i/c  ol   <li^laIlt 

object        .........  :{!»:{ 

I.    I)ia;.";iaiii  of  Koj^'cr  Macon  to  illustrate  optii^s  ol  lens  3'.).^) 

.">.    Diagram  ol  Ko^'ci-  liacon  to  illustiatc  ()])ticK  ol  lens      .  ;{!)(> 

0.  Diagram  of  Roger  liacon  to  illuHtiaic  optics  of  hiii  ning-glass  IJ!>7 
7.  Tlie  acition  of  spcc^taclo  lenses,  according  to  Leonardo  .  .  401 
S.  The  structure  of  tlic  eye,  according  to  Jjcouardo  .  .  .  402 
1).  Diagram  of  the  eye,  from  Leonardo,  showing  the  tij)hera  vryfilallina  403 

10.  The  action  of  a  pin-hole  camera,  according  to  Leonardo  403 

11.  A  camera  obscura,  according  to  Leonardo            ....  404 

A  SKETC^H  OF  THE  HISTORY  OF  PALAEOJMJTANY 

1.  Edward  J..lhuyd  (from  an  initial  vignette  in  the  llegiHter  of  Bene- 

factors, Ashmolean  Museum,  1708)         .....  475 


GREEK  BIOLOGY  AND   ITS   RELATION  TO  THE 
RISE   OF   MODERN   BIOLOGY 

By  Charles  Singer 


There  is  an  extreme  affecting  of  two  extremities  :  the  one  antiquity,  the  other 
novelty  ;  wherein  it  seemeth  the  children  of  time  do  take  after  the  nature  and  malice 
of  the  father.  For  as  he  devoureth  his  children,  so  one  of  them  seeketh  to  devour  and 
suppress  the  other ;  while  antiquity  envieth  there  should  be  new  additions,  and 
novelty  cannot  be  content  to  add  but  it  must  deface  :  surely  the  advice  of  the  prophet 
is  the  true  direction  in  this  matter,  State  super  vias  antiquas,  et  videte  quaenam 
sit  via  recta  et  bona  et  ambulate  in  ea.  Antiquity  deserveth  that  reverence,  that 
men  should  make  a  stand  thereupon  and  discover  what  is  the  best  way  ;  but  when  the 
discovery  is  well  taken,  then  to  make  progression.  And  to  speak  truly,  Antiquitas 
saeculi  iuventus  mundi.  These  times  are  the  ancient  times,  when  the  world  is 
ancient,  and  not  those  which  we  account  ancient  ordine  retrogrado,  by  a  computation 
backward  from  ourselves. — Bacon's  Advancement  of  Learning,  v.  1. 


PAGE 


I.  The  Course  of  Ancient  and  of 
Modern  Science  compared  . 


1 


II.  The  Record  of  Ancient  and 
the  Record  of  Modern 
Biology 7 

III.  The  Bases  of  the  Aristotelian 

Biological  System     .      .      .  13 

(a)  Clas.sification    ...  13 

(6)   Phylogeny  ....  20 

-.  (c)   Ontogeny    ....  22 

IV.  Some  Aristotelian  Zoological 

Observations      and      their 
Modern  counterparts     ,      .  29 
(a)  The  Placental  Shark    .  29 
(6)  The  Ruminant  Stomach  38 
(c)  The    Generative    Pro- 
cesses of  Cephalopods    .  39 
{d)  Habits  of  Animals.      .  46 
i.  Fishing-frog  and  Tor- 
pedo     46 

ii.  Bees 50 


PAGE 

V.  The  General  Course  of  Botani- 
cal Knowledge    ....     56 
^    {a)   Botany     among     the 

Greeks 56 

(6)  Botany  in  the  West 
from  the  sixth  to  the 
twelfth  century  (the 
Dark  Ages)  ....  67 
(c)  Botany  in  the  West 
from  the  twelfth  to  the 
fifteenth  century  (the 
Middle  Ages)       .^     .      .     73 

VI.  The  Botanical  Results  of  Theo- 
phrastus  compared  with 
those     of     Early     Modern 

Botanists 79 

(a)  Nomenclature  and 

classification  of  Plants  .     79 
(6)  Generation  and  develop- 
ment of  Plants    ...     83 

(c)  Form  and  structure  of 
Plants 92 

[d)  Habits    and    Distribu- 
tion of  Plants      ...     95 


I.  The  Course  of  Ancient  and  of  Modern  Science  compared 
In  the  pages  which  follow  we  discuss  certain  elements  in 
the  exact,  classified  and  consciously  accumulated  knowledge  of 
Uving  things  possessed  by  the  Greeks.  This  biological  knowledge 
and  the  mode  in  which  it  was  attained  are   well  suited  to  the 

2391  _ 


2  CKKKK    BIOLOGY   AND   ITS   RELATION   TO 

illustration  oi  (iicck  sciciitilic  method,  tor  tlu^  actual  achicvc- 
nuMits  of  the  (jlrcck  iiiiiul  were,  no  Ichk  remarkable  and  perhaps  more 
characteristic  in  Biology  than  in  other  departments  of  j)hysical 
science.  As  a  ])reli miliary  to  the  discussion  we  may  })riefiy 
consider  the  means  available  for  forming  an  estimate;  of  CJreek 
science  as  a  whole,  and  in  doing  this  we  shall  inevitably  compare 
and  contrast  tlie  science  of  antiquity  with  that  of  oui-  ow  ji  time. 

Ever  since  man  has  been  man,  he  has  had  some  control  over 
nature  through  his  power  to  aday)t  liis  instruments  to  make  her 
serve  his  will,  and  it  is  jmssible  to  defiiie  science  in  terms  of  this 
power  and  of  the  knowledge  that  lies  at  the  back  of  it.  But  the 
conscious  formulation  of  theories  to  exjjlain  natural  phenomena, 
and  the  conscious  collection  and  record  of  data  as  a  basis  of  these 
theories,  come  as  a  far  later  phenomenon  in  human  development. 
It  is  this  conscious  and  more  sophisticated  process  to  which,  for 
our  present  purpose,  we  shall  give  the  title  science,  and  science 
so  interpreted  cannot  be  traced  with  certainty  earlier  than  the 
speculations  of  the  Ionian  philosophers  of  the  sixth  century  B.C. 
Greek  science  thus  established  continued  its  course  of  positive 
achievement  until  the  second  or  third  century  of  the  Christian 
era.  Then,  from  causes  which  we  need  not  here  discuss,  it  ceased 
to  be  original,  having  run  a  course  of  some  eight  hundred  years. 

Our  effective  record  begins  with  the  Hippocratic  collection. 
Some  elements  in  this  are  at  least  as  early  as  the  sixth  century  B.C., 
and  it  is  therefore  impossible  that  these  earliest  portions  should 
be  the  work  of  Hippocrates  himself  who  died  in  the  first  half  of 
the  fourth  century.  Nevertheless  Hippocrates  is  almost  certainly 
the  first  scientific  writer  of  whom  we  have  substantial  remains. 
The  latest  original  Greek  scientific  works  were  perhajDS  those  of 
Galen  and  Ptolemy  of  the  end  of  the  second  century  of  the  Christian 
era,  or,  if  we  should  include  mathematics  in  our  scheme,  we  may 
carry  the  period  forward  to  Diophantus  of  the  third  or  even  to 
Theon  of  Alexandria  of  the  fourth  century.^ 

We  may  compare  this  course  with  the  science  of  our  owti  time. 
For  a  thousand  years  and  more  after  the  dowaifall  of  Greek  science, 
the  powers  of  observation  and  the  scientific  imagination  of  man- 
kind seemed  to  sleep,  a  sleep  broken  only  by  disorderly  dreams 
which  either  fitfully  recapitulated  the  past,  or  conjured  up  what 
never  was  and  never  will  be.     At  length,  hoAvever,  Man  awoke  to 

^  Or  perhaps  to  Theon's  daughter  Hypatia,  who  survived  to  the  second  decade 
of  the  fifth  century  and  is  said  to  have  made  original  mathematical  investigations. 


THE  RISE  OF  MODERN  BIOLOGY  3 

look  around  and  to  examine  the  world  into  which  he  had  been  born. 
During  the  long  twilight  of  a  new  dawn  he  had  been  stirring  in 
his  slumber,  but  the  year  1543  gave  full  proof  that  the  night  was 
over  and  he  was  at  last  awake.  In  that  year  appeared  the  two 
works  which  mark  the  real  sunrise  of  modern  science,  the  De 
revolutionibus  orbium  celestium  of  the  Pole,  Nicolaus  Copernicus, 
and  the  De  fabrica  corporis  humani  of  the  Belgian,  Andreas 
Vesalius.  These  two  were  the  first  great  modern  natural  historians 
of  the  Universe  and  of  Man,  of  the  Macrocosm  and  the  Microcosm, 
and  if  any  single  year  be  selected,  1543  has  perhaps  a  better  claim 
than  any  other  to  be  regarded  as  the  birth  year  of  modern  science, 
though  we  shall  see  good  reason  for  assigning  its  conception  to  a 
much  earlier  period. 

Beginning  from  1543  we  are  thus  near  the  end  of  the  fourth 
century  of  modern  science,  and  are  now  at  about  the  middle  of 
the  total  period  of  time  that  Greek  science  had  to  run.  During 
these  four  hundred  years  a  vast  and  ever-growing  mass  of  original 
investigation  has  been  recorded,  and  as  time  has  gone  on  the 
stream  has  grown  ever  broader  and  fuller.  Some  idea  of  its 
enormous  and  unreadable  bulk  may  be  gained  by  a  glance  at  the 
International  Catalogue  of  Scientific  Literature  ^  which,  while  giving 
the  titles  alone  of  original  articles,  consists  each  year  of  seventeen 
closely  printed  volumes.  The  vast  intellectual  effort  which  this 
enormous  output  implies  has  gradually  transformed  our  mode  of 
Ufe,  our  attitude  to  the  world  around  us,  and  even  our  hearts  and 
minds. 

Now  if  we  seek  to  compare  this  extraordinary  movement  and 
its  results  with  its  prototype  of  antiquity,  we  encounter  diffi- 
culties at  the  very  outset.  These  difficulties  of  comparison  lie 
not  so  much  in  the  relative  scantiness  of  the  Greek  record — that 
in  itself  might  be  an  advantage  for  our  purpose — but  rather  in 
the  character  of  that  record.  The  differences  in  the  mode  of 
recording  ancient  and  modern  science  become  explicable  when  we 
consider  certain  differences  in  the  history  of  the  two  systems,  and 
to  their  history  we  therefore  turn. 

The  earliest  science,  in  the  sense  that  we  are  using  the 
word,  arose  in  Asia  Minor  on  the  confines  of  the  great  Eastern 

1  Published  for  the  International  Council  by  the  Royal  Societ}'  of  London. 
First  annual  issue  1902,  last  annual  issue  (\vith  sequence  disturbed  by  the  inter- 
vention of  the  war)  1914-16.  It  is  significant  that  the  number  of  biological 
papers  recorded  in  this  enormous  index  is  double  that  of  the  phyeical  and 
mathematical  combined. 

B  2 


4  (jIKEEK   BIOLOGIV    ASD   1T.S   lUOLAlIOX   TO 

civilizatioiiH.  In  the  social  .sy.stoniH  of  tho  valleys  of  the 
EupiuaU's,  Tigris,  and  Nile  tlicrc  had  accuniiilatfd  a  great  mass  of 
obscTvatioiis,  and  upon  them  rough  generalizations  had  been 
ereeted.  These  generalizations  seem  in  the  main  to  have  })een 
an  evolutionary  product  of  the  'social  cojisciousness ',  rather  than 
tlie  detinite  fruit  of  individual  minds,  ajid  it  is  thus  characteristic 
of  the  science  of  the  ancient  East  that  its  ])roducts  are  anonymous. 
From  all  the  centuries  of  intellectual  activity  of  the  civilizations 
of  Babylon  and  of  Egy[)t,  hardly  even  the  name  of  a  scientific 
discoverer  has  come  down  to  us.  It  was  into  a  great  impersonal 
heritage  that  the  philosophers  of  the  Ionian  cities  were  fortunate 
enough  to  enter  ;  with  it  as  a  basis  they  began  to  engage  upon 
that  active  process  of  cosmical  speculation  that  developed  as 
Greek  pliiloso])hy. 

As  time  went  on,  knowledge  accumulated,  separate  sciences  or 
departments  of  knowledge  were  gradualh'  differentiated  and,  in 
the  course  of  centuries,  these  became  more  and  more  distinct  from 
the  parent  stock  of  philosophy.  Yet  it  is  peculiar  to  Greek 
scientific  thought  that  it  never  loses  direct  touch  with  the  philo- 
sophic stem  from  which  it  sprang.  Whether  we  look  to  such  early 
traces  of  the  scientific  spirit  as  that  of  the  sixth  century  B.C.,  when 
Pythagoras  was  contriving  his  first  formulated  conceptions  of  the 
relations  of  number  to  form,  or  whether  we  consider  the  last  vitally 
original  works  of  Greek  science  in  the  second  century  of  the  Christian 
era,  when  Galen  and  Ptolemy  were  giving  forth  those  ideas  on  the 
structure  of  man  and  of  the  ^^'orld  that  were  to  dominate  Western 
thought  for  a  millennium  and  a  half,  from  end  to  end  Greek  science 
constantly  betrays  its  descent  from  Greek  philosophy. 

Far  different  is  the  ancestry'  of  modern  science.  The  origin 
of  modern  science  will  be  sought  in  vain  in  the  lucubrations  of  the 
philosophers,  who  played  but  a  subordinate  part  in  the  revival  of 
letters.  Copernicus  and  Vesalius  were  dead  before  the  great 
j)hilosophers  of  modern  science,  Francis  Bacon  and  Rene  Descartes, 
had  been  born.  Nor  is  it  a  more  fruitful  task  to  attempt,  as  many 
have  done,  to  draw  a  picture  of  our  scientific  system  as  but  a  rebirth 
of  the  wisdom  of  ancient  Greece,  for  we  must  then  seek  its  origin 
in  the  ^mtings  of  the  men  who  were  the  agents  of  that  rebirth. 
Yet  from  them  we  get  but  little  light.  Science,  as  we  understand 
the  term  to-day,  was  far  from  the  minds  of  the  men  who  made 
the  New  Learning.  The  scholars  of  the  fourteenth  and  fifteenth 
centuries  showed  scant  sympathy  for  the  investigation  of  Nature 


x;  — 


i. 

n 

A 

i^B^^^^^BH^Bt 

^^'■\ 

\ 

1 

^ 

^ 

'^'^^^^P^^^^'^^ 

^^ 

1 

X    T 


"      o 
^     u 


O     "^ 


U 


I'  LAI   !•;     Ill 

All-:  MiNoAN  (ioi.i)  ci'i's.    Ariii;.\s  misi:i:m 


From    \^V  P  H  I  O    about    X  \'  1 1  h    cent.    b.  c. 


THE   RISE   OF  MODERN   BIOLOGY  5 

and  the  humanistic  jjeriod  dominated  by  them  was,  on  the  whole, 
backward  or  at  best  but  retros])ective  in  its  scientific  conceptions. 
Their  thoughts  were  rather  with  the  great  past  of  literature  and 
of  art,  which  they  sought  to  bring  back  to  life. 

It  is  certainly  true  that  there  were  a  few  philosophical  AVTiters 
of  the  later  part  of  this  period  in  whom  can  be  traced  some  con- 
sciousness of  the  value  of  the  experimental  method  :  Nicholas  of 
Cusa  (1401-64),  Pomponazzi  (1462-1525),  Fracastor  (1478  ?- 
1553)  stand  here  to  witness.  But  it  is  far  from  clear  that  their 
ideas  on  the  mode  of  extension  of  natural  knowledge  were  related 
to  the  re-discovery  of  the  Greek  texts  and  the  diffusion  of  know- 
ledge of  the  Greek  language.  These  men,  at  best,  were  few  and 
exceptional,  and  they  come  mainly  in  the  late  and  academic  period 
of  the  learned  revival ;  their  place  is  rather  among  the  founders 
of  modern  science  and  th6y  do  not  naturally  fall  into  the  series 
of  the  scholars  of  the  classical  Renaissance.  It  may,  indeed,  be 
claimed  that  the  astronomical  work  of  Regiomontanus  (1436-76) 
and  Purbach  (1423-61)  was  dependent  on  their  salvage  of  the  text 
of  Ptolemy.^  But  their  recovery  of  the  Greek  original  was  the 
result  of  their  scientific  zeal  and  an  incident  in  their  scientific 
researches  ;  it  did  not  provide  the  primary  stimulus  for  those 
researches. 

If  we  turn  to  the  revival  of  biological  studies,  we  are  encountered 
with  the  same  phenomenon  of  dissociation  from  the  learned  revival 
of  the  Greek  texts.  The  first  modern  records  of  the  close  scientific 
observation  of  plants  or  animals  impinge  on  the  intellectual  orbit 
of  the  age  either  too  early  or  too  late  to  be  explained  as  attracted 
thither  by  the  new  learning.  Effective  advance  in  zoological 
knowledge  hardly  begins  until  the  second  half  of  the  sixteenth 
century,  but  it  was  preceded  by  the  work  of  the  anatomists 
whose  activities  we  may  trace  back  to  the  eleventh  century. 
The  records  of  botanical  observation  tell  much  the  same  tale.  The 
familiar  attempts  of  the  '  fathers  of  Botany '  are  not  encountered 
until  well  into  the  sixteenth  century,  but  behind  their  work  we 
can  discern  a  long  and  slow  evolution  of  first-hand  plant-study 
reaching  back  to  the  twelfth  century.     However  true  it  may  be 

1  Purbach  died  before  his  project  of  obtaining  the  Greek  text  was  attained. 
His  Theoricae  novae  planetarum,  Nuremberg,  1472,  was  published  by  Regiomon- 
tanus and  relies  on  the  text  derived  from  Arabic.  The  Epytoma  loannis  de  monle 
regis  [i.  e.  Regiomontanus]  in  Almagestum  Plolomei,  Venice,  1496,  goes  back 
however  to  the  Greek. 


C.  (JllKIOK    liI()L()(;V    AND    ITS   RELATION   TO 

thill  (Jrcck  tliout^lil  is  the  iinal  iiiotivf  ot  tlii-sc  (Icvclopinciits, 
tliat  the  desire  to  know  is  but  the  stirring  again  of  the  Greek 
spirit  crushed  and  oviThiid  by  harbaiisin  and  nuHunderstanding, 
it  is  yet  clear  tliat  tiie  actual  recovery  of  tiie  texts  liad  no  very 
close  rehition  to  the  reconnnencenient  of  direct  })i()logical  observa- 
tion. Above  all,  we  need  to  distinguish  mere  jjaff.sivc  lacream  of 
knowledge  brought  by  the  revival  of  the  Greek  language  from  the 
active  txlension  of  knowledge  by  direct  observation  that  is  the 
essence  of  the  exi)cri mental  method.  This  [)rocess  of  active  exten- 
sion began  centuries  before  the  learned  Greek  revival  and  received 
its  great  impetus  long  after  it. 

Thus  modern  science  arose  largely  independent  both  of  philo- 
sophy and  of  scholarship.  tShe  was,  in  truth,  conceived  in  obscure 
and  humble  circumstances  before  the  days  of  the  new  learning  and 
in  very  different  surroundings  from  those  of  her  older  sister.  She 
did  not  take  her  origin,  as  did  Greek  science  of  old,  among  a  group 
of  philosophers  thinking  at  large,  and  with  little  to  check  their 
investigations  and  their  speculations  save  the  limits  of  their  own 
intellectual  powers  and  a  slowly  accumulating  mass  of  observa- 
tions. The  lines  of  modern  physical  science  fell  in  far  less  pleasant 
places.  Modern  science  entered  on  her  first  period  of  development 
in  a  highly  sophisticated  society,  ruled  intellectually  by  a  most 
rigid  tradition,  limited  by  the  claims  of  a  priesthood,  and  con- 
stantly checked  by  an  interpretation  of  Scripture  which  was 
only  one  degree  more  fettering  than  the  scholastic  presentation 
of  such  Greek  philosophy  as  had  reached  that  age.  It  was  in 
the  twelfth  or  perhaps  the  early  part  of  the  following  century, 
with  the  flowing  tide  of  the  scholastic  movement,  that  men  began 
consciously  but  very  slowly  to  modify  by  observation  the  details  of 
a  vast  tradition  concerning  the  structure  of  the  universe  and  of  man.^ 

^  Some  reservation,  so  far  as  Anatomy  is  concerned,  must  be  made  for  the 
School  of  Salerno,  where  we  have  evidence  that  animals  were  being  dissected  at 
the  end  of  the  eleventh  century.  There  is,  however,  no  evidence  that  this  example 
was  followed  elsewhere  for  generations,  and  perhaps  the  work  of  Salerno,  so  far 
as  it  is  really  scientific,  is  more  logically  regarded  rather  as  the  last  phase  of  the 
ancient  than  as  the  first  phase  of  modern  science.  The  two  earUest  Salernitan 
anatomies  are  of  the  pig  and  they  date  respectively  from  about  1085  and  1100; 
they  may  be  most  conveniently  consulted  in  Salvatore  De  Renzi,  Collectio  Salerni- 
tana,  5  vols.,  Naples,  1852-9,  vol.  ii,  pp.  388  and  391.  Even  the  earlier  of  these 
two  tracts  shows  some  trace  of  Arabian  influence.  Light  is  thrown  on  these 
early  anatomical  tractates  by  a  recent  excellent  graduation  thesis  of  a  pupil  of 
K.  Sudhofif,  F.  Eedeker,  Die  '  Anatomia  magistri  Xicolai  phisici '  und  ihr 
Verkdltnis  ziir  Anatomia  Chojyhonis  und  Richardi,  LeiiDzig,  1917. 


Platk  IV     Cotton  Vitellius  C.  Ill     fo.  ujr,  Anglo-Saxon  Work  c.  i 


ooo 


lSG0i;=q»^-  pJ^WD  CGMlTWiWS 


PLATO  ^:  CHIRON   HAND  MEDICAL  ART  TO  AESCULAPIUS 

Contrast  typical  Early  English  drawing  of  animals  and  plants  xyith  Classical 
work  of  frontispiece  and  Renaissance  work  of  Plate  XI 


THE   RISE  OF  MODERN  BIOLOGY  7 

The  process  of  development  was  perforce  slow,  for  in  the 
social  and  intellectual  environment  of  the  age  speculation  was 
impossible,  and  the  only  practicable  advance  was  that  of  re- 
peatedly verified  experience.  It  was  easy  to  confine  a  philosopher 
to  his  monastic  cell  for  alleging  aught  new  of  the  constitution  of 
matter  or  of  the  structure  of  the  heavens,  but  less  easy,  even  in 
those  days,  to  deny  that  his  gunpowder  exploded,  when  it  did 
explode,  or  that  his  glasses  magnified,  when  they  did  magnify. 
Princes  and  prelates  had  no  need  of  the  aid  of  Greek  thought  to 
discern  the  advantages  that  they  might  derive  from  the  applica- 
tions of  gunpowder,  nor  did  they  await  the  re-discovery  of  Greek 
letters  to  become  sensible  of  the  uses  of  spectacles.  If  necessity 
is  the  mother  of  invention,  experience  is  her  father,  and  these 
two  rather  than  Greek  letters  and  Greek  philosophy  were  the 
real  begetters  of  the  new  experimental  method.^ 

Perhaps  it  is  in  the  order  of  nature  that  the  root  of  the  tree 
of  knowledge  is  bitter  though  its  fruit  be  sweet ;  it  is  at  least 
true  that  the  lesson  of  scientific  verification  needed  to  be  well 
learnt  before  scientific  speculation  and  theorization  could  become 
profitable.  That  lesson  had  at  last  been  learnt,  and  we  may  be 
assured  that  the  profound  difference  in  the  manner  of  setting  forth 
the  science  of  the  modern  and  that  of  the  ancient  world  is  an 
expression  of  the  historic  difference  in  the  origin  of  the  two 
systems. 

II.  The  Record  of  Ancient  and  the  Record  of  Modern 

Biology 

Consider  examples  of  the  two  methods  concretely  and,  turning 
to  one  of  the  thousands  of  files  of  journals  that  make  up  the 
bulk  of  any  modern  scientific  library,  compare  its  contents  with 
one  of  the  scientific  works  of  Aristotle  or  of  Theophrastus.  Since 
we  are  discussing  Biology,  we  will  select  a  biological  journal 
and  briefly  examine  an  average  article  in  it,  for  such  articles  on 
special  and  narrow  problems  are  a  pecuhar  product  of  modern 
science  and  in  these  '  memoirs  '  modern  science  is  most  charac- 
teristically represented. 

^  In  the  history  of  scientific  development  mathematics  and  the  mathematical 
sciences  stand  somewhat  apart  from  the  other  departments  of  knowledge.  It  is 
a  point  that  cannot  be  treated  here,  but  it  has  been  briefly  discussed  by  the  present 
writer  in  a  pamphlet,  Greek  Science  and  Modern  Science,  a  Comparison  and  a 
Contrast,  London,  1920. 


8  CJJIKKK    BiOLOUY   AK\)  J  I'.S   JtKJ.AlJlJ.N   TO 

Tlie  autlior  hcj^ins  by  ])oiiitiiig  out  a  oaj)  in  knowledge.  The 
structun^  or  Jiabils  of  .some  rare  orgauisin,  he  tellw  us,  are  inade- 
quately kuowji,  or  the  development  of  Home  plant  may  be  expected 
to  throw  light  on  th(^  relationship  between  two  groups  of  jjlants, 
or  perhaps  the  func  tion  of  an  organ  requires  further  elucidation. 
Having  stated  Jiis  problem,  he  reviews  the  efforts  made  l)y  others 
to  illumine  this  dark  place  in  knowledge.  He  points  out  some  of 
their  errors  or  decides  to  accept  their  work  and  base  his  own 
upon  it.  Perha])s  he  distrusts  their  experiments  or  would  like  to 
re-interpret  their  results.  Having  summarized  their  labours  he 
details  his  own  ex])eriments  and  observations. 

But  he  is  not  able  to  tell  us  all  of  these.  Jf  he  did,  scientific 
literature  would  be  far  more  bulky  than  it  already  is  and  science 
would  quickly  perish,  suffocated  under  the  dead  weight  of  its 
own  verbosity.  Our  author  must,  in  fact,  omit  a  great  many  of 
his  mental  processes.  Space  will  not  permit  him  to  tell  us  how 
he  embarked  on  many  different  lines  of  work  and  abandoned  them 
as  unprofitable  or  too  difficult,  nor  anything  of  the  months  or  years 
spent  in  merely  repeating  the  experience  of  others.  He  says  no 
word  of  how  he  acquired  and  improved  his  experimental  skill  and 
technical  experience.  He  tells  merely  of  those  developments  of  his 
work  that  have  yielded  him  results.  But  he  does  not  tell  us  all 
even  of  these.  When  b}^  gradual  steps  he  had  at  last  reached,  or 
perhaps  with  the  instinct  of  genius  had  more  quicklj^  discerned, 
a  profitable  direction  for  his  investigations,  he  reached  after  a  time 
those  conclusions  which  his  final  fine  of  w^ork  has  verified  and 
rendered  more  exact.  It  is  this  final  process  of  verification  that 
he  mainly  describes  in  his  article,  and  it  is  the  details  of  this  that 
occupy  the  bulk,  perhaps  nineteen-twentieths  or  more,  of  all  that  he 
has  to  say.  Then  having  described  these  verificatory  experiments, 
he  summarizes  his  conclusions  in  a  short  paragraph  of  a  few  fines. 

That  is  a  fair  description  of  the  average  piece  of  scientific 
work  as  it  is  turned  out  to-day,  and  from  vast  accumulations  of 
such  work  the  generalizations  of  men  of  scientific  genius  have  been 
mainly  though  sometimes  unconsciously  built  up.  The  mass  of 
scientific  WTitings,  bulky  as  they  are,  contain  descriptions  of  only 
the  verificatory  experiments,  and  it  is  on  account  of  this  necessary 
Umitation  that  it  is  impossible  to  understand  scientific  method 
from  books  without  making  independent  observations. 

How  does  the  science  of  antiquity  compare  wdth  material  such 
as  this  ?    The  Greek  work  is  of  course  less  in  quantity  and  often 


P  X 


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X 


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>. 

iln 

rt 

u: 

THE  RISE  OF  MODERN   BIOLOGY  9 

fragmentary  in  character,  yet  it  is  not  that  which  makes  com- 
parison difficult.  The  difficulty  arises  from  the  habit  of  the 
Greek  writers  of  setting  dow^n  only  their  conclusions.  Their 
methods  of  work,  even  their  verificatory  observations,  they  have 
almost  completely  hidden  from  us.  It  is  as  though  we  had  a  col- 
lection of  the  last  few  lines  of  a  series  of  scientific  articles.  To 
grasp  the  nature  of  modern  scientific  method  from  a  scientific 
article  is  difficult,  since  not  all  the  mental  processes  involved  are 
represented.  In  the  case  of  Greek  science  the  difficulty  is  far 
greater,  for  here  we  have  only  the  conclusions  with  hardly  any 
of  the  processes.  There  survives  to  this  day  a  form  of  scientific 
literature,  or  rather  of  Uterature  on  scientific  topics,  which  bears 
a  distant  analogy  to  some  parts  of  the  Greek  record  as  it  has 
reached  us,  though  its  motive  is  utterly  different.  It  is  the  type 
of  work  known  as  the  '  cram-book ',  which  merely  summarizes  the 
known  or  recognized  facts  without  reference  to  sources  or  methods. 
Such  works  present  us  with  the  final  results  of  vast  amounts  of 
intellectual  effort  but  they  give  little  information  as  to  how  those 
results  have  been  obtained. 

Now  it  would  appear  that  it  is  not  the  accidents  of  time  that 
have  reduced  the  Greek  record  to  its  present  state.  The  responsi- 
bility rests  far  more  with  the  Greeks  themselves  and  with  their 
method  of  research.  The  Greek  scientific  work  lacks  nothing  in 
brilhance,  the  Greek  scientist  yields  to  none  in  keenness,  the 
Greek  record  is  at  least  the  equal  of  our  own  in  clearness.  It  is  the 
constant  solicitude  for  the  exact  mode  of  investigation,  a  solicitude 
characteristic  of  our  own  science,  that  we  so  often  seek  in  vain 
among  the  Greeks.  The  method  of  modern  scientific  research  is 
before  all  things  and  above  all  things  a  process  of  verification. 
'  The  complexity  of  phenomena  ',  says  a  critic  of  Aristotle,  '  is 
as  that  of  a  labyrinth,  and  one  ^vrong  turn  may  cause  the  wanderer 
infinite  perplexity.  Verification  is  the  Ariadne-thread  by  which 
alone  the  real  issue  must  be  sought.'  ^  Yet  the  process  of  verification 
is  slow  and  tedious  and  often  diffic^ilt  and  dull,  and  Man  is  by 
nature  lazy  and  impatient,  hating  labour  yet  eager  for  results. 
Hence  Credulity.  Credulity  is  the  Pandora  of  Science,  promising 
everything,  yielding  nothing.  '  If  you  trust  before  you  try,  you 
may  repent  before  you  die '  is  as  good  a  maxim  in  scientific  as 
in  human  relationships,  yiefxurjao  d-maTelu  would  have  been 
a  salutary  phylactery  for  the  Greek  scientific  Pharisee,  serene  in 

^  G.  H.  Lewes,  Aristotle  :  a  chapter  from  the  history  oj  science,  London,  1864. 


10  (IKKKK    lUOUKiV    AM)    ITS    |{  KI.A TIOX    TO 

the  foiivit'tion  of  tlic  power  of  his  icasoii,  to  liavr  homid  upon  liis 
liaiul  ami  to  have  worn  as  a  troiitlet  between  his  eyes.  It  is  true 
tluit  the  great  Greek  minds  were  singuhirly  free  from  tliat  baser 
credulity  that  we  eall  superstition— from  that  they  were  preserved 
by  tlieir  eonvietion  tluit  order  reigned  in  Nature — but  few  indeed 
were  the  Greeks  who  showed  an  adequate  scientific  scepticism. 
The  Greek  often  accepted  data  without  scrutiny,  induction  without 
proof.  His  very  brilliance  was  a  source  of  weakness  and  he  was 
often  letl  to  believe  that  the  order  of  phenomena  must  perforce 
correspond  to  his  own  admirably  clear  conceptions. 

But  although  Greek  science  failed  to  lay  the  enormous  stress 
on  verification  that  we  in  this  last  age  have  found  to  be  the  chief 
condition  of  scientific  progress,  it  is  yet  certainly  true  that  all 
Greek  scientists  were  not  equally  deficient  in  this  respect.  Aris- 
tarchus  of  Samos,  Archimedes  of  Syracuse,  Hero  of  Alexandria, 
these  are  illustrious  exceptions,  and  the  lasting  value  of  their 
results  remains  the  justification  of  their  method.  Further,  the 
process  of  verification  is  easier  in  some  sciences  than  in  others. 
Such  are  those  purely  observational  studies  classed  under  the 
general  title  of  Natural  History,  for  in  them  the  phenomena  are 
visible  to  all  and  the  difficulty  usually  lies  rather  in  the  collection 
and  arrangement  of  the  vastly  numerous  data  than  in  their  veri- 
fication. Moreover,  biological  phenomena  are  so  exceedingly 
complex  that  it  is  very  difficult  to  form  general  theories  to  explain 
any  considerable  proportion  of  them.  The  Greek  naturalist  was 
thus  less  tempted  than  the  Greek  physicist  or  astronomer  to  fit 
his  facts  to  his  preconceived  theories. 

Yet  even  in  the  field  of  natural  history  the  Greek  character 
had  its  own  special  sources  of  weakness.  The  Greeks  were  gifted 
with  such  a  variety  of  talents  that  there  may  be  a  tendency  to 
credit  them  with  quahties  that  were  not  theirs,  for  although 
extraordinarily  anxious  to  explain  natural  phenomena  they  were 
not  remarkably  observant  of  Nature  except  when  their  attention 
was  specially  drawn  to  it.  It  was  the  world  in  relation  to  himself 
and  not  as  a  mere  objective  complex  of  phenomena  that  interested 
and  appealed  to  the  Greek.  Thus  in  his  attention  to  purely  external 
phenomena  he  ranks  no  higher  than  many  peoples  infinitely  his 
inferiors  in  other  respects.  It  is  said  that  any  Malay  can  distinguish 
some  three  hundred  species  of  insects  ;  set  off  against  this  the 
whole  fauna  of  Aristotle  with  its  total  of  but  five  hundred  and  forty 
forms.     Again,  Theophrastus,  a  professed  botanist,  mentions  only 


THE   RISE   OF  MODERN  BIOLOGY  11 

three  hundred  plants,  practically  all  cultivated  ;  compare  this  to 
the  record  of  barbarian  Anglo-Saxon  speaking  tribes  of  whose 
literature  the  merest  fragment  survives,  but  a  fragment  containing 
about  eight  hundred  plant  names. ^ 

But  when  the  attention  of  the  Greek  was  once  fixed  upon  the 
structure  or  habits  of  living  things,  his  success  in  elucidating  or 
portraying  them  was  unrivalled,  for  then  the  living  things  became 
part  of  his  own  world  and  not  merely  of  the  world  around  him, 
personal  and  not  impersonal.  With  us  it  is  quite  otherwise,  for 
it  is  just  the  impersonal  or  objective  study  that  gives  the  hall-mark 
to  our  science  and  perhaps  also  to  our  art,  and  it  is  exactly  in 
this  objective  or  impersonal  aspect  that  the  Greek  often  failed. 
And  he  well  knew  his  own  weakness,  which  Plato  has  exposed 
for  us  with  a  sure  hand :  '  If  we  consider  ',  he  says,  '  the  works 
of  the  painter  and  the  different  degrees  of  gratification  with 
which  the  eye  of  the  spectator  receives  them,  we  shall  see  that  we 
are  satisfied  with  the  artist  who  is  able  in  any  degree  to  imitate  the 
earth  and  its  mountains,  and  the  rivers,  and  the  woods,  and  the 
universe,  and  the  things  that  are  and  move  therein  ;  and  further, 
that  knowing  nothing  precise  about  such  matters,  we  do  not 
examine  or  analyse  the  painting  ;  all  that  is  required  is  a  sort  of 
indistinct  and  deceptive  mode  of  shadowing  them  forth.  But 
when  he  paints  the  human  form  we  are  quick  at  finding  out 
defects,  and  our  familiar  knowledge  makes  us  severe  judges  of  one 
who  does  not  render  every  point  of  similarity.'  ■  This  criticism 
of  Plato  is  well  borne  out  by  a  study  of  Greek  art. 

If  we  examine  the  attempts  to  represent  the  forms  of  the 
animal  and  vegetable  creations  by  earl}^  peoples,  a  very  striking 
feature  presents  itself.  A  large  number  of  ancient  delineations  of 
animals  and  plants  have  come  down  to  us,  and  these  figures  show 
that  the  habits  and  forms  of  moving  creatures  fixed  the  attention 
of  almost  all  races  long  before  the  same  care  was  expended  on 
plants.  Animals  are  more  like  ourselves  than  plants,  they  move 
and  feel  and  are  subject  to  pleasure  and  passion,  and  so  are 
capable  of  more  personal  treatment.  The  natural  interest  in  the 
animal  rather  than  in  the  plant  might  be  illustrated  by  a  hundred 
instances  from  the  palaeoUthic  cave  paintings  downwards,   but 

1  It  is  true  that  of  these  Early  English  plant  names  many  are  derivetl  from 
Greek  (through  Latin)  and  many  have  only  a  literary  use.  But  even  allowing 
for  these  tendencies  their  number  remains  remarkable. 

2  Critias. 


12  (IIIKKK    KI()I.()(;^'    AM)    ITS    KKLA'I'ION    TO 

\vc  will  liiUc  oiii-  example  IVom  a  pre-Hellenie  people  in  tlie  land 
of  the  ClreeUs,  The  best  known  of  all  the  Minoan  i-elies  are 
l)erhaps  the  N'aphio  c  iips  (IMatc  iii),  and  these  betray  the  most 
careful  study  of  the  structure  and  nioxcnients  of  tjie  hull.  liiH 
anatomy  is  aeeurately  shown  ajid  we  ean  elearly  diseerji  the 
surface  markin<2;s  raised  \)y  tlie  muscles  which  move  the  shoulders 
and  the  hind-quarters,  as  well  as  })y  those  which  su))port  the;  head 
and  control  the  ribs.  Yet  the  representations  of  j)lants  on  these 
cups  are  very  ])oor,  so  that  the  trees  cannot  be  identified. 

This  neglect  of  plants,  the  beings  least  like  ourselves,  is 
characteristic  also  of  the  Hellenic  art  that  succeeded  and 
replaced  the  Minoan,  and  it  has  its  analogue  in  Greek  science. 
In  the  Greek  scientific  writings  the  interest  in  plants  is  usually 
j)ractical ;  even  Theophrastus,  dealing  almost  exclusively  with 
the  domesticated  varieties,  frankly  tells  us  that  it  was  their 
medical  application  that  had  led  to  their  more  accurate  study; 
the  same  is  true  of  Dioscorides  and  of  a  number  of  minor  Greek 
authors  who  have  Avritten  on  plants  and  their  properties.  We 
may  search  classical  art  in  vain  for  any  striking  figures  of  plants, 
and  the  best  represejitations  come  to  us  from  a  time  when  the 
creative  force  of  Greece  was  dead.  The  most  accurate  Greek 
representations  of  plants  are  in  a  series  prepared  by  artists  of 
Constantinople  as  late  as  the  sixth  century  of  the  Christian  era 
(Plates  VI  and  vii).  The  draftsmen  of  the  Julia  Anicia  MS.  of 
about  512  represent  their  originals  faithfully  and  accurately, 
point  by  point,  almost  hair  by  hair,  but  with  no  trace  of  imagina- 
tive treatment.^  These  degenerate  scions  of  the  mighty  race  of 
Pheidias  and  Apelles  were  producing  pictures  of  plants  which 
are  indeed  no  works  of  art  but  are  yet  accurate  and  clear  and 
represent  their  subjects  much  as  the  illustrator  of  a  modern 
scientific  treatise  might  seek  to  do. 

If  we  turn  from  the  graphic  representation  of  living  things  to 
scientific  discourse  about  them  we  find  ourselves  in  face  of  an 
extensive  literature.  Conrad  Gesner,  the  most  learned  of  biolo- 
gists, estimated  the  number  of  Greek  works  with  considerable 
bearing  on  Botany  as  over  a  hundred,  and  although  many  of  these, 
it  must  be  admitted,  are  very  trivial,  yet  about  half  of  them 

1  It  is  true  that  some  of  the  figures  in  this  MS.  and  possibly  all  of  them  are 
copied  from  earlier  MSS.  and  not  directly  from  nature.  But  even  the  originals, 
as  shown  below  (p.  63,  fig,  29),  must  have  been  long  posterior  to  the  best  period 
of  Hellenic,  though  contemporary  with  the  so-called  Augustan  art  with  its  re- 
markable treatment  of  plant  forms. 


PI.ATK    VI 
Julia   Anicia    MS.    fo.  315  r    \'tli  Villi    cent. 


C  O  r  K  O  C    T  P  A  X  Y  C  S  O  \\-  -  T  H  I  S  T  L  E 


.    I'  i.A  r  !■:   \'  I  I 

II  1  i  a     A  11  i  (•  i  a     MS.     I  o.  3  70  \"     \'  I  li     \'  I  I  h     c  c  n  l 


(J)  A  C  I  0  A  O  C  SEEDLING    BEAN 


THE   RISE  OF  MODERN    BIOLOGY  i:>, 

still  find  a  place  in  the  most  exhaustive  modern  history  of  botany/ 
The  number  of  works  on  the  structure  and  habits  of  animals  is 
also  considerable.  Now  if  the  Greek  was  interested  in  men  rather 
than  things,  as  Plato  tells  us,  how  account  for  all  this  outjjut  ? 
What  is  it  that  thus  fixed  the  attention  of  the  Greek  on  animals 
and  plants  ?  The  answer  is  that  these  works  have  in  the  main 
a  practical  end  ;  the  plants  and  animals  are  described  for  the  use 
to  which  they  can  be  put  by  man.  But  there  remains  a  small 
residuum  of  works,  chiefly  those  of  the  Lyceum,  which  have  no 
such  end  in  view.  Why  were  these  written,  and  where  among  the 
self-centred  Greek  people  w^as  the  j^ublic  interested  in  natural 
knowledge  with  no  direct  application  to  the  circumstances  of  hfe  ? 
The  answer  is  that  the  best  Greek  biological  opinion  had  come  to 
regard  Man  himself  as  a  natural  product  and  was  growing  accus- 
tomed to  look  upon  him  as  a  member  of  a  whole  series  of  beings. 
These  beings  extended  to  the  supra-mundane  spheres,  but  the 
lower  series  also,  plants  and  animals,  partook  of  his  essence  in 
varying  degrees,  their  resemblance  to  him  increasing  with  their 
higher  rank  in  the  scale.  Thus  animals  and  plants,  but  especially 
animals,  helped  Man  to  understand  himself. 


III.    The  Bases  of  the  Aristotelian  Biological  System 

{a)  Classification 
Of  the  biological  researches  of  the  Lyceum  we  have  the  three 
great  Aristotehan  works,  the  Historia  aniinalium,  the  De  partibiis 
animalium,  and  the  De  generatione  animalium,  and  on  plants  the 
Historia  plantarum  and  the  De  causis  plantariirn  of  Theophrastus, 
the  puj^il  and  successor  of  Aristotle,  as  well  as  the  later  and 
imperfect  x)eripatetic  work  De  plantis,  probably  composed  by 
Nicholas  of  Damascus  in  the  first  century  b.c."     There  are  also 

^  E.  H.  F.  Meyer,  Geschichte  der  Botanik,  4  vols.,  Konigsberg,  1854-7. 

2  The  history  of  this  work  is  curious.  The  original  work  on  plants  by  Aristotle 
was  commented  on  by  Nicholas  in  Greek.  This  commentary  was  translated  by 
Hunein  ben  Ishak  into  Syriac,  and  this  translation  was  turned,  by  his  son,  into 
Arabic.  In  its  Arabic  dress  it  was  then  modified  by  Thabit  ben  Curra.  From  the 
Arabic  it  was  twice  translated  into  Latin  in  the  thirteenth  century,  on  one  occasion 
by  the  shadowy  and  elusive  Alfredus  Anglicus.  An  authoritative  edition  of  the 
Latin  text  of  Alfredus  was  published  by  E.  H.  F.  Meyer,  Nicola i  Damasceni  de 
plantis  libri  duo  Aristoteli  vulgo  adscripti,  Leipzig,  1841.  See  especially  F.  Wiisten- 
feld,  Die  U eberseizungen  arabischer  Werke  in  das  Lateinische  seit  dem  XI.  Jahr- 
hunderl,  Gottingen,  1877. 


U  (illKKK    lilOJAHJV    AND    ITS   RELATION   TO 

two  Aristotelian  works  on  I  lie  inovcinciits  ol  animals  with  which 
we  arc  not  here  conccrnt'd,  nor  shall  w(^  take;  into  consideration 
such  |)<)inls  in  Aristotle's  works  as  deal  with  the  structun^  of 
man,  since  these  are  Ix'st  reserved  for  se])arate  treatment.  The 
Aristotelian  and  zooloLrical  writings  may  be  considered  first. 

Whatever  be  concluded  as  to  otluu'  works  of  Aristotle,  it  is 
])robably  true  that  any  biologist  wlio  examines  his  zoological 
\vritings  will  accept  what  is  known  as  tlu^  '  note-book  theory  '. 
The  ill  arrangement  of  nuich  of  the  material  and  the  gravity  of 
some  of  the  errors  make  it  difficult  to  conceive  tliat  these  works 
are  in  the  state  designed  for  publication  by  the  master,  with  his 
irenius  for  classification  and  undeniable  powers  of  observation. 
The  only  explanation  that  will  satisfy  is  that  the  more  serious 
blunders  are  the  inistakes  of  the  student  note-taker  who  had  in 
his  hands  the  rough-note  books  of  the  teacher.  It  is  therefore 
probably  true  that  if  Aristotle's  best  biological  observations  are 
taken  as  samples  of  his  scientific  work  we  shall  obtain  the  truest 
picture  of  what  he  himself  was  accustomed  to  teach. 

There  can  be  no  doubt  that  through  much  of  the  Aristotehan 
A\Titing  there  breathes  a  belief  in  a  kinetic  as  distinct  from  a  static 
view  of  existence.  It  is  this  aspect  of  his  teaching  which  brings 
all  hving  things  into  relation  with  man.  In  Aristotle's  study  of 
animal  forms  there  are  two  departments  where  this  kinetic  view 
gains  specially  clear  expression.  These  departments  are  respec- 
tively the  Arrangement  or  Classification  of  Animals,  and  their 
Development,  or,  as  we  now  call  it,  their  Embryology. 

It  is  now  customary  to  summarize  our  knowledge  of  Uving 
beings  in  tabular  form.  As  interpreted  by  a  modern  biologist 
these  classificatory  tables  represent  certain  degrees  of  relationship. 
Modern  systems  of  classification  are  not,  however,  as  is  often 
thought,  closely  comparable  to  genealogical  trees,  because  two 
species  may  be  very  nearly  allied  and  therefore  close  together  in 
the  table  of  classification,  although  they  parted  company  far 
back  in  their  history,  or  again  historically  allied  species  may 
become  widely  differentiated  in  comparatively  few  generations. 
Classificatory  tables  are  rather  intended  to  summarize  structural 
similarities  and  structural  differences,  though,  as  a  rule,  the 
naturahsts  who  draw  them  up  have  no  exact  quantitative  con- 
ception of  the  amounts  of  differences  sigrfified  by  the  degree  of 
separation  in  their  tables.  Indeed  this  absence  of  a  quantitative 
factor  is  among  the  weakest  points  of  modern  biology,  and  it  is 


THE  RISE   OF  MODERN  BIOLOGY  15 

only  in  very  recent  times  that  effective  attempts  have  been  made 
to  remedy  it. 

Now  despite  the  fact  that  no  classificatory  table  of  Aristotle 
has  come  down  to  us,  there  can  yet  be  no  doubt  that  he  formed 
general  ideas  of  a  classification  based  on  the  consideration  of  the 
structure  and  habits  of  animals.  He  uses  the  terms  of  classification 
and  speaks  of  larger  and  smaller  groups  of  animals  which  bear 
greater  or  less  similarity  to  each  other.  It  is  thus  in  accordance 
with  his  meaning  and  is  perhaps  reproducing  his  method  of 
teaching  if  we  draw  up  a  classification  of  animals  from  his  works. 

The  primary  basis  of  his  classification  would  surely  have  been 
the  method  of  reproduction,  a  subject  to  which  he  paid  a  vast 
amount  of  attention  (cf.  Table  on  p.  16).  It  is  therefore  necessary 
to  examine  some  of  his  ideas  on  this  subject. 

He  knew  nothing  of  the  mammalian  ovum,  and  he  regarded  the 
mammalian  embryo  as  a  thing  living  from  the  first,  and  hving  in 
a  higher  sense  than  an  egg  can  be  said  to  live.  The  mammalia 
were  thus  for  him  viviparous  internally  and  not  merely  exter- 
nally in  the  sense  in  which  the  word  viviparous  is  now  used.  The 
remaining  enaima,  sanguineous  animals  or  '  vertebrates '  as  we  now 
call  them,  w^re  primarily  oviparous,  though  some  among  them 
were  viviparous  in  the  external  sense ;  that  is  to  say,  while  the 
young  in  these  cases  were  held  to  develop  always  from  an  egg, 
that  egg  might  sometimes  be  hatched  within  the  mother's  body. 
The  'invertebrates',  or  anaima  in  Aristotle's  notation,  had  on  the 
other  hand  their  own  special  methods  of  reproduction,  among 
which  the  so-called  spontaneous  generation  played  an  important 
part. 

In  considering  the  table  of  classification  that  we  have  drawn 
up  from  Aristotle's  works  and  in  comparing  it  with  any  modern 
system,  the  difficulties  under  which  he  was  working  must  be 
recalled.  He  makes  no  attempt  to  produce  a  complete  system, 
and  he  deals  almost  entirely  with  local  forms.  He  exhibits 
knowledge  of  about  540  species  of  animals.  When  we  consider 
that  of  insect  species  alone  some  half  million  are  now  recognized, 
a  thousand  times  as  many  as  his  total  fauna,  we  shall  be  more 
disposed  to  wonder  that  he  has  fastened  upon  so  many  points  still 
regarded  as  of  classificatory  value,  than  to  criticize  his  errors  or 
the  gaps  in  his  knowledge. 


16 


(;ki<:kk  liioLociV  and  ns  delation  to 


\'ivipai*()UH  (in  tlu- 
internal  sense) 


MNAIMA.    (Siiii^Miiiuous  and  either  viviparous  or  ovi parous) = Vertebrates. 

1.  Man. 

2.  Cetacea. 
:\.   \'iv'ij)aroii.s  Quadrupeds  : 

{(i)  Xon-ampliodonta  (Kuminants  with  cloven 

hoots  and  incisors  in  lower  jaw  only). 
(/>)  Monycha  (with  single  hoofs), 
(c)  Otiier  viviparous  quadrupeds, 
r  4.  Birds  : 

(a)  Gampsonycha  (Rapt ores  with  talons), 
{!>)  Steganopodes    (Natatores    witli    webbed 

feet), 
(r)   Peristeroeide  (Columbidae). 
{(l)  Apodes  (Swifts,  martins,  swallows), 
(e)  Other  birds. 

5.  Oviparous    Quadrupeds    (Anipiiibia    and    most 
Reptiles). 

6.  Ophiode  (Serpents). 
„..^,        ri.  Fishes  : 

.  (    J  («)  Bony  fish. 

imperfect-^  (6)  Selachia  (Cartilaginous  fish  and  Fishing- 

ovum      (^  fj.og) 

AXALMA  (Non-sanguineous  and  either  oviparous,  vermiparous  or  budding) 

= Invertebrates. 


Oviparous 

(though 

sometimes 

externaUij 

viviparous^ 


With 
perfect    •< 


ovum 


j  1.  Malacia  (Cephalopods) 

1  2.  K  ~ 


Witli  imperfect  ovum  .  .  |  ^,  Malacostraca  (Crustacea). 

With  scolex         .  .  .3.  Entoma  (Insects,  spiders,  scorpions,  &c.). 

With  generative  slime,  buds,  I  4.  Ostracoderma  (Molluscs  except  Cephalo- 

or  spontaneous  generation  *  pods,  Echinoderms,  &c.). 

With  spontaneous  generation  |  .  z^^p^yta  (Sponges,  Coelenterates,  &c.). 

Aristotle's  primary  division  into  Enaima  and  Anaima,  or  as  we 
call  them  Vertebrates  and  Invertebrates,  is  one  still  universallj' 
accepted.  The  two  groups  are  now,  it  is  true,  regarded  as  incom- 
mensurate in  evolutionary  value,  but  this  has  only  been  recognized 
during  the  last  gejieration  or  two,  and  the  division  survives  as 
an  effective  dichotomy  of  our  knowledge.  When  we  examine  his 
Enaima  we  see  a  division  into  groups  which,  with  the  forms  known 
to  him,  could  hardly  be  improved.  The  fish-Hke  Cetacea  are 
separated  too  widely^  from  the  other  mammals,  but  Aristotle 
nevertheless  knows  of  their  mammaUan  character  and  recalls 
tlie  fact  that  they  suckle  their  young.  He  is  in  no  danger  of 
confusing  them  with  fish.  '  All  animals  ',  he  says,  '  that  are  in- 
ternally and  externally  viviparous  have  breasts,  as  for  instance  all 
animals  that  have  hair,  as  man  and  the  horse,  and  the  cetaceans, 
as  the  dolphin,  the  porpoise,  and  the  whale,  for  these  animals  have 
breasts  and  are  supplied  with  milk.     Animals  that  are  oviparous 


Pi.ATi:  \'III.     Lcyden    MS.    V'oss    I.dt.    (J.  9   Apiilcius    X'ltli    cnt. 

a v:u(no\ <*^c  IX(   \i\\ \T4>sp< I'. m » •  |^ • 


!s/VvrheRTi\ 


f^rv\<:;A 


83  r    /■' j-r,  gn  --  B  1  a  c  k  b  c  r  ry 


.heT?iV.v-((^  'fV^xSibWl 


THE   RISE   OF  MODERN   BIOLOGY  17 

or  only  externally  viviparous  have  neither  breasts  nor  milk,  as 
the  fishes  and  the  bird.'  ^ 

Tlie  passages  in  which  Aristotle  describes  the  Cetaceans  are 
worth  putting  together  as  giving  a  general  idea  of  his  powers  of 
zoological  classification,  and  they  provide  an  excellent  illustration 
of  the  stage  that  he  had  reached  in  the  study  of  comparative 
anatomy  and  physiology. 

'  Some  animals  are  viviparous,  others  oviparous,  others  vermi- 
parous.  Among  the  viviparous  are  man,  the  horse,  the  seal,  and 
all  other  animals  that  are  hair-coated,  and,  of  marine  animals, 
the  cetaceans,  as  the  dolphin  and  the  so-called  Selachia."  .  .  . 
The  dolphin,  the  whale,  and  all  the  rest  of  the  Cetacea,  all,  that 
is  to  say,  that  are  provided  with  a  blow-hole  instead  of  gills,  are 
[internally]  viviparous.  That  is  to  say,  no  one  of  all  these  is 
ever  seen  to  be  supplied  with  eggs,  but  directly  with  an  embryo 
from  whose  differentiation  the  animal  develops,  just  as  in  the 
case  of  mankind  and  the  viviparous  quadrupeds.^ .  .  .  All  creatures 
that  have  a  blow-hole  respire  and  inspire,  for  they  are  provided 
with  lungs.  The  dolphin  has  been  seen  asleep  with  his  nose 
above  water,  and  when  asleep  he  snores.*  .  .  .  One  can  hardly 
allow  that  such  an  animal  is  terrestrial  and  terrestrial  only,  or 
aquatic  and  aquatic  only,  if  by  terrestrial  we  mean  an  animal 
that  inhales  air,  and  if  by  aquatic  we  mean  an  animal  that  takes 
in  water.  For  the  fact  is  the  dolphin  performs  both  these  pro- 
cesses :  he  takes  in  water  and  discharges  it  by  his  blow-hole,  and 
he  also  inhales  air  into  his  lungs  ;  for  the  creature  is  furnished 
with  these  organs  and  respires  thereby,  and  accordingly,  when 
caught  in  the  nets,  he  is  quickly  suffocated  for  lack  of  air.  He 
can  also  live  for  a  considerable  while  out  of  the  water,  but  all 
this  while  he  keeps  up  a  dull  moaning  sound  corresponding  to 
the  noise  made  by  air-breathing  animals  in  general ;  furthermore, 
when  sleeping,  the  animal  keeps  his  nose  above  water,  and  he 
does  so  that  he  may  breathe  the  air.  .  .  .  For  the  fact  is,  some 
aquatic  animals  [as  fish]  take  in  water  and  discharge  it  again, 
for  the  same  reason  that  leads  air-breathing  animals  to  inhale 
air  ;  in  other  words,  with  the  object  of  cooling  the  blood.  Others 
[as  cetaceans]  take  in  w^ater  as  incidental  to  their  mode  of  feeding  ; 
for  as  they  get  their  food  in  the  water  they  cannot  but  take  in 
water  along  with  their  food.'  ^ 

'  The  dolphin  bears  one  at  a  time  generally,  but  occasionally 
two.  The  whale  bears  one  or  at  the  most  two,  generally  two. 
The  porpoise  in  this  respect  resembles  the  dolphin.  .  .  .  The 
dolphin  and   the   porpoise   are  provided   with   milk,   and   suckle 

^  Historia  animalium,  iii.  20  ;   52P21.        -  Historia  animalium,  i.  5  ;   489*34. 
•^  Historia  animalium,  vi.  12  ;   566"  2.  "^  Historia  animalium,  vi.  12  ;   566"  12. 

^  Historia  animalium,  viii.  2  :   589^  31. 

2391 


18 


(}Rh:KK    l5l()].()(iY    AND    ITS    liKJ.ATION   TO 


tlicir  yoimjj;.  They  also  talvc  tlicir  yoiuig,  wJit'ii  siuall,  insider 
them.  Tlic  yoimji;  of  the  dolpliiii  grows  rapidly,  l)ei)ig  full-growji 
at  tiMi  ycais  of  age.  Its  pc-riod  of  gestation  is  ten  inonth.s.  Jt 
brings  forth  its  young  in  sununcr,  and  never  at  any  otlier  season. 
Its  young  acc()ni|)}iny  it  for  a  considerable  period  ;  and,  in  fact, 
the  creature  is  reinaika,l)le  for  tlie  strengtli  of  its  ])arental  affection.'' 

The  Ili.slorid  (tit i nidi liiin  in  wliieli  tliese  ])assages  occur  became^ 
accessible  in  versions  l)y  Michael  Scot  (1175  '.''-1204  ?),"''  })y  Albertus 


LaftinUurcdcl'Oudre.^ucUs  Lalinnio.inntnt  Orcajit 
Orcynum. 


Fig.  1.  GRAMPUS  AND  NEWLY-BORN  YOUNG 

The  foetus  is  still  surrounded  by  its  membranes  and  the  after-birth  is  in  process  of  extrusion. 

From  Pierre  Belon,  Hisloire  nalurelle  de.^  estranges  poisson-s  marins,  avec  la  vraie  peincture  el 

description  du  daidphin  et  de  plusieurs  autres  de  son  espece,  Paris,  1551. 

Magnus  (1206-80),^  and  perhaps  by  William  of  Moerbeke  (died 
c.  1281).  The  work  was  again  rendered  into  Latin  by  Theodore 
Gaza,  about  1450.^  Yet  the  mammalian  affinities  of  the  Cetacea 
appear  to  have  been  generally  overlooked  in  the  Middle  Ages 
and  at  the  Revival  of  Learning  until  Pierre  Belon  (1507-64) 
repeated  Aristotle's  observations  in  the  middle  of  the  sixteenth 
century   and   published  a  description  of  the   cetacean   placenta 

^  Hisioria  animalium,  vi.  12  ;   566''  7. 

2  Translated  from  the  Arabic.  Cf.  F.  Wiistenfeld,  loc.  cit.,  p.  101.  Roger 
Bacon  teUs  us  that  in  1230  '  Michael  Scot  appeared  [at  Oxford]  bringing  with 
him  the  works  of  Aristotle  on  natural  history  and  mathematics,  y>iih.  wise  exposi- 
tors, so  that  the  philosophy  of  Aristotle  was  magnified  among  the  Latins  '.  It 
appears  that  Scot  produced  two  versions  of  the  De  AnimalibiLS,  one  entitled  De 
Animalibus  ad  Caesarem  and  the  other  Tractatus  Avicennae  de  Aninuilibus.  He 
also  incorporated  ideas  from  the  De  Generatione  Animalium  in  his  lAber  de  secretis 
naturae. 

"  An  edition  of  Albert's  commentary  has  been  produced  by  H.  Stadler,  Albertus 
Magnus  de  animalibus  libri  XXVI  nach  der  Coiner  Urschrift,  Munster  i.  W.,  1916 
and  1921,  in  Baeumke's '  Beitrage  zur  Geschichte  der  Philosophic  des  Mittelalters.' 

*  First  printed  Venice,  1476. 


THE   RISE  OF  MODERN  BIOLOGY 


19 


La]^einilure(Ul'EmbryoK  £w  Marfouitt. 


(Figs.  I  and  2).  Belon  is  further  worthy  of  commemoration  as  he 
was  perhaps  the  first  among  the  moderns  to  make  an  attempt 
at  a  comparative  anatomy,  for  in  one  of  iiis  works  he  sets  forth  the 
homologues  of  the  vertebrate  skeleton  along  somewhat  similar  lines 
to  those  of  Aristotle^  (Fig.  3),  a  conception  soon  developed  by 
Coiter  well  beyond  the  Aristotelian  level." 

The  classification  of  birds  is  to  this  day  in  an  unstable  state.  We 
may  say  that  Aristotle's  grouping  is 
substantially  that  which  prevailed  in 
scientific  works  till  recent  times  and 
still  remains  as  the  popular  division. 
His  separation  of  the  cartilaginous 
from  the  bony  fishes,  on  the  other 
hand,  still  stands  in  scientific  works, 
and  is  a  stroke  of  genius  which  must 
have  been  reached  by  means  of  careful 
dissection.  It  is  marred  only  by  the 
inclusion  of  one  peculiar  bony  form, 
the  fishing-frog,  or  Lophius,  among 
the  cartilaginous  fishes,  and  investi- 
gation shows  that  the  skeleton  of 
this  creature  is,  in  fact,  pecuUarly 
cartilaginous.  Aristotle  himself  re- 
garded the  Lophius  as  aberrant 
among  cartilaginous  fishes. 

For  the  Anaima  or  Invertebrates 
even  modern  systems  of  classification 
are  but  tentative.  There  is  an  enor- 
mous number  of  species,  and  after 
centuries  of  research  naturalists  still 
find  vast  gaps  even  in  the  field  of  mere  naked-eye  observation. 
Nevertheless,  with  the  instinct  of  genius,  and  with  only  some  240 
of  these  forms  on  which  to  work,  Aristotle  has  fastened  on  som^e  of 
the  most  salient  points.  Especially  brilliant  is  his  treatment  of  the 
Molluscs.  There  can  be  no  doubt  that  he  dissected  the  bodies  and 
carefully  watched  the  habits  of  octopuses  and  squids,  2Ialacia  as 
he  calls  them.      He  separates  them  too  far  from  the  other  Molluscs, 

^  The  suggestion  had  aheady  been  made,  though  in  a  less  complete  form,  by 
Vesalius  in  the  De  fabrica  corporis  huniani,  1543.  There  are  also  traces  of  the 
conception  of  a  comparative  anatomy  in  the  MSS.  of  Leonardo  da  Vinci. 

^  Volcher  Coiter,  Lectiones  Gabrielis  Fallopii  de  parlihus  similaribas  humani 
corporis  ex  flicersis  cxemplaribus,  Nuremberg,  1575. 


Fig.  2.  THE  UTERUS  OP  THE 
PORPOISE 
Opened  to  show  foetus  attached  by 
umbilical  cord  to  placenta.  From 
Pierre  Belon,  Histoire  naturdle  des 
estranges  poissons  mar  ins,  avec  la  vraie 
peincture  et  description  du  daulphin  et 
de  plusieurs  autres  de  son  espece,  Paris, 
1551. 


20 


(jiu<:kk  iii()L()(;v  and  its  i^klatiox  to 


groujK'd  by  liim  us  (J.sh(((od<'rnia,  \nii  liis  actual  cicscri ptious  of  Die 
.struct lire  of  the  ('cplialoixxls  arc  exceedingly  remarkable.  (Cf, 
p.  Ii!>  11.)      His  distinction  between  the  M (ddcoalracu  or  Crustacea, 


uc  let  vniroicot   de  pctici 
U9p  grudif auuci  aojrcanem:! 


Fig 


THE     SKELETON     OF     A     MAX    AND     OF 
A     BIRD     C  O  M  P  A  R  E  D 
From  Pierre  Belon,  Lhisloire  de  la  nature  des  oyseaux,  Paris,  1555. 

Entoma,  Sponges,  and  Jellyfisli  are  also  still  of  value,  and  these 
divisions  remain  along  much  the  same  lines  as  he  left  them. 

{h)  Phylogeny 
Aristotle  no\\'here  formally  exhibits  either  a  '  Scala  Naturae  ' 
or  a  '  genealogical  tree  ',  devices  in  which  naturalists  have  de- 
lighted for  the  last  two  centuries,  but  he  constantly  comes  so 
near  to  such  conceptions  that  there  is  no  great  difficulty  in  re- 
constructing his  scale  from  his  descriptions  (Fig.  4). 

'  Nature  ',  he  says,  '  proceeds  little  by  little  from  things  lifeless 
to  animal  life  in  such  a  way  that  it  is  impossible  to  determine  the 
exact  line  of  demarcation,  nor  on  which  side  thereof  an  inter- 
mediate form  should  lie.  Thus,  next  after  lifeless  things  in  the 
upward  scale  comes  the  plant,  and  of  plants  one  will  differ  from 
another  as  to  its  amount  of  apj^arent  vitality  ;  and,  in  a  word, 
the  whole  genus  of  plants,  whilst  it  is  devoid  of  life  as  compared 


THE  RISE  OF  :\[ODEPvN   BIOLOGY 


21 


with  an  animal,  is  endowed  with  hfe  as  com])ared  with  other  cor- 
poreal entities.  Indeed,  there  is  observed  in  jjlants  a  continuous 
scale  of  ascent  towards  the  animal.  So,  in  the  sea,  there  are  certain 
objects  concerning  which  one  would  be  at  a  loss  to  determine 
whether  they  be  animal  or  vegetable.  For  instance,  certain  of  these 
objects  are  fairly  rooted,  and  in  several  cases  perish  if  detached.'  * 


MAK 

OTHER  VMEARA 

=  Mammalia 

mMk 

=  P.eptiles.  Birdjs,  AiripKllia  and  FlsIi 

IMLACIA 

=  Cetiialapocls 

MALACOSTRACA 

=  Crustacea 

ENTOlvIA 

"  Otlier  ArtKropocis 

__^ — ' 

05TRAC0DER1M 

■--..^Mier  Mollxiscs 

"^"^^        ^               TETHYA  ^~^~ 

^A^cidians  etc 

ACALEPHAE     %^          HOLOTHOIMA 

=  Holot}iunaTis?''etc. 

-___^ 

^         SPONGIM^ 

=  Sponge- 

Jelly  Fi^l.^ 


'^   '\   LOWER  PLANTS /'    ^ 

Fig.  4.     The  order  of  living  things,  put  together  from  the  desciiptions  of  Aristotle, 

'  A  sponge,  in  these  respects  completely  resembles  a  plant,  in 
that  throughout  its  life  it  is  attached  to  a  rock,  and  that  when 
separated  from  this  it  dies.  Slightly  different  from  the  sponges 
are  the  so-called  Holothourias  and  the  sea-lungs,  as  also  sundry 
other  sea-animals  that  resemble  them.  For  these  are  free  and 
unattached,  yet  they  have  no  feeling,  and  their  life  is  simply 
that  of  a  plant  separated  from  the  ground.  For  even  among  land- 
])lants  there  are  some  that  are  independent  of  the  soil  ...  or  even 
entirely  free.  Such,  for  example,  is  the  ])lant  which  is  found  on 
Parnassus,  and  which  some  call  the  Epipetrum.  This  you  may  hang 
up  on  a  peg  and  it  will  yet  live  for  a  considerable  time.  Sometimes 
it  is  a  matter  of  doubt  whether  a  given  organism  should  be  classed 
with  plants  or  with  animals.  The  Tethj'^a,  for  instance,  and  the  like 
so  far  resemble  plants  as  they  never  live  free  and  unattached,  but, 
on  the  other  hand,  inasmuch  as  they  have  a  certain  Hesh-like  sub- 
stance, they  must  be  supposed  to  possess  some  degree  of  sensibility.' 


'  Historia  animalium,  viii.  1  ;   58H'J  4. 
-  De  partihiis  animalium,  iv.  5  ;  GSi-*  15. 


22  (iKKKlv    lil()J.(K;^    AND   JT.S   llELATION    TO 

'  Tlic  Acjilcpluic  or  S(!a-iU'ttl(',s,  as  tlicy  Jtrt'  variously  called,  .  .  . 
lie  outside  (lie  reco^uized  <^rou|)s.  Tlnnr  coiistit  ution,  like  tliat 
of  the  'relhya,  a])|)r()xiniates  thcni  on  tlio  one  side  to  plants,  on 
tlie  otlier  side  to  animals.  For  seeing  that  some  of  them  can 
detaeii  themselves  and  vnw  fasten  on  their  food,  ajid  that  they 
are  sensible  of  objects  which  come  in  contact  with  them,  they 
nnist  be  considered  to  have  au  animal  nature.  Tlie  like  conclusion 
follows  fro!H  their  using  the  asj)crity  of  thcii'  bodies  as  a  protection 
against  their  enemies.  But,  on  the  otlicj-  hand,  they  are  closely 
allied  to  plants,  firstly  by  the  imperfection  of  their  structures, 
secondly  by  their  being  al)le  to  attach  themselves  to  the  rocks, 
which  they  do  with  great  rapidity,  and  lastly  by  their  Jiaving  no 
visible  residuum  notwithstanding  that  they  possess  a  mouth.'  ' 

Thus  '  Nature  yjasses  from  lifeless  objects  to  animals  in  such 
unbroken  sequence,  interposing  between  them  beings  which  live 
and  yet  are  not  animals,  that  scarcely  any  difference  seems  to  exist 
between  two  neighbouring  grou2)s  owing  to  their  close  2)roximit3\' " 

'  ]n  regard  to  sensibility,  some  animals  give  no  indication 
whatsoever  of  it,  whilst  others  indicate  it  but  indistinctly.  Further, 
the  substance  of  some  of  these  intermediate  creatures  is  flesh-like, 
as  is  the  case  with  the  so-calle^l  Tethya  (ascidians)  and  the 
Acalephae  (or  sea  anemones  ?)  ;  but  the  sponge  is  in  every  resi)ect 
like  a  vegetable.  And  so  throughout  the  entire  animal  scale  there 
is  a  graduated  differentiation  i]i  amount  of  vitality  and  in  capacity 
for  motion.  A  similar  statement  holds  good  with  regard  to  habits 
of  life.  Thus,  of  plants  that  spring  from  seed,  the  one  function 
seems  to  be  the  reproduction  of  their  own  particular  species,  and 
the  sphere  of  action  with  certain  animals  is  similarly  limited. 
The  faculty  of  reproduction,  then,  is  common  to  all  alike.  If 
sensibility  be  superadded,  then  their  lives  will  differ  from  one 
another  in  respect  to  sexual  intercourse  and  also  in  regard  to 
modes  of  parturition  and  ways  of  rearing  their  young.  iSome 
animals,  like  plants,  simply  procreate  their  own  species  at  definite 
seasons  ;  other  animals  busy  themselves  also  in  procuring  food 
for  their  young,  and  after  they  arc  reared  quit  them  and  have  no 
further  dealings  with  them  ;  other  animals  are  more  inteUigent 
and  endowed  w ith  memory,  and  they  live  with  their  offspring  for 
a  longer  period  and  on  a  more  social  footing.'  "^ 

(c)  07itogeny 

So  much  for  Aristotle's  treatment  of  the  kinds  of  hving  things. 

Evolutionary  doctrine  is  also  foreshadowed  bj^  him  in  his  theories 

of  the   development   of  the  individual.      This  fact  is   obscured, 

however,  by  his  peculiar  view  of  the  nature  of  i)rocreation.     On 

^  De  partibus  animalium,  iv.  5  ;  68P  36. 
-  De  partibus  animalium,  iv.  5  ;  681*  10. 
^  Historia  animalium,  viii.  1  ;  588"  16, 


THE  RISE  OF  MODERN   BIOLOGY  23 

this  topic  his  general  conclusion  is  that  the  material  substance  of 
the  embryo  is  contributed  by  the  female,  but  that  this  is  mere 
passive  formable  material,  almost  as  though  it  were  the  soil  in 
which  the  embryo  grows.  The  male  contributes  the  essential 
generative  agency,  but  it  is  not  theoretically  necessary  for  any- 
thing material  to  pass  from  male  to  female.  The  material  that 
does  in  fact  pass  with  the  seed  of  the  male  is  an  accident,  not  an 
essential,  for  his  essential  contribution  is  not  matter  but  form  and 
principle.  Aristotle,  it  appears,  was  prepared  to  accept  instances 
of  fertilization  without  material  contact. 

'  The  female  does  not  contribute  semen  to  generation  but 
does  contribute  something  .  .  .  for  there  must  needs  be  that  which 
generates  and  that  from  which  it  generates.  ...  If,  then,  the  male 
stands  for  the  effective  and  active,  and  the  female  considered  as 
female,  for  the  passive,  it  follows  that  what  the  female  would 
contribute  to  the  semen  of  the  male  would  not  be  semen  but 
material  for  the  semen  to  work  upon.  .  .  .  Now  how  is  it  that  .the 
male  contributes  to  generation,  and  how  is  it  that  the  semen  from 
the  male  is  the  cause  of  the  offspring  ?  Does  it  exist  in  the  body 
of  the  embryo  as  a  part  of  it  from  the  first,  mingling  with  the 
material  which  comes  from  the  female  ?  Or  does  the  semen  con- 
tribute nothing  to  the  material  body  of  the  embryo  but  only  to 
the  power  and  movement  in  it  ?  For  this  power  is  that  which  acts 
and  makes,  while  that  which  is  made  and  receives  the  form  is  the 
residue  of  the  secretion  in  the  female.  Now  the  latter  alternative 
appears  to  be  the  right  one  both  a  priori  and  in  view  of  the  facts.'  ^ 

There  was,  however,  another  view  of  generation,  perhaps  of 
Epicurean  origin,  that  was  prevalent  in  antiquity.  According  to 
this  theory  the  foetus  was  a  joint  product  of  male  semen  and  of 
some  analogous  factor  secreted  by  the  female.-  Among  later 
writers,  from  Galen  onward,  the  Aristotelian  and  Epicurean  views 
were  often  blended  and  confused.  After  the  thirteenth  century, 
however,  the  Aristotelian  doctrine  was  that  mainly  held  and  it 
lasted  on  until  quite  modern  times.  \  Thus  it  profoundly  influenced 
William  Harvey  in  the  seventeenth  centuiy.  With  the  discovery 
of  the  spermatozoa,  however,  by  Leeuwenhoek  and  Hamm,  in 
1677,  it  became  substantially  untenable.  The  view  of  Aristotle 
fell  altogether  into  discredit  in  the  nineteenth  century,  during  the 

^  Be  generatione  animalium,  i.  21  ;  729^21. 

2  The  theory  is  succinctly  stated  by  Lucretius,  iv,  11.  1229-31  : 
Semper  enini  partus  duplici  de  semine  constat, 
atque  utri  similest  magis  id  quodcumque  creatur, 
eius  habet  plus  parte  aequa. 


24  GRKKK    BIOLOCJV   AND    ITS   liKLATlON    JO 

loii^  period  ot  what  may  be  (lallcd  histoloj^ifal  (loniinatioii.  We 
havr  now,  howcv ci',  ciitcicd  on  a  new  cxpciiniciital  period  in 
biology,  and  icccnt  work  on  nicclianical  stinndus  of  1  lir  ovnni  lias 
donionst  rated  that  it  is  indeed  possible  Tor  devclopnK'iit  to  proceed 
witiioiit   passai^e  ol  material  tiom  the  male. 

Aristotle's  most  important  endjryolo^ieal  i-esearches  were  made 
upon  tlie  eliick.  He  says  that  the  first  signs  of  dcvelo])jnent  are 
noticeable  after  three  days,  the  lieart  being  visible  as  a  pal|)itating 
blood  sjK)t  whence,  as  it  develops,  two  meandering  blood-vessels 
extend  to  the  surrounding  tunics. 

'  Generation  from  the  egg  ',  he  says,  '  ])roceeds  in  an  identical 
maimer  with  all  birds,  but  the  full  periods  from  conception  to 
birth  differ.  With  the  common  hen  after  three  days  and  nights 
there  is  the  first  indication  of  the  embryo.  .  ,  .  The  heart  apy)ears 
like  a  speck  of  blood,  in  the  white  of  the  egg.  This  ])oint  beats 
and  moves  as  though  endowed  with  life,  and  from  it  two  vein- 
ducts  with  blood  in  them  trend  in  a  convoluted  course  .  .  .  and 
a  membrane  carrying  bloody  fibres  now  enveloyjs  the  yolk,  leading 
off  from  the  vein-ducts.'  ^ 

A  httle  later  he  observed  that  the  body  had  become  distin- 
guishable, and  was  at  first  very  small  and  white. 

'  The  head  is  clearly  distinguished  and  in  it  the  eyes,  swollen 
out  to  a  great  extent.  This  condition  of  the  eyes  lasts  on  for 
a  good  while,  as  it  is  only  by  degrees  that  they  diminish  in  size 
and  collapse.  At  the  outset  the  under  portion  of  the  body  appears 
insignificant  in  comparison  with  the  upper  portion.  Of  the  two 
ducts  that  lead  from  the  lieart,  the  one  proceeds  towards  the 
circumjacent  integument,  and  the  other,  like  a  navel-string, 
towards  the  yolk.  .  .  . 

'  When  an  egg  is  ten  days  old  the  chick  and  all  its  parts  are 
distinctly  visible.  The  head  is  still  larger  than  the  rest  of  the 
body  and  the  eyes  larger  than  the  head.  At  tliis  time  also  the 
larger  internal  organs  are  visible,  as  also  the  stomach  and  the 
arrangement  of  the  viscera  ;  and  the  veins  that  seem  to  proceed 
from  the  heart  are  now  close  to  the  navel.  From  the  navel  there 
stretch  a  pair  of  veins,  one  towards  the  membrane  that  envelops 
the  yolk  and  the  other  tow^ards  that  membrane  which  envelops 
collectively  the  membrane  wlierein  the  chick  lies,  the  membrane 
of  the  yolk,  and  the  intervening  liquid.  .  .  .  About  the  twentieth 
daj^  if  j'-ou  open  the  egg  and  touch  the  chick,  it  moves  inside 
and  chirps  ;  and  it  is  already  coming  to  be  covered  with  down, 
when,  after  the  twentieth  dav  is  past,  the  chick  begins  to  break 
the  shell.'  - 

1  Historia  animal ium,yi.  3;  501" 4.  -  Historia  animalium,  vi.3  ;  561''  18. 


THE   RT8E  OF  MODERN   BJOLOGIY 


2n 


To  realize  what  must  have  been  Aristotle's  impressions  on 
seeing  the  developing  chick  we  should  not  only  eliminate  our  own 
embryological  prepossessions  but  should  also  divest  ourselves  of 
such  modern  conveniences  of  a  laboratory  as  incubator,  water- 
bath,  and  microscope,  and  even  lens.  For  our  purpose  of 
comparison,  better  than  the  description  of  a  modern  text-book 
of  embryology  is  the  account  of  such  a  pioneer  embryologist  as 
Fabricius  ab  Aquapendente  (1537-1619)  whose  work  was  dime 
before   the   microscope  had  come  into  use  (Fig.    5).      Fabricius 


Fig.  5.     THE     YOUX(;     CHICK 
From  Fabricius  ab  Aquajjendente's  De  formatione  ovi  ct  pulli,  Padua,  1604. 

was  not,  it  is  true,  the  first  of  modern  Avriters  to  make  embryo- 
logical  observations ;  for  that  position  Leonardo  da  Vinci  is 
perhaps  the  most  likely  candidate.  Rieff  (1500-58)  also,  in  a  work 
for  mid  wives  (1554),  had  written  matter  concerning  the  develop- 
ment of  the  human  embryo  that  was  not  without  point.^  ^loreover, 
Goiter  (1534-1590)  had  already  (1573)  discussed  the  incubated 
fowl's  egg-  in  a  maimer  that  displayed  an  understanding  of  the 
nature  of  the  vitelline  duct  to  which  neither  Fabricius  nor  even 

^  Jacob  Rieff,  Trostbilchle,  Zurich,  1554.  There  is  a  Latin  edition  of  this 
work  (tran.slated  by  Wolfgang  Haller  ''.),  De  conceptu  et  generatione  Iwynlnis, 
Zurich,  1554,  and  an  excellent  anonymous  English  translation,  The  Expert  Mid- 
wife, London,  1637. 

-  Volcher  C'oiter.  Externarum  et  inteniaruin  principnlinm  humnni  corporis 
partium  tabulae,  atque  anatomicae  exercitationes  observationrsque  variae  dirersi.>t  ac 
artificiossissimis  figuris  illustratae,  Nuremberg,  1573. 


21)       (;i{1«:ek  biolocn   and  ri\s  ijki.ation  to 

Harvey  altoj^othcr  attained,'  althoupjli  it  had  been  grasped  by 
Aristotle.^  But  Fabrieius  wan  tlie  tir.st  to  imitate  Aristotlo  in 
making  extensive  embryologieal  observatioiiK  under  controlled 
conditions.'' 

Like  Aristotk',  l^'abricius  earried  on  his  researches  witliout 
means  of  magnification;  like  him  he  did  his  work  almost  without 
help  from  previous  observers;  following  Aristotle,  he  held  that 
there  was  a  fundamental  distinction  between  the  male  and  female 
contribution  to  the  formation  of  the  embryo  in  the  case  of  the 
viviparous  placental  animals,  and  as  with  Aristotle,  the  ovum  of 
mammals  was  unknown  to  him,  though  its  existence  was  suspected 
by  his  2:)upil  Harvey.  For  these  pioneers  of  embryology  the  semen 
or  sperm  was  indeed  literally  the  seed,  the  fertilizing  principle — 
the  word  used  for  the  seed  of  animals  was  the  same  as  that  used 
for  plants  both  in  Latin  and  in  Greek — a  seed  which  was  sown  in 
the  soil  of  the  mother's  womb  where  it  was  nourished  and  where 
it  grew.  Harvey  in  his  work  on  Generation  suggested,  without  full 
evidence,  that  '  almost  all  animals,  even  those  which  bring  forth 
their  young  alive  and  man  himself  are  produced  from  eggs  ',^  but 
it  was  not  until  the  last  quarter  of  the  seventeenth  century  and  the 
appearance  of  the  work  of  de  Graaf  ^  (Figs.  6  and  7),  Swammerdam,*^ 
and  Stensen "  that  the  notion  came  clearty  into  view  that  the  so- 

^  111  modern  times  the  nature  of  the  vitelline  duct  was  first  described  by 
Goiter,  but  his  work  was  overlooked  until  his  observations  were  repeated  by  Stensen 
in  his  De  musculis  et  glandulis  observation iim  specimen,  Copenhagen,  1664. 

"  Aristotle,  Historia  animalium,  vi.  3. 

^  Hieronymus  Fabricius  ab  Aquapendente,  De  formatione  ovi  et  pulli,  Padua, 
1604. 

'^  The  phrase  omne  vivum  ex  ovo,  sometimes  attributed  to  Harvey,  cannot, 
however,  actually  be  found  in  his  writings. 

■^  Regnier  de  Graaf,  De  mulierum  organis  generationi  inservientibus  tractatus 
novus,  demonstrans  tarn  homines  et  animalia,  caetera  omnia,  quae  vivipara  dicuntur, 
haud  minus  quam  ovipara,  ab  ovo  originem  ducere,  Leyden,  1672. 

**  Jan  Swammerdam,  Miraculum  naturae  sive  uter  muliebris  jabrica,  Leyden, 
1672. 

"  In  1667  Stensen  pubUshed  his  Elementorum  myologiae  specimen  .  .  .  cui 
accedunt  canis  Carchariae  dissectum  caput,  et  dissectus  piscis  ex  canum  genere  at 
Florence,  reprinted  Amsterdam,  1669.  In  the  third  treatise  of  this  work  he 
maintained  that  the  testes  of  women  were  analogous  to  the  ovaria  of  oviparous 
animals  and  ought  to  be  called  by  that  name.  In  1675  he  published  at  Copen- 
hagen in  the  Acta  Hafniensia  his  Observationes  anatomicae  spectantes  ova  viviparo- 
rum,  in  which  he  briefly  described  ova  in  a  variety  of  viviparous  animals.  In 
an  adjacent  publication  of  the  same  year  of  the  Acta  Hafniensia  entitled  Ova 
viviparorum  spectantes  observationes  he  gives  a  diagram  illustrating  the  an  dogy 


I 


THE  RISE   or  MODERN  BIOLOGY 


27 


called  'testes'  of  the  female  really  contained  eggs  or  ova  com- 
parable to  the  ova  of  oviparous  creatures.  In  the  absence  of  this 
Ivuowledge  Aristotle,  like   Fabricius,  was  unable  to  set  forth  an 


Fig.  6.  From  Regnier  de  Graaf's  De  mulierum  organis  generationi  inservientibus,  Leyden, 
1672.  To  the  left  is  the  '  testicle  or  ovary',  as  he  calls  it,  of  a  woman.  It  is  cut  open  along 
the  line  a  ;  bb  are  '  ova  '  of  various  sizes  contained  in  the  substance  of  the  '  testis  ' ; 
c  c  are  blood  vessels ;  d  is  the  ligament  of  the  ovary  ;  E  a  part  of  the  Fallopian  tube 
and  G  its  opening  ;  h  and  i  are  the  ornamenta  foliacea  tubarum.  To  the  right  is  the 
ovary  of  a  cow  similarly  cut  open  along  the  line  aa  ;  bb  is  the  Glandulosa  substantia, 
quae  post  ovi  expulsionem  in  testibus  reperitur,  or  as  we  call  it  the  corpus  luteum,  cc  being 
the  '  almost  obliterated  cavity  '  in  which  the  ovum  was  once  contained  ;  dd  are  ova  ; 
EE  blood  vessels  ;  r,  g,  h  the  Fallopian  tube.  Between  the  two  larger  figures  is  the  Graafian 
follicle  AB  of  a  sheej),  c  being  the  ovum  removed  from  it. 

explanation   of    the    mechanism   of   generation   that   adequately 
covered  the  phenomena. 


of  the  uteri  of  vipara  and  ovipara.  Thus  Stensen  has  the  priority  in  the  suggestion 
that  the  testes  of  the  female  mammal  produce  ova  but  de  Graaf  has  the  priority 
of  demonstration. 

The  claim  disseminated  by  A.  Portal  in  his  Histoire  de  VAnatomie  et  de  la 
Chirurgie,  6  vols.,  Paris,  1770-1773,  that  JeanMathieu  Ferrari  da  Grado  (fl.  1450) 
was  the  discoverer  of  the  ovarian  nature  of  the  female  testes,  is  effectually  dis- 
posed of  by  da  Grado's  collateral  descendant  H.  M.  Ferrari,  in  his  Une  chaire  de 
Medecine  au  XV  siecle,  Paris,  1899,  p.  115  ff. 


28 


CinOF^K    lil()L()(JV    AND    ITS    IIKLATIOX    TO 


Aristotle,   true  to   tin;  ^ciu'ral   j^radatioiial    view   tliat   he  had 
fonncd  of  Nature,  held  that  the  most  priiniti v(!  and  fiiiKhimciitally 

iiDportaiit    or<^aiis   niak<^  their 
^  appcaiaiicc  before  the  others. 

"^  Among  tli(i  organs  all  give 
|)laee  to  th(^  h(!art,  which  he 
considered  '  th(;  first  to  live 
and  the  hist  to  die  '.^  Here 
again  he  was  followed  by 
the  great  investigators  of  the 
newly  revived  experimental 
method.  Harvey  has  en- 
shrined this  idea  in  his  work 
on  the  circulation.  Indeed  the 
conce[)tion  of  a  hierarchy  of 
the  organs  liardly  departed 
from  Biology  until  the  ob- 
servations of  Caspar  Friedrich 
Wolff  (1733-94)  and  Karl 
Ernst  von  Baer  (1792-1876) 
had     been     rationalized     by 

Fig.  7.  From  Regnier  de  Graaf's  Z>e  ^/M^ieru^i  Darwin,  SO  that  physiologists 
organis  genemtioni  inservientibus,  Leyden,  1672.  COuld  at  last  tum  from  the 
Illustrating  the  development  of  the  rabbit's  ovum  :  consideration  of  the  Orffan  tO 
1,  ova  on  the  third  day  after  conception,  2  on  the  ,  <•      -i 

fourth,  3  on  the  fifth,  4  on  the  sixth,  and  5  on  the    a    Contemplation     of     the     or- 

seventh  day.  The  remaining  figures  show  a  section  gailism,     and     liaturaUsts     be- 

of  the  tube  containing  two  embryos,  6  being  on  ^^^^^^   enabled  tO  think  of  the 

the  eighth  and  10  on  the  fourteenth  day.     The  •■,■.-,       ^  ,  i     j     •       • 

hist  figure  shows  the  placenta.  individual    not    aS    what    it    IS 

but  as  w^hat  it  has  been  and 
what  it  is  becoming.  Aristotle's  kinetic  view  was  at  length 
vindicated.- 

1  This  is  the  sense  of  Aristotle,  e.g.  De  generatione  animalium,  ii,  1  and  4  ; 
735^  25  and  738**  16.  The  phrase,  however,  primum  v'vens  ultimum  moriens  is, 
I  think,  first  used  in  Latin  translations  of  Averroes  (1126-98),  the  commentator 
on  Aristotle.  There  is  a  discussion  of  the  origin  of  the  phrase  in  the  Mitteihingen 
z.  Gesch.der  Med.  undXaturvcissenschaJten,  xix.  pp.  102, 219,  and  305,  Leipzig,  1920. 

^  There  is  a  discussion  of  ancient  embryological  literature  by  Bruno  Bloch, 
'  Die  geschichtlichen  Grundlagen  der  Erabryologie  bis  auf  Harvey  ',  inthe^6^an<Z- 
lungen  der  kais.  Leopold. -Carol.  Akad.,  Ixxxii,  pp.  213-334,  Halle,  1904.  There 
is  a  shorter  version  of  this  same  article  in  the  Zoologische  Annalen,  i,  p.  51, 
Wurzburg,  1905. 


THE   RISE   OF  MODERN   BIOLOGY  29 

IV.    Some  Aristotelian  Zoological  Observations  and  their 

Modern  Counterparts 

(a)  The  Placental  Shark 

We  may  now  turn  to  observations  in  the  Aristotelian  writings 
on  the  habits  of  animals  and  on  comparative  anatomy.  These 
are  far  too  numerous  for  extended  consideration  here,  and  we 
therefore  select  a  few  that  are  of  special  historical  interest  for 
comparison  with  their  modern  counterparts. 

Aristotle  recognized  a  distinction  in  the  mode  of  development 
of  mammals  from  that  of  other  viviparous  creatures.  Having  dis- 
tinguished the  apparently  viviparous  animals  as  either  truly  and 
internally  or  merely  externally  viviparous,  he  pointed  out  that  in 
the  mammalia,  a  group  regarded  by  him  as  internally  viviparous, 
the  foetus  is  connected  until  birth  with  the  wall  of  the  mother's 
womb  by  the  navel  string.  These  animals,  in  his  view,  produced 
their  young  without  the  intervention  of  an  ovum.  Such  non- 
mammals,  on  the  other  hand,  as  are  viviparous  are  so  in  the 
external  sense  only,  that  is,  the  young  which  arise  from  ova  may 
indeed  develop  withiii  the  mother's  body,  but  they  do  so  out  of 
organic  connexion  with  her,  so  that  her  womb  acts,  as  it  were,  but 
as  a  nursery  or  incubator  for  her  eggs.  It  was  thus  a  sort  of  accident 
whether  in  a  particular  species  the  ova  went  through  their  develop- 
ment inside  or  outside  the  mother's  body.  '  Some  of  the  ovipara ', 
he  says, '  produce  the  egg  in  a  perfect,  others  in  an  imperfect  state, 
but  it  is  perfected  outside  the  body  as  has  been  stated  of  fish.'  ^ 

But  it  is  exceedingly  interesting  to  observe  that  although 
Aristotle  regarded  fishes  as  a  whole  as  oviparous,  he  knew  also 
of  kinds  that 'were  externally  viviparous  and  he  knew,  further,  of 
one  instance  in  which  the  manner  of  development  bore  an  analogy 
to  that  of  his  true  internal  vivipara.  '  Some  animals  ',  he  says, 
'  are  viviparous,  others  oviparous,  others  vermiparous.  Some 
are  viviparous,  such  as  man,  the  horse,  the  seal  and  all  other 
animals  that  are  hair-coated,  and,  of  marine  animals,  the  ceta- 
ceans, as  the  dolphin,  and  the  so-called  Selachia.  Of  these  animals, 
some  have  a  tubular  air-joassage  and  no  gills  as  the  dolphin  and 
the  whale,  others  have  uncovered  gills,  as  the  Selachia,  the  sharks 
and  rays.  ...  Of  viviparous  animals  some  hatch  eggs  in  their  own 
interior  as  creatures  of  the  shark  kind  ;  others  engender  in  their 
interior  a  live  foetus,  as  man  and  the  horse.'  - 
1  De  Generatione  animalium.  iii.  9  ;  758^  37.       ^  Historia  animaUum,  i.  5  ;  489"  35. 


thp:  rise  of  modern  biology  :u 

He  even  attempts  to  give  an  explanation  of  this  j)cculiarity 
of  the  Selachians.  His  explanation  may  seem  to  modern  ears 
to  have  little  meaning,  just  as  many  of  our  scientific  explanations 
will  seem  meaningless  to  our  successors  in  a  generation  or  two. 
But  such  explanations  are  worth  recording  not  only  as  a  stage 
in  the  historical  development  of  biological  theory,  but  also  as 
illustrating  the  fact  that,  in  those  days  as  in  these,  while  the 
function  of  science  is  the  description  of  nature  its  motive  is  almost 
always  the  explanation  of  nature.  Yet  it  is  usually  the  descrij)- 
tive,  not  the  explanatory  element  that  bears  the  test  of  time. 

'  Birds  and  scaly  reptiles ',  says  Aristotle,  '  because  of  their 
heat  produce  a  perfect  egg,  but  because  of  their  dryness,  it  is 
only  an  egg,  the  cartilaginous  fishes  have  less  heat  than  these  but 
more  moisture,  so  that  they  are  intermediate,  for  they  are  both 
oviparous  and  viviparous  within  themselves,  the  former  because 
they  are  cold,  the  latter  because  of  their  moisture  ;  for  moisture 
is  vivifying,  whereas  dryness  is  furthest  removed  from  what  has 
life.  Since  they  have  neither  feathers  nor  scales  such  as  either 
reptiles  or  other  fishes  have,  all  which  are  signs  rather  of  a  dry  and 
earthy  nature,  the  egg  they  produce  is  soft ;  for  the  earthy  matter 
does  not  come  to  the  surface  in  their  eggs  any  more  than  in  them- 
selves. That  is  why  they  lay  eggs  in  themselves,  for  if  the  egg  were 
laid  externally  it  Avould  be  destroyed,  having  no  protection.'  ^ 

This  explanation  is,  of  course,  based  on  his  fundamental  doctrine 
of  the  opposite  qualities^  heat,  cold,  moistness  and  dryness  that  are 
found  combined  in  pairs  in  the  four  elements,  earth,  air,  fire,  and 
water. 

The  intermediate  character  of  the  Selachians  betAveen  the 
viviparous  and  the  oviparous,  as  set  forth  by  Aristotle,  was 
well  brought  out  by  Fabricius  ab  Aquapendente  ^  who  described 
and  figured  young  dogfish  attached  each  to  its  own  yolk  sac  and 
developing  within  the  uterus  of  the  mother  (Fig.  8).  But  Aristotle 
had  carried  his  investigation  farther  than  Fabricius,  for  he  knew 
of  that  small  group  of  Selachian  species  in  which  the  method  of 
nourishment  of  the  young  presents  remarkable  analogies  to  that 
of  the  placental  mammals.  In  this  group  of  fishes  the  wall  of  the 
yolk  sac  becomes  thickened  at  one  point  and  attached  to  a  corre- 
sponding thickening  in  the  wall  of  the  uterus.  In  this  way  a 
'  placenta  '  is  formed  very  similar  to,  though  not  homologous  with, 
the  mammalian  placenta,  and  the  little  developing  fish  derives 
nutriment  from  the  mother's  >  bod}^  through  the  placenta  and 
navel-string  much  as  in  a  mammal. 

^  De  generatione  animalium,  ii.  1  ;  733*  6. 

^  Hieronymus  Fabricius  ab  Aquapendente,  De  fonnalo  foetit,  Padua,  1004. 


:\2  (iKKIlK    KI()L()(i^     AM)    ITS    II  KLA'I'IOX    TO 

"  'I'iic  .so-callfd  sniootli  sliaik  ',  says  Aristotle  (Jaltod  he;  calls 
it,  and  tlu-  iiaiiic  is  still  \\si'(\  by  (^•('<'U  lishcnucii  -' ha.s  its  eggs 
in  hctwixt  the  wombs  like  llic  (l();i;-lisli  ;  these  e<<<^s  shift  into  ('a(,'h 
of  the  two  horns  of  the  wonil)  and  deseeiul,  and  the  young  develop 
with  the  navel-string  attached  to  the  womb,  .so  that  as  the  egg- 
substance  gets  used  up,  the  end)iyo  is  sustained  to  all  ap|)earanee 
just  as  in  (piadrupeds.  The  navel-string  is  long  and  adheres  to 
the  under  part  of  the  womb — eaeh  navel-string  being  attached 
as  it  were  by  a  sucker,  and  also  to  tlu;  centre  of  th(^  embryo  in 
tlu*  place  w'iiere  the  liver  is  situated.  If  the  embryo  is  cut  open, 
even  though  it  has  the  egg-substance  no  longer,  the  food  inside  is 
euii-like  in  ap|)earance.  Each  embryo,  as  in  the  case  of  quadrupeds, 
is  |)rovid(Ml  witli  a  chorion  and  separate  membranes.'  ' 

The  attachment  of  the  young  Selachian  to  the  womb  of  its 
mother    was    first    observed    in    modern    times    by   Pierre    Belon 


Fiu.  9.  Galeiis  laevis,  from  Rondelet's  De  piscibus  tnarinis,  Lyons,  1554. 
'  We  have  had  an  ilhistration  made  ',  says  Rondelet,  '  of  the  young  attached  by  the 
navel  cord  to  the  mother  so  that  it  may  be  distinguished  from  sea-dogs,  sea-wolves  and  the 
other  sharks,  as  there  is  no  other  shark  whose  young  is  covered  with  secundines  and  mem- 
branes and  attached  to  the  mother  by  a  navel  string.  I  am  aware ',  he  continues, '  that  there 
is  another  shark  with  a  smoother  skin  than  this  :  yet,  as  its  manner  of  reproduction  differs 
from  that  just  described,  I  assert  tliat  it  is  not  tlie  Galeus  laevis  of  the  ancients  but  rather  the 
Galeiis  glaucus  of  Aelian.     [JJe  imt.  ani)tuil.  i.  16.] ' 

(1517-1654)  in  1553  -  and  roughly  figured  by  Guillaume  Rondelet 
(1507-66)  in  1554^  {Fig.  9).  A  somewhat  similar  account  was 
given  by  the  missionary  du  Terte,  in  1667.^  The  description  of 
Belon  was  copied  by  Aldrovando  (1522-1607)  in  a  work  pubhshed 
in  1613  '  and  this  came  to  the  knowledge  of  Stensen,  who  definitely 
determined  the  relationship  of  the  Selachian  embrj^o  to  the  wall 
of  the  maternal  womb  in  1675. 

•  In  the  Galeus  laevis ',  says  Stensen,  '  each  foetus  has  its  own 
membrane  which  may  be  regarded  as  the  amnion,  since  like  the 

^  Historia  animalium,  vi.  10  ;  566'' 2. 

2  Pierre  Belon.  De  aqiiatilibus  cum  iconibus  ad  vivam  ipsorum  effigiem  quod 
fieri  potuit,  Paris,  1553,  p.  69. 

^  Guillaume  Rondelet,  De  piscibus  marinis,  Lyons,  1554. 

*  Jacques  du  Terte,  Histoire  generale  des  Antilles  habitees  par  les  FranQais, 
4  vols.,  Paris,  1667. 

5  Ulisse  Aldrovando,  De  jiiscibus,  Bologna,  1613,  p.  375. 


r»-. 


02- 


O 


-a 


tr. 


X 


x: 


On 


x; 


THE   RISE  OF  MODERN  BIOLOGY 


33 


stomacVi. 

v'belline  duct 
opening  info  int^sUm 


amnion  it  is  the  covering  of  the  foetus  and  floats  in  the  clear 
liquid.  Yet  it  differs  from  the  amnion  in  that  it  is  united  to  the 
placenta  in  the  way  characteristic  of  the  chorion  (in  mammals).  .  .  . 
There  is  only  a  single  very  small  placenta  to  each  foetus,  red  in 
colour  and  situated  close  to  the  lower  orifice  of  the  yolk  and 
a  membrane  drawn  over  forms  a  cavity. 

'  The  umbiUcal  vessels  pass  into  the  abdomen  of  the  foetus 
by  a  channel  beneath  the 
diaphragm  between  the 
two  anterior  lobes.  By 
following  this  duct  I  ob- 
served air  bubbles  floating 
in  the  intermediate  liquid. 
On  being  propelled  these 
disappeared  into  the  in- 
testine beyond.  Next  the 
intestine  of  a  second  foetus 
was  inflated,  and  while  I 
was  moving  it  in  different 
directions  I  opened  a  way 
for  the  air  towards  the 
placenta.  Thus  it  was 
evident  that  a  non-vascu- 


blo.cenrO' 
adherent 
Co  uterus 


vitelline  duct  opentnq 
into  cavity  abo^e  fhc 
.placenta. 


.^^ 


Fig.  10.  After  Stensen's  diagram  in  Ova  viviparorum 
•       1    J    J    spedantes  obsermtiones,  Copenhagen,  1675,  showing  re- 
lar      tube      was      included  lation  of  yolk  sac  to  umbilical  cord  and  intestine. 

among   the   vasa   umhili- 

calia  ;  of  this  vessel  one  extremity  was  joined  to  the  spiral  intestine 
within  the  abdomen,  the  other  to  the  placenta  where  its  upper 
surface  forms  a  cavity  with  a  thin  membrane  covering  it.  From 
the  structure  of  the  tube  it  is  evident  that  nourishment  is  brought 
to  the  intestine  from  the  cavity  of  the  placenta  in  this  fish  as  in 
birds  from  the  yolk,  as  long  as  food  is  supplied  to  the  foetus  by 
the  humours  of  the  mother.'  ^    (Fig.  10.) 

The  observations  of  Stensen  were  long  disregarded.  In  1828, 
Cuvier  in  his  great  work  on  fishes^  remarked  briefly  that  in 
Carcharias  the  yolk  sac  is  attached  to  the  uterus  as  firmly  as 
a  placenta.  Neither  Stensen  nor  Cuvier  referred  to  Aristotle  on 
this  subject,  and  the  importance  of  the  ancient  observations  was 
unappreciated  until  the  greatest  of  modern  morphologists,  Johannes 
Mtiller,  took  up  the  subject  in  1839.  Miiller  made  it  clear  that  there 
are  at  least  two  genera  of  Selachians  in  which  this  peculiar  placental 
development  takes  place,  namely  Carcharias  and  Musteliis  (Figs.  11- 

^  Nicolaus  Stensen,  Ova  viviparorum  spectantes  observationes,  in  T.  Bartholin's 
Acta  Hafniensia,  1675.  The  works  of  Stensen  have  been  made  accessible  by 
Vilhelm  Maar  in  his  Nicolai  Stenonis  Opera philosophica,  2  vols.,  Copenhagen,  1910. 
Cf .  ii,  p.  169. 

^  Georges  Cuvier,  Histoire  naturelle  des  Poissons,  Paris,  1828,  vol.  i,  p.  341. 

2391  n 


M  (UIKKK    BIOLOGY 

15).  Tlioro  can  hv.  little  doulit  from  Aristotlti'.s  doscriptioiis  tliat 
his  Oaleos  Icios  was  not  a  larger  sliark  lik(5  ('archari(i,s  but  a  sriiallcr 
dogfish  answi'iiiig  to  Miillor's  M asle.lus.  Miillcr  further  dcinoii- 
strated  the  very  peculiar  fact  that  within  the  geniiH  Muslelu8  one 
species  (J/,  laevis)  has  the  foetus  firmly  iniited  to  the  uterus  by 
means  of  a  placenta,  while  in  another  closely  allied  species  (M.  vul- 
<j(iris)  the  yolk  sac  is  quite  free  and  unattached.  It  is  interesting 
to  observe  that  the  distinction  between  the  two  allied  species  was 
quite  accurately  made  in  1554  by  Rondelet  (cf.  legend  to  Fig.  9). 

Johannes  Miillcr  describes  the  placenta  of  CUircharia.H  (Figs.  12 
and  13)  in  greater  detail  than  that  of  Muntclus  (Figs.  14  and  15). 

'  The  placenta  foetalis  of  these  fish  ',  he  says,  '  is  formed  by 
the  folded  yolk  sac.  The  folds  are  much  more  complex  in  Car- 
charias  than  in  Mustelus  laevis.  .  .  .  Tn  Carcharias  the  yolk  sac, 
as  usual,  possesses  two  coats,  an  internal  vascular  coat,  con- 
tinuous with  the  intestine  through  the  yolk  duct,  and  an  external 
non-vascular  coat  extending  as  a  sheath  over  the  yolk  duct  and 
the  omphalo-meseraic  vessels,  and  continuous  with  the  skin  of 
the  foetus.  ...  In  the  formation  of  the  placenta  both  membranes 
are  thrown  into  a  mass  of  folds  and  the  yolk  sac  thus  converted 
into  an  irregular  cavity.  These  folds  on  the  side  approximated  to 
the  uterus  become  closely  involved  with  the  wall  of  that  organ 
and  cannot  be  separated  except  by  some  force.  On  the  other 
hand  the  part  of  the  yolk  sac  on  the  side  away  from  the  uterus 
presents  mere  floating  diverticula.  Over  the  placental  area  the 
two  walls  of  the  yolk  sac  are  in  closest  contact  with  each  other, 
but  elsewhere  the  membranes  are  separated  from  each  other  by 
a  distinct  interval.  .  .  . 

'  The  placenta  uterina  is  formed  by  very  prominent  wrinkled 
folds  of  the  inner  membrane  of  the  uterus  which  accurately  corre- 
spond to  those  of  the  placenta  foetalis.  The  folds  of  both  are  inter- 
posed between  each  other,  and  are  as  closely  and  firmly  attached 
as  the  placenta  uterina  and  placenta  foetalis  of  any  mammiferous 
animal.  .  .  .  The  placenta  uterina  receives  its  blood-vessels  from 
the  uterine  vessels,  which  are  of  large  size,  and  run  to  the  seat 
of  the  placenta  at  the  lower  part  of  the  organ.  The  vessels  of  the 
placenta  foetalis  are  the  extraordinarily  large  vasa  omphalo- 
mesaraica  which  are  proportionally  of  as  great  size  as  the  vasa 
umbilicalia  of  mammals.  The  organic  relation  of  placenta  foetalis 
and  placenta  uterina  to  one  another  is  the  same  as  in  mammals.'  ^ 

^  Johannes  Miiller,  Handbuch  der  Physiologie  des  Menschen,  2  vols.,  Coblenz, 
1840,  vol.  ii,  p.  722.  See  also  translation  by  William  Baly,  Embryology,  with  the 
Physiology  of  Generation,  London,  1848,  p.  1597,  and  Johannes  Miiller  in  Monats- 
bericht  der  Akad.  der  Wissenschaften  zu  Berlin,  August  6,  1840,  Ueber  den  glatten 
Hai  des  Aristoteles,  Berlin,  1842,  and  in  Monatsbericht  d.  Berlin.  Akad.,  11th  April, 
1839. 


yolk,  tac  olta.ck- 
ed   Co  embruo 


Embryo  of  Mustdus  laevis  in  connexion 
with  the  uterus. 


Egg  of  jMusldits  vulgaris. 


Embryo  of  Mustelus  laevis,  7  lines  long,  with  the  placental  yolk  sac  separated  from  tlio  uterus. 

Fig.  11.    Embryos  of  two  species  of  Mustelus.     From  Johannes  Miiller,  Ueber  den  ijlatten 

Hai  des  Aristoteles,  Berlin,  1842. 
D  2 


AHTCAY    <  VEIN., 


INTESTINAL 
ARTERY  St 
VEIN 


Pio.  12.  Embryo  of  Carcharias  with 
umbilical  cord  and  placenta.  From 
Johannes  Midler. 


Fig.  13.  Dissection  of  umbilical  stnicturea  of  a  foetal 
Carcharias,  achematically  represented.  ModiBed  from 
Johannes  Miiller. 


unopened  vitcU 
sac  >Mith  urn 
cord  dtfiched 


vesicular  (aldiroi 
of  wjifof  virellini 
sac. 


cat  wdil  of  uter;* 


lawer  end  of  urerus 


cuf  edqsof 
vitelline  sac 

ain  vif^llihc  vttstt. 


vitelline  sac  laid  open 

branches  o^  vi^e!linc 
eacli  on  iurfdce  »f 
■icenta  ^oetalii 


Fig.  14.    A  part  of  the  uterus  of  Mustdus  laevis,  showing 
two  placental  attachments.     From  Johannes  Miiller. 


THE  RISE  OF  MODERN   BIOLOGY 


37 


Since  Miiller  wrote,  other  observers  have  brought  the  phe- 
nomenon of  the  placenta  of  Mustelus  and  Carcharias  more  into 
line  with  what  we  know  of  allied  viviparous  forms.  The  embryos 
of  many  of  these,  when  the  yolk  is  nearly  consumed,  are  nourished 
from  other  sources.    In  some  the  nutritive  material  is  secreted 


placenta,   utermc. 
placen ta  foetadi 


.inner    membrane   of  ute/u; 


umbilical    cord  . 

Fig.  15.    DIAGRAMJklATIC  SECTION  OF  PLACENTA  OF  MUSTELUS  LAEVIS. 
xModified  from  Johannes  Miiller. 

into  the  cavity  of  the  uterus  and  taken  into  the  mouth  of  the 
embryo  or  absorbed  by  the  blood-vessels  of  the  yolk  sac  or  of 
the  gill  shts.  In  others  the  wall  of  the  uterus  develops  secreting 
viUi  which  pass  through  the  spiracles  of  the  embryo  into  its 
pharynx.  In  yet  others  in  which  a  placenta  is  actually  developed 
the  process  of  absorption  is  aided  by  villi  which  stud  the  um- 
biUcal  cord  throughout  its  course.^ 

^  These  accessory  methods  are  described  in  the  following  papers  which 
contain  a  bibliography  of  the  subject :  Franz  Leydig,  Beitrdge  zur  mikroskopischen 
Anatomie    und   Eniwickelungsgeschichte  der   Rocken    und   Haie,    Leipzig,    1852  ; 


as       (;iu:kk  biolocjy  and  rrs  kklatton  to 

(b)   The  Rnwinanl  Stmnach 
Ainonp;  the  tnorc  roniarkahU^  of  Ari.stoth^'H  desc;ri|)tioiiH  in  the 
realm  of  coiiij)arativ('  anatomy  f)roper  iw  that  of  tlio  .stomach  of 
ruminants.     He  muat  have  diasected  these  animals,  for  he  gives 
a  clear  and  correct  account  of  the  four  chambers. 

'  Aiiinuils  ',  he  says,  '  present  diversiti(;s  in  the  structure  of 
their  stomachs.  Of  the  vivi])arous  quadrupeds,  sucli  of  the 
horned  animals  as  are  not  equally  furnished  with  teeth  in  both 
jaws  are  furnished  with  four  such  chambers.  These  animals  are 
those  that  are  said  to  chew  the  cud.  Jn  these  animals  the  oeso- 
phagus extends  from  the  mouth  downwards  along  the  lung,  from 
the  midriff  to  the  megale  koilia  [rumen,  or  paunch],  and  this 
stomach  is  rough  inside  and  semi-partitioned.  And  connected 
with  it  near  to  the  entry  of  the  oesophagus  is  what  is  called  the 
kekryphalos  [reticulum,  or  honeycomb  bag]  ;  for  outside  it  is  hke 
the  stomach,  but  inside  it  resembles  a  netted  cap  ;  and  the  kekry- 
phalos is  a  good  deal  smaller  than  the  megale  koilia.' 

The  term  kekryphalos,  the  reader  may  be  reminded,  was  applied 
to  the  net  that  women  wore  over  their  hair  to  keep  it  in  order. 

'  Connected  with  this  kekryphalos ',  he  continues,  '  is  the 
echinos  [jpsalteriu7n,  or  manyplies],  rough  inside  and  laminated,  and 
of  about  the  same  size  as  the  kekryphalos.  Next  after  this  comes 
what  is  called  the  enystron  [ahomasum'],  larger  and  longer  than  the 
echinos,  furnished  inside  with  numerous  folds  or  ridges,  large  and 
smooth.  After  all  this  comes  the  gut.'^  .  .  .  'All  animals  that  have 
horns,  the  sheep  for  instance,  the  ox,  the  goat,  the  deer  and  the 
like  have  these  several  stomachs.  .  .  .  The  several  cavities  receive 
the  food  one  from  the  other  in  succession  ;  the  first  taking  the 
unreduced  substances,  the  second  the  same  when  somewhat 
reduced,  the  third  when  reduction  is  complete,  and  the  fourth 
when  the  whole  has  become  a  smooth  pulp.'  ^  .  .  .  Such  is  the 
stomach  of  those  quadrupeds  that  are  horned  and  have  an 
unsymmetrical    dentition ;    and    these   animals    differ    one   from 

T.  J.  Parker  and  A.  Liversidge,  '  Note  on  the  foetal  membranes  of  Mustdus 
antarcticus  ',  Transactions  of  the  New  Zealand  Institute,  xxii,  p.  331,  Wellington, 
1890  ;  J.  Wood-Mason  and  A.  Alcock,  '  On  the  uterine  villiform  papillae  of 
Pteroplaiaea  micrura  ',  Proc.  Roy.  Soc,  xlix,  p.  359,  London,  1891  ;  J.  Wood- 
Mason  and  A.  Alcock,  '  Further  observations  on  the  gestation  of  Indian  Rays ', 
Proc.  Roy.  Soc,  1,  p.  202,  London,  1892  ;  A.  Alcock,  '  Some  observations  on  the 
embryonic  history  of  Pteroplaiaea  micrura,'  Annals  and  Magazine  of  Natural 
History,  sixth  series,  x,  p.  1,  London,  1892  ;  T.  Southwell  and  B.  PrashsMi, 
'  Embry ©logical  and  Developmental  Studies  of  Lidian  Fishes  ',  Records  of  the 
Indian  Museum,  xvi,  p.  215,  Calcutta,  1919. 

^  Historia  animalium,  ii.  17  ;  507*  33. 

2  De  partibus  animalium,  iii.  14  ;   674*^  6. 


I'l.ATK  XI.       iMom     15  lit.     Mus.     M.S.     Re--.   15    Kill     lo.    i  1    r 


Lc  Livre  des  Proprictcz  dc  Clums  translated   by  jelian  Corbechon   from   Latin 

of  Bartholomew  de  Glanvil,  written  at   Bruges  b\'  Jehan  du   Ries 

in  1482.     Frontispiece  of  Book  XII   'On   Birds'. 


1^ 

CO 


00 
o 


o 

lO 


O 
(f) 

H 

C 

< 
> 


'^z- 


CO 

m 

o 


< 

Oh 


THE  RISE  OF  MODERN  BIOLOGY 


39 


A.OIlulanncdiiintcrniccircrata,Ariftotcliiii«^/'9a>.®-. 
E.PcniiUlivc.-per«  iC(.>,'«  Arifliotcli.  C.  ConcUvecel- 
luUcum;^!!^  Arift.  D.  V'encriculus(propriidiOus) 
in(c(liniiis/imiluao.Atift.v>$7"      E.Lt^ancii 


Fig.  16. 


another  in  the  shape  and  size  of  tlie  parts,  and  in  the  fact  of  the 
oesophagus  reaching  the  stomach  centralwise  in  some  cases  and 
sideways  in  others.  Animals  that  are  furnished  equally  with  teeth 
in  both  jaws  have  one  stomach  ;  as  man,  the  pig,  the  dog,  the 
bear,  the  lion,  the  wolf.'  ^ 

The  general  appearance  of  the  stomach  of  ruminants  must 
always  have  been  roughly  known  to  butchers  and  its  rediscovery 
cannot  therefore  be 
dated  as  can  many 
of  the  biological  ob- 
servations of  Aris- 
totle that  we  have 
to  recount.  A  fair 
scientific  description 
of  the  organ  was 
made  by  Aldrovando 
in  1613"  and  by  Fa- 
briciusin  1618.^  The 
ruminant  stomach 
was  figured  imper- 
fectly by  Severino  in 
1645^  (Fig.  16),  and 
by  Blasius  in  1667." 
There    is    a     better 

figure  by  Grew  of  1681^  (Fig.  17),  and  an  excellent  painting  was 
prepared  by  Tyson,  the  earliest  English  comparative  anatomist, 
in  1687  (Plate  xii). 

(c)  The  Generative  processes  of  Cephalopods 
Nowhere  is  the  contrast  between  the  ancient  and  modern 
method  of  setting  out  biological  conclusions  better  brought  out 
than  in  the  investigation  of  the  extraordinarily  interesting  genera- 
tive processes  of  the  Cephalopods.  An  examination  ^f  the  modern 
accounts  of  the  subject  enables  us  to  observe  the  slow  emergence 
of  a  true  conception  of  the  actual  nature  of  the  phenomena.    This 

1  Historia  animalium,  ii.  17  ;   507"  12. 

-  Ulisse  Aldrovando,  Qvxidrupedium  omnium  bisulcorum  historia,  Bologna,,  1613. 

^  Hieronymo  Fabricius,  De  gula,  Padua,  1618. 

*  Marco  Aurelio  Severino,  Zootomia  Democritea  id  est  Anatome  generalis  totius 
animantium  opificii,  libris  quinque  distincta,  Nuremberg,  1645. 

^  Gerhard  Blaes,  Observata  anatomia,  Amsterdam,  1676,  p.  49. 

^  Nehemiah  Grew,  Catalogue  of  the  rarities  belonging  to  the  Roijal  Society, 
London,  1681. 


THE    FOUR    CHAMBERS    OF    THE 
STOMACH    OF    A    LAMB 


From  Marco  Aurelio  Severino,  Zootomia  Democritea, 
Nuremberg,  1645. 


40 


(JRKKK    I^IOLOOY  AND   ITS   IIEJ.ATION  TO 


Jkt  StfmtiL)  and  On 
et  a  Slutf. 


process  contimus,  iji  spite  of  many  errors,  because  each  observer 
records  liis  actual  observations  and  places  them  in  sucli  a  form 
that  tlio  place,  time  and  means  of  observation  can  be  referred  to 

fit  need,  and  the  reader 

Ct\\(^^i(s\({\(t\  ^^^^    himself    se))arate 

what  is  observed  from 
what  is  inferred  and 
can  grasp  not  only  the 
nature  of  the  observa- 
tion itself  but  the 
means  by  which  it  was 
made.  Thus  the  work 
of  each  writer  can  be 
criticized  or  modified 
by  the  next.  In  doing 
this  both  \\Titer  and 
reader  are  immeasur- 
ably aided  by  the  use 
of  figures.  It  is  true 
that  diagrams  were 
used  also  by  xA.ristotle,^ 
but  these  appear  to 
have  been  merely  occa- 
sional devices  rather 
than  an  intrinsic  part 
of  his  method.  Draw- 
ings or  diagrams  as 
routine  aids  to  biologi- 
cal descriptions  w^ere 
probably  uncommon 
until  the  first  century 
B.C.  In  his  account 
of  the  generative  jDro- 
cesses  of  the  Cephalo- 
pods  the  ancient  na- 
turalist records  only  the  final  conclusions,  and  w^e  hardly  know 
which  of  the  observations  are  his  ow^n  and  w^hich  are  taken  from 


Fig.    17.        THE       F  O  U  R- C  H  AM  B  E  R  E  D 
STOMACH    OF    A    SHEEP 
After  Nehemiah  Grew,  The  Comparative   Anatomy  of  the 
Stomach  and  Guts  Begun,  London,  1681. 


1  An  interesting  reference  to  the  diagrams  in  Aristotle's  lost  work  on  Anatomy 
will  be  found  in  the  Historia  animalium,  i.  17  ;  497^  33.  Other  references  to 
anatomical  diagrams  are  in  the  De  generatione  animalium,  ii.  7  ;  746^^  14,  and  the 
Historia  animalium,  iii.  1  ;  510^29.     The  words  used  are  (rxiqiJ^a-ra,  kay pacfty},  and 

7rapaE€Lyfj.aTa. 


THE  RISE  OF  MODERN   BIOLOGY  41 

others,  while  he  tells  us  nothing  whatever  of  the  conditions  under 
which  they  were  made.  In  spite  of  these  faults  in  the  record, 
his  descriptions  impel  conviction  that  they  are  those  of  an  acute 
and  accurate  observer,  and  that  his  work  does  not  suffer  from  any 
lack  in  his  powers  as  a  naturalist.  The  main  references  to  the 
reproduction  of  Cephalopods  occur  however  in  the  ninth  book  of 
the  Historia  animalium,  which  is  of  more  doubtful  authenticity 
than  the  earlier  parts. 

With  regard  to  the  Cephalopod  Argonauta  Aristotle  says  that 
it  is  an 

*  octopus,  but  one  pecuHar  both  in  its  nature  and  habits.^  .  .  . 
This  polypus  lives  very  often  near  to  the  shore,  and  is  apt  to  be 
thrown  up  high  and  dry  on  the  beach  ;  under  these  circumstances 
it  is  found  with  its  shell  detached,  and  dies  by  and  by  on  dry  land.^ 
...  It  rises  up  from  deep  water  and  swims  on  the  surface.  In 
between  its  feelers  it  has  a  certain  amount  of  web-growth  resem- 
bling the  substance  between  the  toes  of  web-footed  birds ;  only  that 
with  these  latter  the  substance  is  thick,  while  with  the  nautilus  it 
is  thin  like  a  spider's  web.  (Cf.  Plate  xiii.)  It  uses  this  structure, 
when  a  breeze  is  blowing,  for  a  sail,  and  lets  down  some  of  its  feelers 
alongside  as  rudder-oars.  (Cf.  Fig.  18,  p.  43.)  If  it  be  frightened 
it  fills  its  shell  with  water  and  sinks.  With  regard  to  the  mode 
of  generation  and  the  growth  of  the  shell,  knowledge  is  not  yet 
satisfactory  ;  the  shell,  however,  does  not  appear  to  be  there  from 
the  beginning,  but  to  grow  in  their  case  as  in  that  of  the  other 
shell-fish ;  neither  is  it  ascertained  for  certain  w^hether  the  animal 
can  live  when  stripped  of  the  shell.'  ^ 

The  use  of  the  membranes  of  the  Argonaut  as  a  sail  and  the 
arms  as  oars  (Fig.  18)  is  now  known  to  be  pure  myth,  though  many 
excellent  naturalists,  Verany  among  them,  have  given  colour  to 
one  or  other  of  these  ideas.  It  is  but  right  to  emphasize  again 
that  the  ninth  book  of  the  Historia  animalium,  in  which  the  state- 
ment occurs,  is  probably  not  the  work  of  Aristotle  himself.^ 

The  questions  that  the  Aristotelian  treatise  asks  about  the 
Argonaut  can  now  at  last,  after  many  centuries,  be  answered  in 
some  fullness,  although  observation  of  the  animal  has  been  beset 
with  numerous  difficulties.  It  is  a  fact  that  the  shell  is  not 
necessary  to  its  life,  and  Lacaze-Duthier  observed  it  he  animal 
recover  the  shells  which  had  been  taken  from  it.  The  shell  when 
fully  formed  is  in  no  organic  connexion  with  the  body  of  the 

^  Historia  animalium,  ix.  38  ;  622*^5.        -  Historia  animalium,  iv.  2  ;  525*22. 
^  Historia  animalium,  ix.  3S  ;  622'' 6. 

^  On  the  question  of  the  authenticity  of  the  ninth  book  of  the  Historia  anima- 
lium, see  H.  Aubert  and  F.  Wimmer,  Aristotelis  Thierkunde,  Leipzig,  1868,  p.  11. 


42       (;ri:kk  biology  and  its  relation  to 

animal,  ajid  its  luiictiuii  i.s  but  to  siipjxjit  and  acratt-  tlic  developing 
eggs  ;  it  has  tlierefore  boon  aptly  coni|)ared  to  a  i)ei'anibulator. 
The  animal  does  not  willingly  .sink  below  the  Hurface  of  the  water, 
and  if  foreed  to  do  so  will  rise  again,  and  it  is  indeed  doubtful 
if  it  is  able  to  sink  at  all  by  its  own  ellort.  The  act  of  congress 
has  not  been  seen  in  this  species,  though  since  the  aj)pearance  of 
the  work  of  Heinrich  Miiller,  the  male,  which  is  much  smaller 
than  the  female,  has  been  recognized.     (Plate  xiii.) 

Turning  now  to  the  descrij)tion  given  of  the  sexual  processes 
of  cephalo])ods  by  the  naturalist  of  antiquity  we  read  that 

'  The  Malacia  such  as  the  octopus,  the  sepia  and  the  calamary, 
have  sexual  intercourse  all  in  the  same  way  ;  that  is  to  say,  they 
unite  at  the  mouth  by  an  interlacing  of  their  tentacles.  When, 
then,  the  octopus  rests  its  so-called  head  against  the  ground  and 
spreads  abroad  its  tentacles,  the  other  sex  fits  into  the  outspreading 
of  these  tentacles,  and  the  two  sexes  then  bring  their  suckers  into 
mutual  connexion.  Some  assert  that  the  male  has  a  kind  of  penis 
in  one  of  his  tentacles,  the  one  in  which  are  the  largest  suckers ; 
and  they  further  assert  that  the  organ  is  tendinous  in  character, 
growing  attached  right  up  to  the  middle  of  the  tentacle,  and  that 
the  latter  enables  it  to  enter  the  nostril  or  funnel  of  the  female.'  ^ 

It  is  unfortunate  that  since  he  has  given  this  accurate  descri[)- 
tion  Aristotle  elsewhere  contradicts  it. 

'  In  the  cephalopods  ',  he  says,  '  the  same  passage  serves  to 
void  excrement  and  leads  to  the  part  like  a  uterus,  for  the  male 
discharges  the  seminal  fluid  through  this  passage.  And  it  is  on 
the  lower  surface  of  the  body  where  the  mantle  is  open.  .  .  .  Hence 
the  union  of  the  male  with  the  female  takes  place  at  this  point. 
.  .  .  But  the  insertion,  in  the  case  of  the  poulps,  of  the  arm  of  the 
male  into  the  funnel  of  the  female,  by  which  arm  the  fishermen  say 
the  male  copulates  with  her,  is  only  for  the  sake  of  attachment,  and 
it  is  not  an  organ  useful  for  generation,  for  it  is  outside  the  passage 
in  the  male  and  indeed  outside  the  body  of  the  male  altogether.'  '^ 

We  may  now  turn  to  the  rediscovery  in  modern  times  of  that 
peculiar  sexual  process  of  the  octopods  known  as  hectocotylization 
which  explains  Aristotle's  description  and  even  his  self-contra- 
diction concerning  the  cephalopods.  The  story  may  be  given  in 
the  words  of  one  of  the  most  eminent  investigators  of  these 
creatures,  Richard  Ow^en.  The  discussion  concerning  the  nature 
of  the  process  of  fertihzation  arose  chiefly  in  connexion  with  the 
octopod  known  as  Argonauta  Argo. 

^  Historia  animalhim,  v.  6  ;  54P  1. 

2  De  generatione  animalium,  i.  15  ;   720*^  25. 


p  L  A  r  !•:   XIII 


tt^ 


Female  argonaut  from  H.  de  Lacazc-Duthiers,  Archives  dc  Zooloqic  e.xpiriiiiciilnle,  1892. 

The  animal  is  seen  in  profile  and  the  arrow  shows  the  direction  of  movement.  />', 
mouth  with  parrot-like  beak.  Tr,  the  nidamental  shell  projecting  beyond  the  two 
specially  developed  shell-carr3Mng  arms  Br. p.  If  the  outline  of  the  shell  is  followed  it 
will  be  seen  to  project  beyond  the  shell  membrane  /',  also  at  C.  En,  the  funnel  pro- 
jecting between  the  two  anterior  arms,  Br.'i. 


li...  I. 


Male  argonaut  from  Ileinrich  MiiUer.  Zeilschriftftir  ivisscnschaflliclic  Zoologir,  1853. 
The  second  and  fourth  arms  of  the  left  side  2    Heotocotylus  unfolded  showing  how  the  sac  is 

are  depressed  to  show  the  hectocotylus  sac. 


formed  as  a  membrane  developed  at  base  of  arm. 


r  I.  A  r  i:    x  i  v 


H  E  C  T  O  C  O  7  ^'  L  I  Z  A  T  I  O  N 

From  J.  B.  Vc-rany,  1851  ;  1-3.  Oc/opiis  careiiae of  \'eiany  ;  i,  Hectocotylus  extended  : 
2,  in  sac  ;  3,  removed  from  sac  ;  4-5,  Hictocotylus  ociopodis  of  Cuvier,  1829  ;  6,  Triclio 
cephalus  acetobidaris  of  Delle  Chiaje,  1828  ;  lb  alimentar}'  canal,  c  ovary,  d  pigmented 
membrane,  c/ suckers  ;  7-8,  Alleged  male  of  Argonaut  from  Costa.  1841  ;  ab  trunk, 
cc  terminal  appendix,  ef  tentacular  cirrhus,  /  suckers,  //  mucous  sac,  d  membrane 
with  special  strands. xx:  lo-ii,  Hectocotylus  Argonaiitae oi  Kolliker,  1849  (see  text  figs. 
19-21) ;  13-14  Hectocotylus  of  Ticuwctopiis  liolaccits  of  Veranj'  after  Kolliker,  figured 
by  the  latter  as  a  separate  animal,  e  spermatic  duct,/ testis,  g  penis. 


THE  RISE  OF  MODERN  BIOLOGY 


4:i 


'  The  cumulative  experience  of  numerous  observers  since 
1839  ',  says  Owen,  writing  in  1855,  '  had  led  to  the  conviction 
that  the  Argonauta  with  the  expanded  arms  and  shell  was  the 
female  form  of  the  species.  The  discovery  of  the  male  has  been 
attended  with  difficulties.  .  .  . 

'  Delle  Chiaje  first  (1828)  figured  and  described  an  organism 
which  he  found  attached  to  the  female  Argonaut,^  and  which  he 
believed  to  be  a  parasite,  describing  it  under  the  name  of  Tricho- 
cephalus  acetabularis  (Plate  xiv,  item  6)  on  account  of  the  number 

Portrai'cl  du  Nautillusjc^ucl  Pline  nome  Poj^ilusou  Nauj^lius. 


Fig.  18.     THE     PAPER     NAUTILUS 

Argorlauta  Argo.     From  Belon's  Histoire  naturdle  des  estranges  poissons,  Paris,  1551.     The 
animal  is  drawn  as  though  using  its  arms  as  oars  and  its  membrane  as  a  sail. 

of  suckers  with  which  it  was  beset.  In  the  following  year,  Cuvier, 
having  received  a  similar  organism  which  Laurillard  had  detected 
in  a  cephalopod  called  Octopus  granulosus,  also  beheved  it  to  be 
a  parasitic  worm  for  which  he  proposed  the  name  of  Hectocotylus 
Octopodis,  assigning  the  name  Hectocotylus  Argonautae  to  the 
previously  observed  species.^  (Plate  xiv,  items  4  and  5.)  In  1842 
KoUiker,  having  detected  the  same  organism  apparently  parasitic 
on  the  female  Argonaut,  carefully  scrutinized  its  structure  and 
found  that  of  the  skin,  with  its  complex  pigment  cells  and  that 
of  the  acetabula,  identical  with  the  same  parts  in  the  Argonaut. 
He  detected,  moreover,  in  a  dilated  hollow  part  of  the  organism 
a  quantity  of  spermatozoa  .  .  .  and  came  to  the  bold  conclusion 

*  Stefano  delle  Chiaje,  Memorie  sulla  storia  e  notomia  degli  animali  senza  vertebre 
del  regno  di  Napoli,  4  vols,  and  2  atlases,  Naples,  1828,  vol.  ii,  Plate  16. 

2  Georges  Cuvier, '  Memoire  .sur  un  ver  parasite  d'un  nouveau  genre  {Hectocotylus 
octopodis) ',  in  the  Annales  des  sciences  natiirelles,  xviii,  Paris,  1829,  p.  147,  plate  11. 


44 


GREEK   BI()I.()(;Y   AND    ITS   PvKLATION  TO 


that  it  was  tlic  lon^-soii^ht-for  niah^  of  i\\r.  Aif^oiiaiit,  arrested  in  its 
(leveIo])in(Mit  and  sid).si.stijig  |)iacti(;ally  para.sitioally  on  tlie  female, 
like  the  diminutive  males  of  the  Kotifera,  E])izoa,  and  Cirrhipedia. 
it   may   servo   as   a   wholesome   warning   against   entering   upon 


Aider  tor  e/id 
of  body 


natural  positm 


Membranous 
process  of 
appendix 

Posterior  e/id 
of  bo<fy 


Orifice  at  poskrior 
end  of  dorsal  crest 


Vtntral  surface 

Fig.  19. 


\.  Vrniral 
r  surface 


Anterior  end  of  body 

( 


Ventral  surface 


Appendix  pulled, 
awa^  front  the 
cxipsuh  of  the 
Posterior  out  of  body    ^^^' 


Fig.  20. 

Figs.  19,  20.      DRAWING    FROM    KOLLIKER     OF    THE 

'MALE    ARGONAUT' 

a  scrutiny  of  parts  while  prepossessed  by  a  foregone  conclusion  to 
remember  that  the  acute  and  usually  accurate  observer  describes 
the  digestive,  circulatory,  and  respiratory  organs  of  the  same 
supposed  independent  individual  male  animal.'  ^  (Figs.  19-21  and 
Plate  XIV,  items  10,  11,  13,  and  14.) 

*  Albrecht  von  Kolliker,  '  Hectocotylus  Argonautae  D.  Ch.  und  Hectocotylus 
Tremoctopodis   Koll.,  die  Mannchen   von   Argonauta  Argo   und  Tremoctopus 


THE  RISE   OF  MODERN   BIOLOGY 


45 


Cut  gjdgt  of 
dorsal  crest 


Penis 


'  Verany  first  had  the  good  fortune  to  discover  the  Hecto- 
cotylus  or  presumed  parasitic  male  Argonaut,  forming  one  of  the 
arms  singularly  modified  and  developed,  of  a  little  octopod  which 
he  figured  under  the  name  of  Octopus  carenae  (Plate  xiv,  items 
1-3).^  Miiller  and  others  were  not  slow  in  demonstrating  that 
this,  or  a  similarly  modified  octopod,  was  really  the  male  of  the 
Argonauta  -  (Plate  xiii). 

'  Certain  species  of  the  Octopod  family  thus  have  the  male 
apparatus  extended  into 
one  of  the  cephalic  arms. 
...  In  Octopus  granulosus 
and  Argonauta  Argo  the 
spermatic  duct  is  continued 
from  the  testis  .  .  .  into  the 
base  of  the  sexual  arm  and 
opens  into  a  dilated  reser- 
voir at  the  termination  of 
that  singularly  modified 
member.  It  is  somewhat 
longer  than  the  longest  of 
the  unmodified  arms,  and 
is  much  thicker.  The  ace- 
tabula  are  larger  and  more 
numerous,  but  retain  the 
arrangement  in  a  double 
row.  .  .  . 

'  One  presumes  that  the 
arms  of  the  two  sexes  being 
interlaced,  as  described  by  Aristotle,  the  expanded  receptacular  end 
of  the  modified  arm,  with  the  spermatozoa,  is  introduced  into  the 
funnel  of  the  female  .  .  .  and  that  .  .  .  the  modified  arm  is  snapped 
off  and  left  adhering  to  the  female  by  the  suckers  where  it  long 
retains  the  power  of  motion.  Such  is  the  conclusion  of  the  long 
mooted  questions  of  the  Argonaut,  its  shell,  the  use  of  the  brachial 
membranes  as  '  sails  ',  and  the  true  sexual  distinctions  of  the 
male  and  female.'  ^ 


Opemng  of  perws 
Capsule  of  testis 


Free  edge  of  dorsal 
crest 

Posterior  unopened 
portion  of  dorscd. 
crest 


Orifice  en 
dorsal  crest 


Seminal  tube 


Stminal  tube 


Appendix  (from  tvhich 
memhranous  process 
lias  been  removed)  in. 
(Is  natural  position 


Fig.  21.    DISSECTION  OF  THE  '  MALE 
ARGONAUT'.     After  Kolliker. 


violaceus  D.  Ch.',  in  the  Berichte  von  der  zootomischen  Anstalt  in  Wurzburg  fiir  das 
Schuljahr  1847-8,  Leipzig,  1849,  p.  67.  This  article  is  exceedingly  rare,  but  there 
is  a  copy  in  the  collection  of  T.  H.  Huxley  at  the  Royal  College  of  Science,  London. 

^  J.  B.  Verany,  Mollusques  mdditerraniens,  Genoa,  1851,  and  '  Memoire  sur  les 
hectocotyles  de  quelques  Cephalopodes '  in  the  Annales  des  sciences  naturelles,  xvii. 
Paris,  1852. 

^  Heinrich  Miiller,  '  Ueber  das  Mannchen  von  Argonauta  Argo  und  die 
Hectocotylen  '  in  the  Zeitschrijt  fiir  wissenschaffUche  Zoologie,  vol.  iv,  Leipzig, 
1853,  p.  1. 

^  Richard  Owen,  Lectures  on  the  Anatomy  and  Physiology  of  the  Invertebrates, 
2nd  edition,  London,  1855,  pp.  628  ff. 


46  GKKKK    BIOLOCiY    AND    ITS    IIKLATION   TO 

Tt  remains  only  to  mUI  tliat  th(5  actual  |)roc('SM  of  congrefis 
of  an  octopus,  tliough  not  of  Aifjonauta  its(^lf,  lias  been  watched  by 
Racovitza  (Fig.  22)  and  the  lu^ctocotylizcul  arm  of  the  male  has 
been  observed  to  be  inserted  through  the  mantle  and  into  the 


Fig.  22.     CONGRESS    OF    OCTOPUS    VULGARIS 

as  observed  in  a  tank  by  IC.  Racovitza,  Archives  de  Zoologie  experimentale,  Serie  ii,  Paris. 

1894.    The  male  is  seen  to  the  right.    He  has  fixed  himself  by  the  bases  of  his  arms  to  the 

glass  of  the  aquarium  and  has  introduced  the  extremity  of  the  hectocotylized  arm  into  the 

pallial  cavity  of  the  female  to  the  left. 

funnel  of  the  female.^  There  is  still  a  gap  in  our  knowledge 
however,  for  the  passage  of  the  fertilizing  elements  from  the  testis 
into  the  arm  of  the  male  has  not  yet  been  observed. 


(d)  The  Habits  of  Animals 
i.  The  Frog -fish  and  Torpedo 
Aristotle  is  perhaps  at  his  best  and  happiest  when  describing 
the  habits  of  Uving  animals  that  he  has  himself  observed.  Among 
his  most  pleasing  accounts  are  those  of  the  fishing-frog  and  torpedo. 
In  these  creatures  he  did  not  fail  to  notice  the  displacement  of  the 
fins  associated  with  the  depressed  form  of  the  body. 

'  In  the  Torpedo  and  the  Fishing-frog,'  he  says,  '  the  breadth 
of  the  anterior  part  of  the  body  is  not  so  great  as  to  render  loco- 
motion by  fins  impossible,  but  in  consequence  of  it  the  upper 
pair  [pectorals']  are  placed  further  back  and  the  under  pair  \yen- 
trals]  are  placed  close  to  the  head,  while  to  compensate  for  this 
advancement  they  are  reduced  in  size  so  as  to  be  smaller  than  the 
upper  ones.  In  the  Torpedo  the  two  upper  fins  [pectorals]  are 
placed  in  the  tail,  and  the  fish  uses  the  broad  expansion  of  its 

^  ifimile  Racovitza, '  Notes  de  biologic  '  in  the  Archives  de  zoologie  experimentale, 
series  3,  vol.  ii,  Paris,  1894,  p.  25. 


THE  RISE  OF  MODERN  BIOLOGY  47 

body  to  supply  their  place,  each  lateral  half  of  its  circumference 
serving  the  office  of  a  fin.'  * 

'  In  marine  creatures  one  may  observe  many  ingenious  devices 
adapted  to  the  circumstances  of  their  lives.  For  the  account 
commonly  given  of  the  frog-fish  or  angler  is  quite  true  ;  as  is  also 
that  of  the  torpedo.  The  frog-fish  has  a  set  of  filaments  that 
project  in  front  of  its  eyes  ;  they  are  long  and  thin,  like  hairs, 
and  are  round  at  the  tips  ;  they  lie  on  either  side,  and  are  used  as 
baits. ^  .  .  .  The  little  creatures  on  which  this  fish  feeds  swim  up  to 
the  filaments,  taking  them  for  bits  of  seaweed  such  as  they  feed 
upon."*  Accordingly,  when  the  animal  stirs  himself  up  a  place 
where  there  is  plenty  of  sand  and  mud  and  conceals  himself 
therein,  it  raises  the  filaments,  and  when  the  little  fish  strike 
against  them  the  frog-fish  draws  them  in  underneath  into  its 
mouth.  The  torpedo  narcotizes  the  creatures  that  it  wants  to 
catch,  overpowering  them  by  the  force  of  shock  that  is  resident 
in  its  body,  and  feeds  upon  them  ;  it  also  hides  in  the  sand  and 
mud,  and  catches  all  the  creatures  that  swim  in  its  way  and  come 
under  its  narcotizing  influence.  This  phenomenon  has  been  actually 
observed  in  operation.  .  .  .  That  the  creatures  get  their  living  by 
this  means  is  obvious  from  the  fact  that,  whereas  they  are  peculiarly 
inactive,  they  are  often  caught  with  mullets,  the  swiftest  of  fishes, 
in  their  interior.  Furthermore,  the  frog-fish  is  unusually  thin  when 
he  is  caught  after  losing  the  tips  of  his  filaments,  while  the  torpedo 
fish  is  known  to  cause  a  numbness  even  in  human  beings.'  ^ 

The  Fishing-frog  is  well  known  in  northern  waters  and  several 
of  the  early  naturalists  give  recognizable  figures  of  it  (Fig.  23). 
It  is  remarkable  how  in  most  of  them  a  curious  error  has  crept  in 
as  regards  the  structure  of  the  fins.  The  pectoral  limbs  of  the 
Lophiidae  are,  in  fact,  specially  developed  for  crawHng  about  on 
the  sea  floor.  In  the  older  pictures,  however,  the  fins  are  usually 
represented  as  divided  into  digits,  a  mistake  perpetuated  in 
the  careful  paintings  of  dissections  of  this  creature  that  have 
been  left  by  Edward  Tyson  (1650-1708) '  (Plate  xii). 

The  peculiar  action  of  the  Torpedo  described  by  Aristotle 
has  been  the  subject  of  a  number  of  classical  investigations  and 
has  been  brought  into  line  with  widely  distributed  phenomena. 
It  is  characteristic  of  muscle  substance  that  at  the  moment  of 
contraction   it   produces   an   electric   disturbance.      In   ordinary 

^  De  partibus  animalium,  iv.  13  ;  696*26. 

2  Historia  animalium,  ix.  37  ;  620''  10. 

3  This  passage  only  doubtfully  refers  to  the  fishing-frog.  We  have  transposed 
it  from  ix.  37  ;  620"  30.  *  Historia  animalium,  ix.  37  ;  620''  15. 

^  Drawings  of  these  dissections  are  found  in  MSS.  of  Tyson  at  the  Royal 
College  of  Physicians  of  London,  and  at  the  British  Museum. 


48 


(;|{KKK    BIOLOdN     AND    ITS    liKLATiUN    TO 


muscular  tissue  tliis  can  only  be  (Ictcctcd  by  means  of  delicate 
instruments,  but  in  the  Torpedo-lish  there  are  two  tracts  of  muscu- 
lature which  show  a  reduction  of  the  function  of  contraction 
accompanied  by  a  great  increase  in  the  power  of  producing  electric 
disturbance.  These  electric  organs  are  two  large  kidney-shaped 
structures  occupying  the  greater  portion  of  the  forepart  of  the 
animal  and  are  controlled  by  a  special  set  of  nerves  which  have  their 
origin  in  a  characteristically  developed  lobe  of  the  brain  (Fig.  24). 

FETRI        BElLONtr        CENOMANI 

B«t3;p«iMf ')aAa7?iof,Crxci$:Rana  manna, Latini$:D(4«o/o»)»4n/»o,[taliK 


Fig.  23.     THE    FROG-FISH 
From  Pierre  Belon's  De  aquatilibus,  Paris,  1553. 

Ai'istotle  was  by  no  means  alone  among  the  ancients  in  his 
knowledge  of  the  electric  action  of  the  torpedo.  The  animal  was 
commonly  eaten  and  is  referred  to  as  suitable  for  invalids  in 
several  of  the  Hippocratic  treatises  (fifth-fourth  cent,  b.c.).^  Tor- 
pedo and  fishing-frog  were  both  known  to  PUny  (c.  a.  d.  23-79),  and 
it  is  worth  repeating  his  account  of  these  fishes,  copied  evidently 
from  Aristotle,  in  Philemon  Holland's  inimitable  translation : 

'  I  marvel ',  he  writes,  '  at  them  who  are  of  opinion  that  fishes 
and  beasts  in  the  water  have  no  sence.  \Vhy,  the  very  Crampe-fish 
Tarped  (i.  e.  Torpedo)  knoweth  her  oune  force  and  power,  and 
being  herselfe  not  benummed,  is  able  to  astonish  others.  She 
heth  hidden  ouer  head  and  ears  within  the  mud  unseene,  readie 
to  catch  those  fishes,  which  as  they  swim  ouer  her,  bee  taken  with 

1  In  the  De  vidus  ratione,  a  work  in  part  older  than  Hippocrates,  in  the 
spurious  but  ancient  De  inter nis  affectionibus,  and  in  the  equally  ancient  and 
spurious  De  mulierum  morhis. 


THE   RISE   OF  MODERN  BIOLOGY 


49 


a  nummednesse,  as  if  they  were  dead.  Also  the  fish  called  the 
sea  Frog,  Diable  de  Mer,  (and  of  others,  the  sea  Fisher)  is  as 
craftie  everie  whit  as  the  otlier  :  It  puddereth  in  the  mud,  and 
troubleth  the  water,  that  it  might  not  bee  seene  :    and  when  the 

electric   organ 
-Ajrebrain. 
,mi<i  brain 
spiracle 
-cerebellum 


nerve  passing 
from  electric 


electric    (obe 

common  moscula' 
_  .  ih«ath   covtfpin^ 
branchial  cleats. 


_  branchial    &ae& 


Fig.  24.  THE  ELECTRIC  ORGAN  OF  THE  TORPEDO 

little  seely  fishes  come  skipping  about  her,  then  she  puts  out  her 
little  homes  or  Barbils  which  shee  hath  bearing  forth  under  her 
eies,  and  by  little  and  little  tilleth  and  tolleth  them  so  neere  that 
she  can  easily  seaze  upon  them.'  ^ 

The  torpedo  must  have  been  somewhat  extensively  experi- 
mented upon  in  antiquit3\  Galen  (a.  d.  131-201)  knew  of  its 
power,  which  he  compared  to  the  magnetic  effect  of  a  lodestone ;  - 
he  noted  that  it  produced  numbness  or  anaesthesia  of  parts  that 

^  The  Historie  of  the  World,  commonly  called,  the  Xafurall  Historic  of  C.  Plinius 
Secundus,  Translated  into  English  by  Philemon  Holland  Doctor  in  Physicke,  2  vols., 
London,  1601.    The  quotation  is  from  book  ix,  cliapter  42,  of  Holland's  notation. 

2  Galen.  De  locis  affectis,  Lib.  vi.    Kiihn  viii.  421. 

2391  £ 


-jO  CiKKlvK    BI()L()(JV    AM)   ITS    IIELATIOX   TO 

it  touched  '  and  ho  thcrctoro  rccoinmcndcHl  the  appHcation  of  the 
living  fish  to  tlie  liead  for  lieadache.-  Simihir  reineches  are  referred 
to  by  Scribonius  Largiis  (a.  d.  47),  Marcellus  Empiricus  of  Bor- 
deaux (fifth  century),  and  Aetius  of  Amida  (sixth  century). 

The  Torpedo  and  its  powers  have  been  known  continuously 
from  Greek  times,  but  many  centuries  went  by  without  any  eluci- 
dation of  its  structure.  The  first  to  suggest  the  true  nature  of  the 
shock  of  electric  fish  was  Muschenbroeck  in  1762,  who  compared 
their  shocks  to  those  of  a  Leyden  jar.^  A  series  of  exjjeriments 
on  the  Torpedo  was  undertaken  by  Walsh  in  1772,^  and  by 
Ingenhousz  in  1775,^  and  about  the  same  time  the  structure  of 
the  electric  organ  was  described  by  John  Hunter.*  The  special 
electric  lobe  of  the  brain  and  its  homologies  and  those  of  the 
nerves  that  arose  from  it  were  not  completely  elucidated  until  the 
work  of  Letheby  in  1843.' 

ii.  Bees 

Aristotle's  account  of  bees  is  remarkable  for  its  extent.  He 
has  given  more  attention  to  these  than  to  any  other  group  of 
insects.  Yet  it  must  be  confessed  that  although  his  account  con- 
tains many  accurate  and  striking  observations,  it  also  contains 
numerous  errors  and  is  obviously  largely  drawn  from  hearsay  and 
from  secondhand  accounts.  We  have  omitted  many  erroneous 
elements,  and  have  put  together  some  of  his  best  passages  on  these 
insects. 

Of  the  structure  of  the  bee  Aristotle  tells  us  very  Httle,  nor 
does  that  little  contain  any  evidence  of  close  observance  of  the 
actual  parts.  We  read  that  '  some  insects  have  the  part  which 
serves  as  tongue  inside  the  mouth  as  with  ants  .  .  .  while  in  others 

1  Galen,  De  locis  affectis,  Lib.  ii,  Kiihn  viii.  72,  and  De  symptomatum  causis, 
Lib.  i,  cap.  5,  Kiihn,  vii.  109. 

2  Galen,  De  simplicium  medicamentorum  tempemmentis  ac  facultatibus,  Lib.  xi, 
cap.  11,  Kiihn,  xii.  365. 

^  Pieter  van  Muschenbroeck,  Introductio  ad  philosophiam  naturalem,  Leyden, 
1762. 

•*  J.  Walsh,  ■  On  the  Electric  Property  of  the  Torpedo', Philosophical  Transac- 
tions, London,  1772. 

5  J.  Ingenhousz,  '  Experiments  on  the  Torpedo  ',  Philosophical  Transactions, 
London,  1775. 

^  John  Hunter,  "  Anatomical  Observations  on  the  Torpedo ',  Philosophical 
Transactions,  July  1,  1773. 

'  H.  Letheby,  "  An  account  of  a  second  Gi/mnotus  Electricus,  together  with 
a  description  of  the  electrical  phenomena  and  the  anatomy  of  the  Torpedo ', 
Proceedings  of  the  London  Electrical  Society  Jor  1843,  p.  512,  London,  1843. 


>!; 


£   c  ^  c 
S  J  2x 


P    S 


*"     •-'     ^      c; 


THE   RISE  OF  MODERN  BIOLOGY  51 

it  is  placed  externally.  In  this  latter  case  it  resembles  a  sting, 
and  is  hollow  and  spongy,  so  as  to  serve  at  one  and  the  same  time 
for  tasting  and  for  the  taking  up  of  nutriment.  This  is  plainly  to 
be  seen  in  flies  and  bees.'  ^  Thus  in  these  animals,  as  he  tells  us, 
the  j)roboscis  protrudes  from  the  mouth,^  and  he  generaUzed 
correctly  that  in  insects  the  mouth  parts  are  either  biting  or 
sucking.  Beyond  this  stage  Western  biology  hardly  advanced 
until  the  time  of  Mouffet  (1553-1604),  who  prepared  beautiful  and 
accurate  paintings  of  a  large  number  of  insects.  Unfortunately 
his  best  figures  of  bees  have  greatly  deteriorated.  We  reproduce, 
however,  his  drawing  of  the  hornet  (Plate  lv).^  Definite  improve- 
ment of  Mouffet's  work  was  made  by  the  members  of  the  first 
Academy  of  the  Lynx,  a  small  body  that  came  into  existence  in 
1603  and  fell  to  pieces  with  the  death  of  their  president,  Federigo 
Cesi,  in  1628.  For  the  researches  of  the  Academy  the  microscope  was 
used,  and  as  the  instrument  was  hardly  available  until  1611  (vide 
Article  No.  10  of  this  volume),  the  period  during  which  their  micro- 
scopic work  was  done  is  further  narrow ed."*  The  figure  that  we 
reproduce  is  the  earliest  drawing  known  for  which  the  microscope 
was  certainly  used  (Fig.  25).    It  was  probably  made  about  1625. 

Aristotle's  description  of  the  habits  of  bees  is  much  more 
entertaining  and  complete  than  his  account  of  the  structure  of 
these  creatures.  It  is  impossible,  however,  to  give  more  than 
a  fraction  of  what  he  has  to  say  on  the  subject. 

'  There  are  nine  varieties  [of  bee-like  creatures]  of  which  six  are 
gregarious — the  bee,  the  king-bee,  the  drone-bee,  the  annual  wasp, 
.  .  .  the  anthrene  [or  hornet],  and  the  tenthredo  [or  ground- wasp] ; 
three  are  solitary — the  smaller  siren,  of  a  dun  colour,  the  larger 
siren,  black  and  speckled,  and  the  third,  the  largest  of  all,  that 
is  called  the  humble-bee.^  .  .  .  The  httle  bees  are  more  industrious 
than  the  big  ones  :  their  wings  are  battered  ;  their  colour  is 
black,  and  they  have  a  burnt-up  aspect.  Gaudy  and  showy  bees, 
like  gaudy  and  showy  women,  are  good  for  nothing.'  ^ 

^  De  parfibus  animalium,  ii.  17  ;  661'^  15. 

-  De  partibus  animalium,  iv.  5  ;  678''  15. 

^  The  figures  in  the  printed  work  of  Mouffet  are  much  inferior  to  the  drawings 
in  his  IMS.  See  his  Insectorum  sive  minimorum  animalium  Theafrum,  London, 
1634,  English  translation  in  E.  Topsell's  History  of  four-footed  beasts  and  serpents, 
London,  1658,  and  compare  with  Brit.  Mus.  MS.  Sloane  4014  (Plate  lv). 

^  Early  microscopes  and  microscopic  observations  are  described  in  two  papers 
by  Charles  Singer,  '  Notes  on  the  Early  History  of  Microscopy,'  Proc.  Ro;/.  Soc. 
of  Med.,  London,  1914,  vol.  vii  (sect,  of  Hist,  of  Med.),  p.  247,  and  'The  Dawn  of 
Microscopical  Discovery,'  Journal  Roy.  Microscopical  Soc,  London,  1915,  p.  317. 

5  Historia  animalium,  ix.  39  ;  623''  7.        ^  Historin  animalium,  ix.  40  ;  627-'  12. 

E  2 


f>2  GREEK    BIOLOGY 

'  Ants  never  «i,()  a-lmntii»g,  hut  gatlicr  iij)  what  is  ready  to 
hand  ;  tlie  .sj)i(U'r  makes  notliing,  and  hiys  up  no  store,  hut  simply 
L^oes  a-iiunting  for  its  food  ;  while  the  hee  .  .  .  does  not  go  a-hunting, 
hut  constructs  its  food  out  of  gathered  material  and  stores  it  away, 
for  honey  is  the  hee's  food.  .  .  .  They  have  also  another  food 
which  is  called  hee-bread  ;  this  is  scarcer  than  honey  and  has  a  sweet, 
fig-like  taste ;   this  they  carry,  as  they  do  the  wax,  on  their  legs. 

'  \'ery  remarkable  diversity  is  observed  in  their  methods  of 
working  and  their  general  habits.  When  the  hive  has  been 
delivered  to  them  clean  and  em})ty,  they  build  their  waxen  cells, 
bringing  in  the  juice  of  all  kinds  of  flowers  and  the  "  tears  "  or 
exuding  sap  of  trees.  .  .  .  With  this  material  they  besmear  the 
ground-work,  to  provide  against  attacks  of  other  creatures  ;  .  .  .  they 
also  with  the  same  material  narrow  by  side-building  the  entrances 
to  the  hive  if  they  are  too  wide.  .  .  .  They  begin  building  the 
combs  downwards  from  the  top  of  the  hive,  and  go  down  and 
down  building  many  combs  connected  together  until  they  reach 
the  bottom.  The  cells,  both  those  for  the  honey  and  those  also 
for  the  grubs,  are  double-doored  ;  for  two  cells  are  ranged  about 
a  single  base,  one  pointing  one  way  and  one  the  other,  after  the 
manner  of  a  double  goblet.  The  cells  that  lie  at  the  commencement 
of  the  combs  and  are  attached  to  the  hives,  to  the  extent  of  two  or 
three  concentric  circular  rows,  are  small  and  devoid  of  honey ;  the 
cells  that  are  well  filled  with  honey  are  most  thoroughly  luted  with 
wax.^  The  ordinary  bee  is  generated  in  the  cells  of  the  comb,  but  the 
ruler-bee  in  cells  down  below  attached  to  the  comb,  suspended  from 
it,  apart  from  the  rest,  six  or  seven  in  number,  and  growing  in  a  way 
quite  different  from  the  mode  of  growth  of  the  ordinary  brood. ^ 

'  The  drones,  as  a  rule,  keep  inside  the  hive ;  when  they  go  out 
of  doors,  they  soar  up  in  the  air  in  a  stream,  whirHng  round  and 
round  in  a  kind  of  gymnastic  exercise :  when  this  is  over,  they  come 
inside  the  hive  and  feed  to  repletion  ravenously.^ . .  .  The  kings  are 
never  themselves  seen  outside  the  hive  except  with  a  swarm  in 
fhght :  during  which  time  all  the  other  bees  cluster  around  them.^ 
.  .  .  These  rulers  have  the  abdomen  or  part  below  the  waist  half  as 
large  again,  and  they  are  called  by  some  the  "  mothers  "  from  an  idea 
that  they  bear  or  generate  the  bees ;  and,  as  a  proof  of  this  theory 
of  their  motherhood,  they  declare  that  the  brood  of  the  drones 
appears  even  when  there  is  no  ruler-bee  in  the  hive,  but  that  the 
bees  do  not  appear  in  his  absence.  Others,  again,  assert  that  these 
insects  copulate,  and  the  drones  are  male  and  the  bees  female.^ 

'  Bees  scramble  up  the  stalks  of  flowers  and  rapidly  gather 
the  beeswax  with  their  front  legs  ;  the  front  legs  wipe  it  off  on 
to  the  middle  legs,  and  these  pass  it  on  to  the  hollow  curves  of 
the  hind  legs  ;  when  thus  laden,  they  fly  away  home,  and  one 
may  see  plainly  that  their  load  is  a  heavy  one.    On  each  expedition 

1  Historia  animalium,  ix.  39  ;  623^  13.  ^  Historia  animalium,  v.  22  ;  553'^  2. 
3  Historia  animalium,  ix.  40 ;  624^  22.  ^  Historia  animulium,  ix.  40 ;  625**  7. 
5  Historia  animalium,  v.  21  ;  553^27. 


iApe  inatto  Ji  caihinare, 

z  y4pe  jum'no 

3  yipe  chemojfra  ilji'anco 

4,     Cof-no 

S   'PcnneaeH'ylpe 

C-  CkrAio  tufto  prior 0 


•YTc/tafdtuttelcJueparn\  lo  Mulecouero Spina 
%  TefSlconialm^uarijjieX  //■  gamha.chemoJti-ala. 
aata  uerso  laao/a         \  parte  ittteriot^ 


<^    ^tnauc  conic  sue 
^  linguectt,  o^uame 
chc  I'  ahlracci'ano 


\i  i    gamSa  dalJa  handcL^ 
esTrriore  ■ 


Fig.  25.     ENLARGED    FIGURES     OF    THE    BEE 
From  Francesco  Stelluti's  Perdo  tradotto,  Rome,  1630,  The  plate  is  the  product  of  the  Accademia 
dei  Lincei.    It  was  based  on  the  work  of  Cesi  (d.  1628),  drawn  by  Fontana  (probably  about 
1625),  and  contains  observations  by  Johannes  Faber  and  Francesco  Stelluti.      It  is  probably 
the  earliest  printed  figure  drawn  with  the  aid  of  the  microscope. 


E  3 


64  (JRKIOK    lilOLOdV   A\I)    ITS    III<:LAT10N   TO 

tlic  Ix'c  (Iocs  not  lly  Irom  a  llowci"  of  oik-  kind  to  a  (lower  of  ajiotlw^r, 
but  Hies  from  one  violet,  say,  to  another  violet,  and  riev(5r  meddles 
with  anotluM-  liowci-  until  it  has  got  hack  to  the  hive  ;  on  reaching  the 
hive  th(\v  throw  oil'  their  load,  and  cacii  bee  on  his  return  is  acconi- 
|)anied  by  three  or  four  companions.  One  cainiot  wc^ll  toll  what  is 
the  substance  they  gather  nor  the  exa(;t  j)rocess  of  their  work..'  .  .  . 
Bees  feed  on  thyme  :  and  the  white  thyme  is  better  than  the  red." 
.  .  .  Bees  seem  to  take  a  |)leasure  in  listening  to  a  rattling  noise  : 
and  eonse(iuently  men  say  that  they  can  muster  them  into  a  hive  by 
rattling  with  crockery  or  stones.'  .  .  .  Whenever  the  working-bees 
kill  an  enemy  they  try  to  do  so  out  of  doors.*  Bees  that  di(;  are 
removed  from  the  hive,  and  in  every  way  the  creature  is  remarkable 
for  its  ek'anly  habits  ;  in  ))oint  of  fact,  they  often  fly  away  to  a  dis- 
tance to  \oid  their  excrement  because  it  is  malodorous  ;  and,  as  has 
been  said,  they  are  annoyed  by  all  bad  smells  and  by  the  scerit  of 
perfumes,  so  much  so  that  they  sting  peoy)le  that  use  perfumes." 

'  When  the  flight  of  a  swarm  is  imminent,  a  monotonous  and 
quite  peculiar  sound  made  by  all  the  bees  is  heard  for  several 
days,  and  for  two  or  three  days  in  advance  a  few  bees  are  seen 
flying  round  the  hive  ;  it  has  never  as  yet  been  ascertained,  owing 
to  the  difficulty  of  the  observation,  whether  or  no  the  king  is 
among  these.  When  they  have  swarmed,  they  fl}-  away  and 
separate  off  to  each  of  the  kings  ;  if  a  small  swarm  happens  to 
settle  near  to  a  large  one,  it  will  shift  to  join  this  large  one,  and 
if  the  king  \^'liom  they  have  abandoned  follows  them,  they  put 
him  to  death.  So  much  for  the  quitting  of  the  hive  and  the 
swarm-flight.  Separate  detachments  of  bees  are  told  off  for 
diverse  operations  ;  that  is,  some  carr}^  flower-produce,  others 
carry  water,  others  smooth  and  arrange  the  combs.  A  bee  carries 
water  when  it  is  rearing  grubs.  No  bee  ever  settles  on  the  flesh 
of  any  creature,  or  ever  eats  animal  food.  .  .  .  When  the  grubs 
are  grown,  the  bees  put  food  beside  them  and  cover  them  with 
a  coating  of  wax  ;  and,  as  soon  as  the  grub  is  strong  enough,  he 
of  his  own  accord  breaks  the  lid  and.  comes  out.  .  .  . 

'  When  the  bee-masters  take  out  the  combs,  they  leave  enough 
food  behind  for  winter  use  ;  if  it  be  sufficient  in  quantity,  the 
occupants  of  the  hive  will  survive  ;  if  it  be  insufficient,  then,  if 
the  weather  be  rough,  they  die  on  the  si:>ot,  but  if  it  be  fair,  they 
fly  away  and  desert  the  hive.  Away  from  the  hive  they  attack 
neither  their  own  species  nor  any  other  creature,  but  in  the  close 
proximity'  of  the  hive  they  kill  whatever  they  get  hold  of.  Bees 
that  sting  die  from  their  inability  to  extract  the  sting  without  at 
the  same  time  extracting  their  intestines.  True,  they  often  recover, 
if  the  person  stung  takes  the  trouble  to  press  the  sting  out ;  but 
once  it  loses  its  sting  the  bee  must  die.*^ 

The  diseases  that  chiefly  attack  prosperous  hives  are  (a)  first  of 

1  Hisioria  animalium,  ix.  40  ;  624=*  35.  "  Historia  animalium,  ix.  40 ;  626^  20. 
"  Historia  animalium,  ix.  40 ;  626^  15.  *  Historia  animalium,  ix.  40 ;  625=*  31 . 
*  Historia  animalium.  ix.  40  ;  626^  23.        ^  Historia  animalium.  ix.  40  ;  625'^'  6. 


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THE  RISE  OF  MODERN  BIOLOGY  55 

all  the  clerus — this  consists  in  a  growth  of  little  worms  on  tlie  floor, 
from  which,  as  they  develop,  a  kind  of  cobweb  grows  over  the  entire 
hive,  and  the  combs  decay.  ^  .  .  .  Bees  brood  over  the  combs  and  so 
mature  them ;  if  they  fail  to  do  so,  tlie  combs  are  said  to  go  bad 
and  to  get  covered  with  a  sort  of  sj)ider's  web.  .  .  .  When  the 
combs  keep  settling  down,  the  bees  restore  the  level  surface,  and 
put  props  underneath  the  combs  to  give  themselves  free  passage- 
room  ;  for  if  such  free  passage  be  lacking  they  cannot  brood,  and 
the  cobwebs  come  on."  ...  (6)  There  is  another  insect  resembling 
the  moth,  called  by  some  the  pyraustes,  that  flies  about  a  lighted 
candle  :  this  creature  engenders  a  brood  full  of  fine  down.  It  is 
never  stung  by  a  bee,  and  can  only  be  got  out  of  a  hive  by  fumiga- 
tion, (c)  A  caterpillar  also  is  engendered  in  hives,  of  a  species  nick- 
named the  teredo,  or  "  borer  ",  with  which  creature  the  bee  never 
interferes.^ .  .  .  {d)  Another  diseased  condition  is  indicated  in  a  lassi- 
tude on  the  part  of  the  bees  and  in  malodorousness  of  the  hive.'  * 

The  account  of  the  diseases  of  hives  described  by  Aristotle  is 
paraphrased  by  Pliny. ^  These  diseases  can  be  identified  with 
comparative  confidence. 

(a)  The  Clerus  is  held  to  be  the  Trichodes  apiarius,  a  red  and 
blue  beetle  which  is  known  to  destroy  the  larvae  of  the  honey  bee. 
When  honeycomb  is  destroyed  from  this  or  any  other  cause  a  mould 
is  liable  to  grow  upon  it.  It  is  possible  that  Aristotle  was  confusing 
this  growth  with  the  cocoons  described  under  the  next  heading.*^ 

(fe)  The  moths  that  inhabit  hives  are  Galleriidae,  a  small  group, 
many  of  which,  Galleria  mellonella  especially,  live  in  and  consume 
bee  hives.  The  spider's  web  described  above  is  probably,  in  part, 
the  cocoon  of  this  species. 

(c)  The  caterpillars  called  Teredo  are  the  larvae  of  species  of 
the  Galleriidae,  some  of  which  have  the  habit  of  spinning  their 
cocoons  into  a  mass  which  is  perhaps  described  by  Aristotle  as 
the  'cobweb  '  and  also  as  the  '  brood  full  of  fine  down  '. 

{d)  This  is  some  form  of  foul  brood,  a  condition  first  described 
in  modern  times  by  Schirach  in  1769,'  and  more  minutely  and 
carefully  in  the  island  of  Sjn^a  by  Delia  Rocca  ^  towards  the  end 
of  the  eighteenth  century.  The  actual  nature  of  the  disease — in 
the  causation  of  which  a  number  of  spore-bearing  organisms  are 

^  Hisioria  animalium,  ix.  40  ;  G2G''  1(3.  ^  Historia  animaliurn/ix.  40  ;  &2')'^('). 

^  Hisioria  animalium,  viii.  27  ;  605*^  12.        ■*  Hisioria  animalitnn,ixA() :  (>2<)''  18. 

5  Pliny,  xi.  20. 

^  C.  J.  Sundevall,  Die  Thierarten  des  Aristoteles.  Stockholm,  1863. 

'  A.  G.  Schirach,  Der  Sdchsische  Bienenmeister,  oder  kurze  Anweisung  fiir  den 
Landmann  zur  BienenzucJit,  nebst  beyyefiiytem  Bienenkalender,  Lobau,  1769. 

*  L'abbe  Delia  Kocca,  Traite  complet  sur  les  Abeilles  avec  une  methode  nouvelle 
de  les  gouverner,  telle  qitelle  se  pratique  a  Syra,  Paris,  2  vols.,  1790. 


66  (;i(KKK    lil()L()(;Y   AND    I'l'S    II  KI.A'I'IOX   TO 

involved-  lias  hccii   more  fully  cleared   up  only  iu  (juitc  modern 
times,  be^iiniin^  with  tlie  work  of  F<M(liiiand  Colin  (IH2S-98). 

Despite^  the  figures  of  Mouffet  pnjpared  Iat(^  in  the  sixte-entli 
century,'  and  of  the  Academy  of  the  J^ynx  early  in  the  seven- 
teenth," the  knowledge  of  tlie  various  forms  of  bee  advanced  but 
slowly.  The  male,  female,  and  neuter  were  not  adequately  dis- 
tinguished for  what  they  were  until  the  work  of  Go(^dart  and 
de  Mey  in  1G()2.'  The  knowledge  of  the  habits  of  these  creatures 
was  even  more  behindhand,  and  although  some  advance  was  made 
by  Charles  Butler  (died  1647)  in  1609,"  yet  Rusden  in  1689"^  was 
still  describing  the  queen  bee  as  a  king  in  the  language  of  Aristotle. 
The  whole  subject  had,  however,  by  that  time,  been  put  on  a  firmer 
basis  by  the  microscopical  researches  of  Swammerdam  (between 
1662  and  1675) «  and  Malpighi'  (about  1680).« 

V.    The  General  Course  of  Botanical  Knowledge 
(a)  Botany  among  the  Greeks 

The  history  of  Botany  is  more  fortunate  than  that  of  its 
companion  branch  of  Biology  in  that  the  material  exists  for  telhng 
it  as  an  almost  continuous  story.  Thus  for  the  observation  of 
plants  our  own  age  is  linked  with,  and  not  separated  from,  that 
of  the  Greeks.  Much  of  the  material,  especially  for  the  period 
from  the  sixth  to  the  twelfth  century,  is  difficult  of  access,  and 
this  we  have  sought  to  present  here  in  greater  detail  than  its 
quahty  would  otherwise  demand. 

Among  uncivilized  peoples  the  knowledge  of  plants  is  by  no 
means  confined  to  their  culinary  uses.  Even  the  most  primitive 
races  have  also  a  herb-lore  which  instructs  them  what  plants  to 
use  and  how  to  use  them  for  the  treatment  of  disease.  Much 
effort    has    been   expended    in   attempting   to    demonstrate   the 

1  British  Museum  MS.  Sloane  4014,  written  before  1589. 

2  Francesco  Stelluti,  Persia  tradotto,  Rome,  1630,  illustrates  this  work.  The 
more  important  Apiarium  of  Federigo  Cesi,  Rome,  1625,  is  excessively  rare,  and 
I  believe  there  is  no  copy  in  this  country. 

^  Jean  Goedart,  Metamorphosis  et  historia  naturalis  insectorum  cum  com- 
mentario  lohannis  de  Mey,  Middelburg  (1662-7). 

*  Charles  Butler,  The  Feminine  Monarchie  or  a  Treatise  concerning  Bees  and 
the  due  ordering  of  Bees.  Oxford,  1609. 

5  ]Moses  Rusden,  A  Further  Discovery  of  Bees,  London,  1689. 

^  Jan  Swammerdam,  Bybel  van  de  Natuur,  Leyden,  1737. 

'  Marcello  Malpighi,  Opera  Omnia,  London,  1686. 

8  A  useful  article  on  the  knowledge  of  bees  displayed  by  the  Aristotelian 
writinc  is  by  J.  Klek  and  L.  Armbruster,  '  Die  Bienenkunde  des  Aristoteles  und 
seiner  Zeit  ',  Archiv  fiir  Bienenkunde,  i,  Abt.  6,  Freiburg  im  Brci.sgau,  1919. 


THE   RISE  OF  MODERN  BIOLOGY  57 

therapeutic  value  of  such  drugs,  but  it  would  appear  that  folk 
herb-lore  is  no  more  rational  than  other  departments  of  folk 
medicine  and  the  majority  of  the  ingredients  of  all  pharma- 
copoeias, save  perhaps  the  most  modern,  are  in  fact  without 
appreciable  physiological  action  and  certainly  are  no  cures  for 
the  conditions  for  which  they  are  given. 

The  recipients  of  the  herb-lore  traditions  among  the  Greeks 
were  the  rhizotomists.  These,  as  a  class,  were  ignorant  men,  corre- 
sponding in  a  measure  to  our  herbalists,  and  they  occupied  them- 
selves with  gathering  herbs,  sometimes  for  the  use  of  the  physicians, 
sometimes  in  order  that  they  might  themselves  usurp  the  functions 
of  the  physicians.  They  were  superstitious  and  practised  a  complex 
ritual  in  obtaining  their  drugs.  Fragments  of  this  ritual  have 
survived,^  and  we  can  detect  in  it  ceremonies  still  closely  followed 
by  European  peasantry  engaged  in  similar  practices.  Rhizo- 
tomists were  often  of  evil  reputation,  and  Sophocles,  who  was 
contemporary  with  Hippocrates,  wrote  a  play,  now  lost,  entitled 
'  The  Rhizotomists ',  the  word  having  been  used  by  him  as  almost 
equivalent  to  poisonmongers.  The  profession  and  to  some  extent  the 
tradition  of  the  rhizotomists  extended  from  Greek  into  mediaeval 
and  even  modern  times,  and  they  and  their  work  are  not  infre- 
quently illustrated  in  the  manuscripts  (Fig.  26). 

We  learn  little  of  the  botanical  knowledge  of  the  sixth  and 
fifth  centuries  from  the  works  that  make  up  the  Hippocratic 
collection.  iVbout  three  hundred  plants  are  mentioned  as  of  value 
for  medicinal  purposes,  and  this  implies  considerable  botanical 
knowledge,  but  we  can  glean  almost  nothing  of  the  plants  them- 
selves from  the  Hippocratic  writings.  With  the  fourth  century 
botany  as  a  separate  study  comes  into  full  view,  and  there  is 
evidence  that  the  subject  may  have  been  systematically  studied 
at  the  Academy  even  before  it  was  taken  up  by  the  Lyceum. 
From  the  latter  we  possess  documents  of  first-class  importance  in 
the  works  of  Theophrastus,  the  so-called  '  father  of  botany ', 
whose  achievements  are  considered  in  greater  detail  below  (p.  79). 

But  Theophrastus  is  the  father  of  botany  only  in  the  sense 
that  he  is  the  first  botanist  whose  writings  have  come  down  to  us. 
There  is  nothing  primitive  about  his  work,  nothing  to  suggest 

^  e.  g.  in  Theophrastus,  Historia  plantarum,  ix.  8.  Other  instances  can  be 
found  in  Pliny  and  have  been  collected  by  J.  J.  Mooney  in  his  Hosidiu<^  (ietas 
Tmgeihj  '  Medea  ',  Birmingham,  1919.  Yet  further  material  from  both  Clrcok 
and  Latin  sources  may  be  culled  from  A.  Abt,  Die  Apologie  dea  Apulein'^  von 
Madaxra  und  die  antihe  Zauberei.  Giessen,  1908. 


58  (UtKKK    IUULlJ(i^ 

that  lio  is  treading  j)atlis  (hat  iioiio  have  tiod  hclorc  On  tho 
(•(mtiary  he  is  a  tijorougiily  sophisticated  wiitcr,  evidently  tlie 
|U()duet  of  generations  of  tliought  and  even  of  icsearch.  We 
know,  moreover,  that  his  work  was  preceded  by  a  treatise  on 
phints  by  Aristoth^  wliich  is  now  lost,  though  fragments  of  it  have 
periiaps  survived.'  But  the  writings  of  'rh(;o|)hrastus  are  s))ecially 
vahiable  as  presenting,  after  Hippocrates,  tlie  first  suljstantially 
complete  works  of  Greek  observational  science  extant.  Viewed  in 
relation  to  the  com])leteness  and  ordered  sequence  of  the  History 
of  Plants,  the  biological  works  of  Aristotle,  in  the  form  in  which 
they  have  reached  us,  seem  mere  disarranged  note-books.  Like 
the  works  of  Aristotle,  those  of  Theophrastus  are  scientific  com- 
positions ;  that  is  to  say,  they  are  written,  in  large  part  at  least, 
for  the  ])urpose  of  describing  nature  and  not  for  the  direct 
apphcability  of  such  knowledge  to  the  needs  and  amenities  of  life. 
In  this  respect  they  stand  almost  alone  among  Greek  botanical 
works,  for  the  rest  of  Greek  botanical  history  has  to  be  pieced 
together  mainly  from  poetical  and  pharmaceutical  \vritings. 

From  the  second  century  b.  c.  we  have  in  Greek  the  Alexiphar- 
maca  and  the  Theriaca  of  Nicander,  two  works  on  poisons  and  their 
antidotes  which  deal  with  a  number  of  plants  from  the  point  of 
view  of  their  special  topics  and  not  from  the  scientific  aspect. 
The  De  re  rustica  of  Cato  the  Censor  is  contemporary  with  these 
works  and  is  even  more  devoid  of  the  Greek  scientific  spirit.  For 
the  first  century  b.  c.  we  are  better  provided,  for  we  have  the 
literar}^  works  of  Virgil  and  the  agricultural  treatises  of  Varro 
and  Columella,  supplemented  by  what  can  be  gleaned  from  the 
valuable  medical  compendium  of  Celsus. 

The  first  century  of  the  Christian  era  is  richer  in  important 
botanical  works  than  any  period  from  the  fourth  century  b.  c. 
until  the  sixteenth  century.  In  Pliny's  Natural  History  Ave  have 
a  collection  of  current  views  on  the  nature,  origin,  uses,  and  treat- 
ment of  plants  such  as  we  might  expect  from  a  very  intelligent, 
industrious,  and  honest  member  of  the  landed  class  who  was 
devoid  of  critical  or  special  scientific  skill.  More  valuable  and 
ranking  second  only  to  Theophrastus  in  importance  is  the  treatise 

^  Put  together  by  F.  Wimmer,  Phytologiae  Aristoielkae  Fragmenta.  Breslau, 
1838  (unfinished).  The  spurious  De  Plantis  of  Aristotle  is  attributed  to  Nicholas 
of  Damascus  by  E.  H.  F.  Meyer,  Nicolai  Damasceni  de  plantis  .  .  .  Aristoteli 
vulgo  adscripti  ex  Isaaci  ben  Honaici  versione  Arahica  Latine  vertit  Aljredus, 
Leipzig,  1841.  It  probably  contains  elements  in  the  Ari.stotelian  tradition.  See 
note,  p.  13. 


Fig.  26.  This  drawing  is  traced  from  a  facsimile  on  Plate  xxii  of  the  Atlas  to  Piei-o 
Giacosa's  Magistri  Salernitaui,  Turin,  1901.  The  MS.  from  Avhich  (iiacosa's  facsimile 
was  taken  has  since  perished.  It  bore  the  arms  of  Savoy  and  was  work  of  the  fifteenth 
century.  '  The  figure  represents  herbalists  at  work  on  a  momitain,  the  slopes  of  which  arc 
covered  with  a  variety  of  plants.  One  of  the  herbalists  is  climbing  an  oak  tree  to  secure 
the  mistletoe  growing  on  it.  The  other  is  digging  up  plants  and  placing  them  in 
a  receptacle. 


fiO  (;|JKKK    lilOLOCV    AM)    IIS    UKLATlUX    TO 

on  Malcrid  M((lic(i  of  Dioscoridcs.  It  consists  of  a  scries  of  careful 
descriptions  of  plants,  and  of  their  uses  in  medicine,  arranged,  it 
is  true,  almost  without  leference  to  the  nature  of  the  plants 
themselves,  but  ((uite  invaluable  for  its  terse  and  striking  descrip- 
tions which  often  include  habits  and  habitats.  Its  history  has 
shown  it  to  be  the  most  inlluential  botanical  treatise  ever  penned. 

After  J)ioscorides  Greek  botany  declines.  The  moimmental 
intellect  of  Galen  in  the  second  century  of  the  Christian  era  hardly 
applied  itself  to  plants,  and  his  pharmacoi)oeia,  copious  though 
it  is,  gives  but  a  scant  glimpse  of  contem])orary  botany.  Such 
Greek  botanical  writers  as  followed  were  Httle  but  copiers  of  Galen 
and  Dioscorides,  and  the  history  of  Greek  botany  is  from  now  on 
a  stor}'^  of  the  continued  disintegration  of  knowledge. 

But,  retracing  our  steps,  there  yet  remains  for  consideration 
a  writer  of  the  first  century  b.  c.  the  full  importance  of  whom 
has  only  recently  been  reahzed.  There  is  evidence  that  Crateuas, 
the  most  intelligent  and  instructed  of  the  rhizotomists  who  lived 
during  this  century,  occupied  himself  not  onl}^  in  collecting  but 
also  in  drawing  plants.  He  is  thus  the  father  of  the  very  important 
botanical  department  of  plant  illustration.^  Crateuas  was  the 
attendant  of  JVIithridates  VI  Eupator,  but  was  also  an  author, 
and  though  his  works  have  perished,  fragments  have  survived  in 
a  Vienna  codex.-  This  manuscript,  to  which  the  name  of  Juha 
Anicia  is  attached,  was  prepared  in  Constantinople  a  httle  before 
the  year  512  as  a  wedding  gift  to  that  lady,  the  daughter  of 
Flavins  Anicius  Olybrius,  Emperor  of  the  West,  and  it  is  not 
improbable  that  many  of  the  figures  in  it  are  copies  of  Crateuas' s 
own  drawings  or  of  pictures  prepared  under  his  supervision  in 
the  first  century  b.  c.  He  is  perhaps  represented  at  work  in  one 
of  the  more  damaged  miniatures  of  this  great  manuscript  (Fig.  27), 
and  \ve  have  what  are  perhaps  portraits  of  Dioscorides  himself  in 
this  and  other  miniatures  of  the  same  volume  (Fig.  28).^ 

1  Pliny,  Hist.  Xat.  xxv.  4. 

2  Max  \yellmann,  '  Krateuas  ',  Abh.  der  kgl.  Gesellschaft  der  Wissenschaften 
zu  Gottingen,  philologisch-historische  Abt.,  Neue  Folge,  Bd.  ii,  No.  1,  Berlin,  1897  ; 
and  M.  Wellmann,  '  Das  alteste  Krauterbuch  der  Griechen  ',  in  Festgabe  fiir 
Franz  Susemihl,  Leipzig,  1898. 

3  These  miniatures  are  represented  in  their  damaged  state  in  Rendel  Harris, 
The  Ascent  of  Olympus,  Manchester,  1917.  The  entire  MS.  has  been  reproduced 
in  two  luxurious  but  excessively  inconvenient  elephant  folios  by  J.  de  Karabacek, 
Leyden,  1906.  The  original  work  has  been  removed  from  Vienna  to  St.  Mark's 
Librarv  at  Venice. 


THE   RISE  OF  MODERN  BIOLOGY 


61 


Thus  even  before  the  Juha  Anicia  MS.,  botanical  illustration 
had  had  a  long  history,  and  surviving  fragments  of  a  herbal  on 
papyrus  of  the  second  century  ^  show  that  a  strong  tendency  to 
diagrammatize  the  forms  of  plants  had  already  set  in  among  the 


Fig.  27,     Restored  from  the  Julia  Anicia  MS.,  fo.  5  v.  about  a.d.  512.     Dioscorides  writes 
while  Intelligence  ('ETriVoin)  holds  the  mandrake  for  the  artist,  Crateuas  (?),  to  copy.^^ 

Greeks.  But  the  tradition  represented  by  the  Julia  Anicia  MS. 
was  that  which  for  many  centuries  largely~controlled  the  whole 
art  of  plant  illustration  in  Greek-speaking  lands.  The  history  of 
this  manuscript  is  thus  itself  the  history  of  an  important  line  of 
botanical  knowledge  during  the  Middle  Ages.  The  Julia  Anicia 
MS.  is  not  exactly  a  text  of  Dioscorides  but  is  a  composite  docu- 

^  J.  de  M.  Johnson,  '  A  botanical  Papyrus  with  Illustrations  '  in  the  Archiv 
f.  Gesch.  d.  Natunvissenschajfen  und  der  Technik,  iv,  p.  403,  Leipzig,  1913. 


62 


(IIJKKK    RIOLOCV    AND    IIS    KKLATION    TO 


ment  of  wliicli  llic  iia(  me  imd  orij^iii  is  ^(^|l^(•s(■llt(•(l  in  tlic  (lia<^raTn 
opposite  (Fi^,^  2J)). 

I^]\('M  ill  \\w  sovonth  cent  my  the  sources  of  the  Julia  Anicia 
figures  were  still  bcini^  iinitatcd  with  considerable  accuracy  and 


Z^^IOCKOpl^HC 


tV  Pt  CIC 


Fig.  28.  Restored  from  the  Julia  Anicia  MS.,  fo.  4  v.  about  a.d.  .512.  Discovery  (Kvpeais) 
presents  a  mandrake  to  the  physician  Dioscorides.  The  mandrake  is  still  tethered  to  the 
hoimd  whose  life  is  sacrificed  to  obtam  it. 

skill/  but  as  the  centuries  went  by  and  the  figures  Avere  copied  and 
recopied  without  reference  to  the  original  they  moved  further  and 
further  from  the  facts  until  at  last  they  remained  as  mere  diagrams. 
By  this  time  the  gift  of  naturalistic  representation  had  left  the 
Greeks,  but  traces  of  some  power  to  imitate  classical  models  of 

^  As  in  the  so-called  Codex  Neapolitanus  of  the  seventh  century  at  St.  Mark's, 
Venice,  A  facsimile  of  a  page  of  this  work  has  been  reproduced  by  the  New 
Palaeographical  Society,  ii,  Plate  45.  Copies  of  the  Julia  Anicia  itself,  of  which 
several  exist,  are  much  later,  e.  g.  that  described  by  0.  Penzig  in  his  Contribuzione 
aUa  storia  delta  Botanica,  Genoa,  1904.  There  is  a  similar  copy  in  the  University 
Library  at  Cambridge.    Press  Mark  Ee.  5.  7  (Browne  1385). 


THE   RISE   OF  MODERN   BIOLOGY 


63 


plant  paintings  may  still  be  traced  in  a  fragment  of  a  herbal  of 
the  eightli  century  discovered  in  the  cover  of  an  Armenian  book  ^ 
(Fig.  30),  in  the  famous  eighth-century  Vatican  MS.  of  Cosmas 
Indicopleustes,-  in  a  very  peculiar  little  manuscript  of  Nicander 
of  the  ninth  century''  (Plate  ix),  in  the  Paris  and  Cheltenham 
looBC 

Herbarium  of 
Cratevas  witn 


100  AD, 


A  seconci  illusLratec] 
Herbarium  ty  an 
unknov/n  author 


Pampliilus      Bioscorides 
De  Plantis       Materia  Medlca 


200AD. 


Galen's  De 

lacultatibiis 

mea-icameTitorum 


descriptions  Figures  taken 

drawn  from  from  unknowoi 

unknown  authors       sourras 


300  AB 


A  composite 

illustrated 

HerDarmm 


400  AD.. 


A  lexicon  of 
plant  synonyms 


Herb; 


armm   Uioscondis 


500  AD. 


-Jxjlia  Anicia  MS. . 


600  A.D . 

Fig.  29.     THE  GENEALOGY  OF  THE  EARLIEST  MANUSCRIPT  OF  DIO&CORIDES 

Dioscorides  MSS.  of  the  ninth  and  tenth  centuries  respectively 
(Plates  X  and  xviii),  in  the  Smyrna  Physiologus  of  the  eleventh 
century/  and  in  many  other  works  of  Byzantine  origin.  For  the 
rest,  however,  the  story  of  botany  is  mainly  in  the  West  and  not 
in  the  East.'^ 

^  Discovered  by  F.  C.  Conybeare.     Facsimile  in  MS.  Bodley  E.  19  (31528). 

2  Vat.  Gr.  699.    Reproduced  in  facsimile  by  Cr  Stornajolo,  Rome,  1909. 

^  Bibl.  nat.,  Supplement  grec,  247. 

*  Josef  Strzygowski,  '  Der  Bilderkreis  des  griechischen  Physiologus ',  in  the 
Byzantinisches  Archiv,  Heft  2,  Leipzig,  1899. 

^  We  do  not  here  touch  on  the  very  interesting  grouji  of  Dioscorides  herbals 
of  Persian  origin,  which  are  known  from  the  twelfth  centurj^  onw ards.  Chinese 
herbals  are  also  known. 


\ 


64       (;kkkk  bi()i.()(;v  and  its  iiklatjon  to 

A  ft'w  word.s  may  Ix'  devoted  to  tlie  (irecU  text  and  manu- 
scripts of  Dioscoiidcs.  Moditicatioii  and  interpolation  set  in  early 
and  on  an  extensive  scale.  This  process  was  encouraged  by  the 
alphabetical  rearrangement  of  the  paragra))hs  according  to  the 
name  of  the  drug  the  jnopcrtics  of  which  are  described.  Such 
a  rearrangement  was  made  in  the  fourth,  or  ])erlia})s  in  the  third 
century.  The  oldest  codices  are  of  this  tyyje,  and  are  thus  of 
comparatively  little  textual  value,  though  the  illustrations  that 
adorn  them  have  the  highest  interest,  alike  for  the  History  of 
Botany  and  of  Art.  On  the  other  hand  the  non-alphabetical 
manuscripts  are  less  ancient  and,  on  the  whole,  less  beautifully 
illustrated,  but  some  of  them  are  of  high  textual  imy)ortance. 

Alphabetical  Greek  Codices  of  Dioscorides 
The  alphabetical  Greek  codices  fall  naturally  into  three  classes : 

I.  This  class  contains  the  two  most  ancient  manuscripts.  Both 
are  elaborately  illustrated,  text  and  figures  being  derived  from 
one  common  archetype  of  the  fourth  century.  The  text  is  alpha- 
betically arranged  from  beginning  to  end.  It  draws  on  the 
Materia  Medica  alone  among  the  w^orks  of  Dioscorides,  but  also 
contains  certain  works  of  other  authors  (as  shown  in  Fig.  29). 
The  figures  illustrating  the  text  of  these  manuscripts  preserve 
the  tradition  of  Crateuas.    This  class  includes  only  : 

(a)  The  Ji^Zta^mcia,writtenincapitals  before 512,  and  known 
as  the  Constantinopolitaiius.  This  manuscript  was  formerly 
at  the  Vienna  Hofbibliothek,  where  it  was  numbered  Med.  Gr.  I. 
It  is  now  in  St.  Mark's  Library  at  Venice  (Plates  vi  and  vii). 
The  MS.  is  accessible  in  a  beautiful  photographic  facsimile. 

(6)  The  so-called  Neopolitanus,  written  in  half  uncials  in  the 
seventh  century.  This  manuscript  was  also  formerly  at  the 
Vienna  Hofbibliothek,  where  it  was  numbered  Suppl.  Gr.  28. 
It  is  also  now  in  St.  Mark's  Library  at  Venice.^ 

II.  This  class  contains  a  text  borrowed  not  only  from  the 
Materia  Medica,  but  also  from  the  other  Avorks  of  Dioscorides. 
The  text  is  divided,  according  to  the  subject,  into  five  sections  or 
books,  wdthin  each  of  Ayhich  the  order  is  alphabetical.  These 
sections  treat  respectively  of  (1)  plants,  (2)  animals,  (3)  oils, 
(4)  trees,  (5)  wines  and  stones.     In  (c)  and  (d)  the  text  is  com- 

1  There  is  an  excellent  but  antiquated  article  on  the  Constantinc/politamLS  by 
L.  Choulant  '  Ueber  die  HSS.  des  Dioscorides  mit  Abbildungen  ',  Archiv  fur  die 
zeichnenden  Kiin^te,  I,  p.  56,  Leipzig,  1855.  In  R.  Dodoens'  posthumous  Stirpium 
Historiae  Pemptades  sex,  Antwerp,  1616,  figures  on  pp.  123, 126, 149, 288, 372,  377, 
439,  and  572  marked  e  cod.  Caesareo  are  taken  from  the  ConstantinopoUtanus. 


THE    RISE   OF   MODERN   BIOLOGY  65 

bined  with  certain  spurious  works  of  Nicander.  Tlie  figures,  like 
those  of  class  I,  preserve  the  tradition  of  Crateuas  with  certain 
weH  marked  differences.  There  is  evidence  that  they  spring  from 
an  archetype  of  not  later  than  the  fourth  century. 

(c)  Cheltenham,  Phillipps,  21975,  tenth  cent.,  now  in  the 
Pierpont  Morgan  Library,  New  York  (Plate  xviii). 

(d)  Mount  Athos,  Laura  Monastery,  twelfth  cent. 

(e)  Venice,   St.   Mark's   Library,   No.   92.      Cotton   paper, 
thirteenth  cent. 

(/)  Escurial  l.T.  17.    Paper,  fifteenth  cent. 
III.    This  class  contains  only  the  Materia  Medica  of  Dioscorides 


Fig.  30.  '  Chamaepitys ',  from  a  fragment  of  an  eighth -century  Greek  Herbarium  [Bodl.  E.  19]. 
The  plant  is  probably  Ajuga  reptans  Linn.,  the  Creeping  Bugle,  or  some  allied  species. 

and  has  an  alphabetical  text  not  divided  into  books.     No  manu- 
script of  this  class  is  earlier  than  the  fourteenth  century. 
(g)  Milan,  Ambros.  A95  Sup.,  fourteenth  cent. 
(h)  Rome,  Vatican  Urbinas  66,  fifteenth  cent, 
(ji')   Venice,  St.  Mark's  272,  fifteenth  cent. 
(k)  Venice,  St.  Mark's  597,  fifteenth  cent, 
and  certain  sixteenth-century  manuscripts  at   Berlin,  Paris, 
and  the  Escurial. 

N 071- Alphabetical  Greek  Codices  of  Dioscorides 
The  subject-matter  of  the  remaining  manuscripts  of  Dioscorides 
is  not  in  alphabetical  order.  These  manuscripts  are  very  numerous 
and  we  need  only  mention  the  more  interesting.  They  fall  into 
two  classes,  of  which  the  first  is  the  more  important  for  fixing  the 
text  as  it  contains  only  the  genuine  work  of  Dioscorides.  In  tlie 
second  class  this  text  is  mingled  with  other  material. 

I.   Manuscripts  containing  only  works  of  Dioscorides.    Among 
the  most  important  are  the  following  : 

(/)  Paris  Bibl.  nat.  MS.  gr.  2179,  ninth  century  (Plate  x). 


fm       (iiMOiiK   lil()l.()(;^'  and  ris  iiklatiox  to 

Tliis  is  the   most    sahiahlc  oi   all   tlic   inaimscripts  for  fixiii<i 
the   text.       It    is   hcaiitifully  illustrated  aiui  it  i.s  interesting 
to  ohscive  tliat  the  figures  of  the  mandrake,  that  are  anthro- 
poinorplii*'  ill  all  the  otiier  nianii.seripts,  arc  not  here  given  any 
human  attributes.     Tims  these  figures  may  eontain  elements  in 
an  even  earlier  tradition  than  the  ('(rn.stantinoj)oiitanus  and 
NcopolHanus  and  may  take  us  back  beyond  the  foin-th  century 
and  |)(>rha|)s  beyond  Cratcuas.     'i'he  manuscript  is  badly  [)re- 
served  and  partially  illegi})le,  but  is  su|)j)lemente(l  by 
(///)   Wnice,  St.  Mark's  27li,  twelfth  century,  and 
[n)   Florence,  Laurentian  Pint.  74,  17,  twelftli  century. 
(///)  and  {h)  are  parts  of  one  manuscript  copied  from  {I)  or 
from  a  closely  similar  manuscri])t. 

(o)  Escurial  HI,  R  3,  imperfect,  eleventh  cent. 
[p)  Florence,  Laurentian  Pint.  74,  23.      The  only  perfect 
manuscript  of  this  class,  fourteenth  cent. 

[q)   Rome,  Vatican  Pal.  77.    The  older  leaves  of  this  manu- 
script rey)resent  the  same  tradition  as  (o),  fourteenth  cent. 
II.     The  Greek  manuscripts  of  Dioscorides  that  contain  other 
works  besides  his  are  very  numerous,  but  of  little  importance  for  the 
text.    A  few,  however,  have  interesting  figures.    Among  these  are : 
{r)  Paris,  Bibl.  nat.,  MS.  gr.  2180,  fifteenth  cent. 
{s)  Paris,  Bibl.  nat.,  MS.  gr.  2182,  ^vTitten  1481. 
The  relation  of  the  tradition  of  the  figures  to  that  of  the  text 
has  not  been  investigated.     It  is  a  subject  for  a  special  research, 
and  would  be  of  great  importance  for  the  history  of  Art.     From 
a  first  examination  we  may  say  that  the  line  of  descent  of  the 
figures  may  be  traced  as  far  as  the  thirteenth  century  along  lines 
parallel  to  those  of  the  text.^ 

To  sum  up  the  history  of  Greek  botany,  v/e  may  say  that  it 
probably  arose  ^\'ith  other  sciences  in  the  sixth  century  B.C.,  but 
that  it  does  not  come  into  clear  view  until  the  fourth  century  B.  c. 
It  was  then  firmly  established  as  a  scientific  discipUne,  botanic 
gardens  had  been  established,  much  research  had  been  made, 
lectures  were  being  given,  and  the  work  of  one  important  ^vriter 
has    survived.      By   the    first    century    b.  c.    scientific    botanical 

1  The  classification  of  the  manuscripts  given  above  is  largely  taken  from 
M.  Wellmann's  masterly  article  on  '  Dioskurides  '  in  Pauly-Wissowa's  Real- 
EncycJopddie  der  hlassischen  Altertumswissenschaft,  vol.  v,  Stuttgart,  1905.  Much 
information  may  also  be  obtained  from  H.  Diets'  '  Die  Handschriften  der  antiken 
Arzte.  II.  Teil.  Die  iibrigen  griechischen  Arzte  ausser  Hippokrates  und  Galenas ', 
in  the  Abluindlungen  der  konigl.  preuss.  Akademie  der  Wissenschaften,  Berlin,  1906. 


THE   RISE   OF   MODERN   BIOLOGY  67 

principles  had  been  absorbed  into  agriculture  and  medicine,  and 
their  appUcation  is  happily  illustrated  by  works  which  survive 
from  the  two  centuries  which  follow.  Tlien  begins  a  process  of 
decay,  but  as  late  as  the  seventh  century  a.  d.  very  careful  and 
accurately  illustrated  herbaria  were  still  being  prepared.  From 
then  on  only  decadent  imitations  are  known.  Some  of  these, 
however,  are  remarkably  accurate,  and  a  study  of  them  aids  us  in 
forming  an  idea  of  the  botanical  attainments  of  the  earlier  and 
the  limits  in  the  botanical  knowledge  of  the  later  centuries. 

(b)  Botany  in  the  West  from  the  sixth  to  the  twelfth  century 

{The  Dark  Ages) 
During  the  Dark  Ages,  and  even  until  the  twelfth  or  thirteenth 
century,  there  were  no  effective  additions  to  botanical  knowledge. 
Up  to  that  time  we  may  say  that  such  codified  botanical  knowledge 
as  existed  in  the  West  was  contained  in  a  very  small  group  of 
Latin  works  of  which  countless  manuscripts  existed.    The  versions 
of  these  works,  their  illustrations  and  their  general  appearance, 
present  remarkable  similarities  in  spite  of  their  wide  distribution. 
Three   of    them   especially   were   often   compounded   in   various 
proportions  to  form  a  single  text.    These  three  works  are  : 
(i)  The  Materia  Medica  of  Dioscorides. 
(ii)  The  Herbarium  of  '  Apuleius  '. 
(iii)  The  pseudo-Dioscoridean  De  Herbis  Femininis, 
(i)  The  work  of  Dioscorides  had  already  been  translated  into 
Latin  in  the  time  of  Cassiodorus  (490-585),  who  recommended  the 
study  of  illustrated  copies  to  such  of  his  monks  as  were  unable 
to  read  Greek.^     The  earliest  surviving  manuscripts  of  the  Latin 
translation  of  Dioscorides   are,   however,   of  the  ninth   century." 
Several  of  the  manuscripts  of  the  Latin  Dioscorides  contain  re- 
markable illustrations.^    The  text  has  been  printed  in  modern  times. ^ 
(ii)  The   Herbarium    bearing    falsely    the    name    of    Apuleius 

^  Cassiodorus,  Institutio  divinarum  litterarum,  c.  31  "  Si  vobis  non  fuerit 
graecarura  litterarum  nota  facundia  imprimis  habetis  herbarium  Dioscoridis  qui 
iierbas  agrorum  mirabili  proprietate  disseruit  atque  depinxit.' 

^  The  two  oldest  manuscripts  of  the  Latin  Dioscorides  are  at  the  Bibl.  Nat., 
where  they  are  numbered  9332  and  12995. 

^  Notably  the  Munich  MS.  Monac  377  of  the  tenth  century  in  the  characteristic 
Beneventan  script.  See  H.  Stadler,  Der  lateinische  Dioscorides  der  Jliinchener 
Hof-  und  Staatsbibliothek,  Janus  iv,  p.  548,  Leyden,  1899. 

^  In  Vollmoller's  Romanische  Forschungen,  i,  x,  xi,  and  xii,  Erlangen.  Cf. 
also  V.  Rose  in  Hermes,  viii,  p.  38. 


(iS         CIJKKK     KI()L()(iY    AND    ITS    liKLA'l^lOX   1X) 

IMaioiiiciis  Wits  compiled  in  Latin  pcrliaps  duriiig  tho  fifth  century. 
It  (Icscrilx's  very  briclly  llio  character  and  habitat,  and  at  jzrcater 
Icngtli  the  virtues  of  herbs,  and  it  is  possible  that  the  name  of 
ApuIeiuH  was  attached  to  it  because  he  was  the  author  of  a  Liber 
floridarutttj  which,  however,   is   of   a   totally   different    character. 
The  Hcrbarlunt  of  Apuleius  is  in  part  taken  from  tlu-  real  Dios- 
corides  and  in  part  from  the  work  known  as  the  Medlcinu  PHnii. 
At  ail  earl}^  date  the  text  became  associated  with  a  lexicon  of 
synonyms  similar  to  that  found  in  the  alf)habetical  Greek  manu- 
scripts of  Dioscorides.     Some  have  seen  in  the  character  of  these 
synonyms  evidence  of  an  African  origin  of  this  pseudo-Apuleian 
document.     The  earliest  manuscript  is  of  the  sixth  century,^  and 
already  exhibits  these  peculiar  synonyms.    There  are  a  number  of 
other  manuscripts  of  the  pseudo-Apuleius  which  contain  a  remark- 
ably   persistent    group    of    illustrations    becoming    progressively 
more    conventionalized."     The   pseudo-Apuleian    Herbarium    has 
been  printed  a  number  of  times,  usually  under  the  title  Apuleii 
Platonici  de  virtutibus  herbarum.    The  earliest  edition  was  printed  at 
Rome  before  1484  by  PhiUp  de  Lignamine.     The  printed  editions 
of  this  work,  like  the  manuscripts,,  vary  greatly  in  their  contents, 
(iii)  The  De  herbis  femininis  of  the  pseudo-Dioscorides  was  also 
written  or  rather  compiled  in  Latin.     It  is  only  about  half  the 
length  of  the  pseudo-Apuleius,  and  consists  of  a  description  of 
seventy-one  herbs  and  their  properties  without  the  synonyms. 
It  is  drawn  from  Dioscorides,  pseudo-Apuleius  and  Pliny,  relying 
perhaps  on  a  separate  Latin  version  of  the  first  of  these.     The 
earliest  manuscript  is  of  the  ninth  century,^  but  the  work  was 
probably   put   together   no    later   than   the   sixth    century,    and 
perhaps  in  Italy  during  the  domination  of  the  Goths  (493-555).* 
Manuscripts  of  this  work  in  its  pure  form  are  not  very  common.' 
It  has  also  been  printed  in  modern  times. ^ 

1  Leyden,  Voss.  lat.  Q  9. 

2  Among  the  most  ancient  of  these  are  the  Codex  Hertensis  of  the  ninth 
century,  described  by  Sudhoff  in  the  Arch,  fiir  Gesch.  der  Med.,  x,  p.  265,  Leipzig, 
1916,  and  the  Codex  Fuldensis  of  Sudhofif  of  the  tenth  century  at  Cassel,  where 
it  bears  the  pressmark  Phys.  et  hist  nat.,  fol.  10. 

3  Rome,  Barberini,  ix.  29. 

«  M.  Wellmann,  '  Krateuas  ',  in  Abh.  d.  kgl.  Gesellschaft  d.  Wissenschaften  zu 
Gottingen,  Philol.-hist.  Kla-sse,  Berlin,  1897. 

5  Ten  manuscripts  of  this  work  (one  of  which  has  been  destroyed)  are  recorded 
by  H.  Diels,  Die  Handschriften  der  antiken  Arzte,  Berlin,  1906. 

6  H.  F.  Kastner,  '  Pseudo-Dioscoridis  de  Herbis  feminis  ',  in  Hermes,  xxxi. 
p.  578,  Berlin,  1896. 


THE   RISE  OF  MODERN  BIOLOGY  69 

More  interesting  than  these  botanical  works  themselves  are 
the  paintings  of  plants  with  which  a  number  of  the*m  are  provided. 
These  were  copied  from  manuscript  to  manuscript,  century  after 
century,  without  direct  reference  to  the  objects  intended  to  be 
represented,  and  thus  arose  definite  traditions  which  can  be 
traced  in  the  representation  of  plants  from  age  to  age.  The 
traditions  of  botanical  illustration  fall  along  somewhat  different 
lines  to  those  of  the  general  history  of  manuscript  illumination, 
and  the  figures  of  j^lants  as  they  are  encountered  in  manu- 
scripts therefore  merit  a  special  study  which  has  hardly  yet  been 
accorded  them.  In  what  follows  we  shall  d,eal  mainly  with  English 
developments  which  we  have  had  most  opportunity  to  study.  There 
is  evidence  that  the  evolution  of  the  herbal  in  other  countries  took 
a  somewhat  different  course. 

Our  earliest  illuminated  Latin  herbal  is  a  sixth-century 
manuscript  (Plates  viii,  xx,  and  xxi)  probably  written  in  southern 
France.  Most  of  its  figures  are  already  stylized  and  far  removed 
from  nature  drawing.  This  model  remained  little  altered  until 
the  tenth  century,  and  herbals  of  that  period  from  the  Rhineland 
and  from  Italy  still  preserve  the  same  traditional  pictures.^  By 
then,  however,  another  treatment  of  plants  becomes  traceable  in 
northern  France.  The  figures  in  this  new  style  have  become 
symmetrical  and  heavy  and  some  of  them  approach  the  manner 
which  we  describe  below  as  Romanesque  (Plate  xxv). 

An  examination  of  a  series  of  manuscript  herbals  of  between  the 
eleventh  and  thirteenth  centuries  reveals  the  fact  that  the  figures 
fall  in  the  main  into  two  divisions,  one  of  which  we  may  call 
Naturalistic  and  the  other  Romanesque.  Both  these  divisions, 
like  other  manifestations  of  Western  culture,  were  doubtless 
derived  from  Italy,  but  it  would  appear  that  they  reached  the 
W^est  by  different  routes,  or  at  least  with  different  cultural 
waves. 

The  naturalistic  tradition  of  these  Western  herbals  of  the 
eleventh,  twelfth,  and  thirteenth  centuries  probably  took  its  rise 
in  the  south  of  Italy,  perhaps  in  that  region  where  developed  the 
])eculiar  script  to  which  the  name  of  Beneventan  has  now  become 

^  To  this  group  belong  Hertensis  192  written  in  Westphalia  (?)  in  the  ninth 
century  (cf.  Sudhofif,  Archiv  filr  Gesch.  d.  Med.  x,  p.  265,  Leipzig,  1916).  the 
Laurentian  73,  41  written  in  southern  Italy  in  the  ninth  century,  and  Cassel 
Phys.  Fol.  10  written  at  Fulda  in  tenth  century.  Munich  Lat.  337.  Italian  work 
of  the  tenth  century,  belongs  however  to  a  quite  different  tradition. 


70  GRKKK    lilOI.OCiY   AND    ITS    IlKLATTON  TO 

attached.  It  drew  on  (Jrcck  models  whieli  were  already  he^Miininj^ 
to  undergo  the  change  known  as  '  Byzantinisni  '.  In  line  with  this 
view  of  the  southern  origin  of  ceiiain  herhal  illustrations  is  the  fact 
that  a  medical  work  in  the  Anglo-Saxon  language  circulating  in 
England  in  the  twelfth  century'  was  actually  a  translation  of  a 
known  Salernitan  document,  and  English  leech-craft  of  the  eleventh 
and  twelfth  centuries  was  juofoundly  influenced  by  Salerno.'-  It 
is  of  interest  for  our  ])urpose  to  analyse  the  medical  manuscripts 
in  the  Beneventan  script  that  have  actually  survived.  Some  600 
Beneventan  manuscripts  (including  fragments)  are  known,  and 
nearly  half  of  these  are  still  lodged  at  the  Benedictine  monastery 
of  Montecassino.  The  manuscripts  vary  in  date  from  the  early 
ninth  to  the  mid-thirteenth  century  and  thus  represent  the  ]>eriod 
during  which  Salerno  was  an  important  medical  school.  Of  the 
Beneventan  MSS.,  14  (13)  or  about  2  per  cent,  are  medical.^  Of  the 
14  surviving  early  southern  medical  manuscripts  we  have  adequate 
details  of  10,  and  all  of  these  are  of  works  which  were  in  fact 
influential  in  establishing  the  main  currents  of  Dark  Age  medicine 
and  nearly  all  of  them  contain  Herbaria.  The  most  important 
perhaps  was  the  recently  destroyed  Turin  codex  of  the  eleventh 
century.  The  figures  in  this  manuscript,  a  few  of  which  have 
been  fortunately  preserved  in  photographs,  were  of  a  definitely 
Byzantine  cast  and  must  have  been  derived  from  an  earlier  Greek 
original,  and  the  influence  of  this  manuscript,  or  one  very  closely 
resembling  it,  can  be  traced  in  some  EngUsh  herbals.^    (Fig.  31.) 

The  first  herbals  brought  to  this  country  had  however  probably 
been  prepared  in  northern  France  (cf.  Betony  in  central  figure  of 
Plate  XXV  with  the  same  plant  of  Plate  xvn).  But  the  models  from 
which  the  artist  worked  must  have  betrayed  the  fullest  evidence 
of  an  origin  from  a  region  further  south,  for  traces  of  a  Mediter- 
ranean flora  may  still  be  clearly  discerned  in  the  English  copies  (cf. 
Henbane  in  Plate  xvi).  During  the  tenth,  eleventh,  and  twelfth 
centuries  there  developed  a  very  characteristic  English  school  of 
draftsmanship  and  this  new  manner  was  not  wdthout  its  influence 

^  Max  Loweneck,  '  Ilfpi  St^a^ftof,  eine  Sammlung  von  Rezepten  in  englischer 
Sprache  ',  in  the  Erlanger  Beitrdge  zur  englischen  Philologie,  ix,  Erlangen,  1896. 

2  Charles  Singer,  '  A  Review  of  the  Medical  Literature  of  the  Dark  Ages  with 
a  new  text  of  about  1110',  Proceedings  of  the  Royal  Society  of  Medicine  {section 
of  the  History  of  Medicine),  x.  102,  London,  1917. 

3  The  known  Beneventan  MSS.  are  recorded  by  E.  A.  Lowe  in  The  Beneventan 
Script,  a  study  of  the  South  Italian  minuscule,  Oxford,  1914. 

*  Especially  in  the  MS.  Harley  5294. 


o 


THE   RISE  OF  MODERN  BIOLOGY 


71 


on  the  paintings  that  adorned  the  herbals  (cf.  figures  of  Orobus 
and  Teucrium  on  Plate  v  and  of  Ivy  on  Plate  xxin). 

But  this  native  style  was,  in  turn,  largely  replaced  by  the 
Romanesque.  The  change  in  the  figures  was  accompanied  by 
a  well-marked  alteration  in  the  character  of  the  script.  These 
changes  took  place  in  England  a  generation  or  two  after  the 


Tixrin  ,  BcU^o  ^efi   Tia.yona.le  ^  G^tx  KjS.d  jh03ov 

Fig.  31.    OUTLINES   OF  THE   MANDRAKE  AND   ITS   GATHERERS 

Traced  from  a  twelfth-century  English  Herbarium  in  the  British  jNIuseum  and  a  contemporary 
Italian  Herbarium  to  illustrate  the  close  similarity. 

Conquest,  which  introduced  a  revolution  into  art  and  letters  at 
least  as  great  as  that  to  which  it  subjected  the  social  system  of  this 
country. 

On  the  Continent  the  Romanesque  method  of  plant  illustration 
had  established  itself  at  an  earlier  date.  This  style  originated  or 
at  least  emanated  from  northern  and  north-eastern  France.  Its 
ultimate  origin  appears  to  be  a  debased  style  of  Roman  art  pro- 
ceeding from  northern  Italy  and  perhaps  modified  in  Carolingian 
times  by  English  influence.  Its  characteristics,  so  far  as  plants 
are  concerned,  are  a  replacement  of  free  drawing  by  symmetrical 

F  2 


72  (JItKKK    BI()L()(;^'    AXI)    I^'S    ItKLATlOX   TO 

(it'sigM  (Plate  V,  central  figure),  vvhile  an  inereased  foriiialisin  is 
ultimately  obtained  by  the  enclosure  of  the  picture  in  a  rectilinear 
irauie  (L'hite  xxv,  lateral  figures).  As  the  style  develops,  a  back- 
ground at  first  simjile  and  afterwards  more  elaborate  is  provided. 
The  human  body  is  often  drawn  half  naked  or  even  com])letely  nude, 
and  the  dra])ery  arranged  along  characteristic  lines  (Plate  xxiv). 

Comi)aring  the  styles  we  may  characterize  the  Italian  as  more 
free  and  the  Romanesque  as  more  formal.     Both  styles  are  trace- 


gTtt^f/dictcun'imagfora.    mr 


Fig.  33.    PLANTAIN 

From  the  Herharius  latinus  printed 

at  Mainz  in  1484. 


Fig.  32.    THE    PLANTAIN 
From    a    thirteenth-century    Herbarium    in 
Romanesque     style     prepared     in     England. 
Sloane,  1975,  fo.  12  v. 

able  even  in  the  later  manuscripts  and  are  carried  over  into  the 
early  printed  herbals.  Some  manuscripts  even  contain  specimens 
of  both  styles,  and  in  all  herbals  the  centaur  holding  a  plant  is 
a  favourite  device.  It  is  noteworthy  that  in  none  of  the  English 
herbals  is  there  any  trace  of  the  influence  of  the  characteristic 
Celtic  school  of  illumination,  while  the  peculiar  and  well-known 
Anglo-Saxon  style  of  draftmanship  is  far  less  obtrusive  in  the 
books  of  plant  pictures  than  in  ecclesiastical  documents.  The 
influences  that  produced  the  herbals  were,  in  fact,  mainly  of 
a  lay  character,  but  nevertheless  a  certain  characteristic  English 
manner  of  plant  representation  can  be  detected  in  them.  This 
English  manner  had  complete^  disapj)eared  by  the  beginning  of 
the  thirteenth  century  (cf.  Sloane  1975,  Plates  xv  and  xxv). 


THE   RISE  OF  MODERN  BIOLOGY 


73 


(c)  Botany  in  the  West  from  the  twelfth  to  the  fifteenth  century 
{The  Middle  Ages) 

After  the  long  depression  of  the  Dark  Ages  the  study  of  plants 
began  to  take  an  upward  turn  at  a  much  earlier  period  than  the 
sister  study.  The  revival  begins  with  literary  rather  than  scientific 
effort,  for  neither  the  poem  called  that  of  Macer  Floridus  composed 
by  Odo  of  Meune  (died  1161),  nor  the  account  of  plants  in  the  later 


FiQ.34.    WALL-FLOWER  WITH  DODDER       Fig.  35.    YELLOW    FLAG 
Cf.  Orobus  on  Plate  v. 
From  the  German  version  of  the  Hortus  Sanitatts,  printed  at  Mainz  in  1485. 

Suhtilitatwm  diversarumque  creaturarum  liber  (early  thirteenth  cen- 
tury), wrongly  attributed  to  Hildegard  of  Bingen,  contains  evidence 
of  new  or  even  direct  observation.  More  scientific  in  spirit  is  the 
somewhat  later  work  De  vegetabilibus  of  Albertus  Magnus  (1206?- 
80).  This  is  primarily  a  compilation  based  on  the  peripatetic  work 
on  plants  by  Nicholas  of  Damascus  (first  century  B.C.),  of  which 
only  fragments  remain.  Albert's  treatise  is  essentially  a  learned 
product  and  its  author  is  hampered  by  his  desire  to  fit  the  nature 
of  plants  into  an  ill-thought-out  system,  while  his  work  is  marred 


74 


(;ki<:kk  j^ioLocn'  and  jts  jiklation  to 


by  tlic  scholastic  doctiinc  that  *"  2)hil(>s(>phi(t  is  concerned  witli 
gciicrahtics,  not  |)aiticidars  '.  It  is  a  phrase  which  itself  exj)laiiis 
the  faihire  of  scliolasticisni  to  erect  an  enduring  scientific  structure. 
But  in  spite  of  sucli  a  handicap  tlie  work  of  tliis  extraon Unary  man 
contains  esvidence  of  a  certain  amount  of  careful  first  hand  ol)serva- 
tion.  His  l)otanical  treatise  gives  a  jiot  un])leasing  ini[)ression  of 
the  common  sense  and  open-eyedness  of  the  great  mediaeval 
scholar  who  has  a  place  among  the  grandfathers,  if  not  among 
the  fathers,  of  modern  botau}'.  We  translate  one  of  his  chapters 
as  a  good  specimen  of  mediaeval  descriptive  botany. 

'  Of  the  Oak  and  its  qualities. 

'  The  oak  is  a  very  large  and  tall  tree  with  broad  branches ; 
it  has  many  roots  which  go  deep  down  and  when  old  has  a  very 
rough  bark,  but  the  young  tree  is  smooth.  It  has  great  breadth 
and  size  in  its  branches  ;  when  it  is  thriving  its  leaves  are  thickly 
set,  broad,  and  hard.  The  leaves  are  wholly  surrounded  by 
triangles,  the  bases  of  which  are  upon  the  leaf  and  the  angle  at 
the  exterior.  Many  leaves  are  attached  to  it,  but  they  fall  off. 
When  they  are  dried  up,  however,  they  still  sometimes  cling  in  large 
numbers.  Its  wood  increasing  by  straight  layers  is  compased  of 
straight  pores,  can  be  split  to  a  line  and  can  be  hewn  and  retains 
well  the  shapes  of  large  incisions,  but  in  this  box-wood  surpasses 
it.  The  outer  zone  is  of  a  pale  colour  but  towards  the  centre  it 
shades  into  a  reddish  tint.  If  it  is  put  in  water,  at  first  it  swims, 
but  at  last  sinks  owing  to  its  earthy  nature  and  then  grows  black. 
Its  fruit  is  called  acorn  {glans)  ;  it  is  not  joined  by  a  stalk  of  its 
own  to  the  branch  on  which  it  grows,  but  small  cups  spring  out 
from  the  branches  and  in  these  the  acorn  is  formed.  The  acorn 
also  has  outside  a  hard  shell  in  which  it  is  enclosed ;  this 
resembles  well-polished  wood,  shaped  like  a  column  except  that 
its  apex  is  not  a  plane  superficies  but  a  hemisphere  and  has 
a  point  in  the  middle  to  represent  the  pole.  Below  is  the  base 
of  the  acorn  through  which  it  draws  nourishment  from  the  little 
cup  ;  that  also  is  not  simply  a  plane  superficies  but  is  somewhat 
flattened  at  the  pole  ;  this  depression  is  formed  b}^  the  weight  of 
the  acorn,  for  if  it  were  an  exact  hemisphere  there  would  be  no 
place  for  the  reception  of  nourishment  except  the  point,  and 
through  that  it  could  not  receive  enough.  The  acorn  within  the 
sheath  is  surrounded  by  rind,  not  hard  but  soft,  which  is  formed 
from  the  excretion  of  the  acorn  ;  the  acorn  is  t^-isted  round  itself 
and  divided  do\\'n  the  middle  as  a  column  might  be  cut  lengthways 
by  a  plane  surface.  At  the  apex,  however,  is  the  life  germ  and 
what  is  beneath  is  of  a  floury  substance  and  is  to  be  regarded  as 
matter  and  food  for  the  germ.  The  little  cup  in  which  the  acorn 
itself  sits  is  concave  and  evenly  formed  as  if  it  were  smoothed 
on  a  lathe  inside.  The  bottom  is  somewhat  levelled  since  from 
it  the  acorn  draws  its  nourishment ;    on  the  outside  it  is  rough 


Pi.ATK  XX'Ill.     Im-oiii  llic   Pliillipps   Dioscoridcs   MS.   Xlli  c, 


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THE   RISE  OF  MODERN  BIOLOGY      / 


75 


because  of  its  own  earthy  nature  which  is  expelled  from  the 
material  of  the  acorn.  It  is  not  joined  by  any  sort  of  stem  to 
the  branch  but  sits  immediately  upon  it.  This  is  to  prevent  the 
acorn  from  being  too  far  distant  from  the  branch,  because  if  it 
had  to  draw  its  food  a  long  way,  it  would  become  hard  and  cold  and 
would  do  no  good,  especially  as  the  juice  of  this  tree  is  very  earthy. 

On  the  leaves  of  the  oak  often  grow  certain  round  ball-like 
objects  called  galls,  which  after  remaining  some  time  on  the  tree 
produce  within  themselves  a  small  worm  bred  by  the  corruption 
of  the  leaf.  If  the  worm  exactly 
reaches  the  midst  of  the  gall  apple 
weather  prophets  foretell  that  the 
coming  winter  will  be  harder :  but 
if  it  is  near  the  edge  of  the  gall 
they  foretell  that  the  winter  will 
be  mild.  .  .  .  Galls  have  a  juice 
pure  in  itself  as  long  as  the  apple 
is  green  and  moist ;  but  when  it  is 
rubbed  against  a  flat  clean  piece 
of  iron  it  immediately  is  trans- 
formed into  a  kind  of  very  black 
encaustic. 

'  The  leaves  of  the  acorn  are 
extraordinarily  astringent  but  less 
dry.  The  acorn  resembles  the 
chestnut  in  that  both  are  aster- 
sive  and  cause  flatulence  in  the 
lower  bowel ;  both  strengthen  the 
limbs  and  both  'are  good  food 
especially  for  pigs.  Galen  says 
that  the  acorn  as  well  as  the 
chestnut  is  good  for  nourishment 
and  deserves  more  praise  than  all 
the  fruits  of  growing  trees :  but  the  chestnut  is  more  nutritious 
than  the  acorn  on  account  of  its  greater  sweetness.  But  the 
food  they  afford  lacks  the  praise  of  men  because  it  is  too 
astringent,  but  if  chestnuts  are  mixed  with  sugar  they  make 
good  food ;  taken  otherwise  they  will  be  of  slow  digestion  but  the 
oak  is  even  slower.  The  astringency  in  the  inner  bark  of  the  acorn 
is  greater  than  in  the  acorn  itself.  The  leaves  of  the  oak  ground 
to  powder  and  laid  upon  wounds  make  the  flesh  unite.  The  acorn 
is  of  as  much  value  as  the  chestnut  as  a  remedy  against  poison. 

'The  juice  of  galls  darkens  the  hair:  powder  of  them  gets 
rid  of  superfluous  flesh  and  warts.  Galls  are  helpful  also  if  placed 
on  decayed  spots  of  the  teeth  and  in  many  other  medical  opera- 
tions which  must  be  determined  in  (books  on)  simple  medicines.'  ^ 
^  Translated  from  Albert's  De  vegetabilihiis ,  Lib.  VI,  Tractatus  1,  De  arboribus, 
heading  Quercus.  There  is  a  good  appreciation  of  Albert  as  a  botanist  in  E.  H.  F. 
Meyer's  Geschichte  der  Botanik,  vol.  iv,  p.  28.     Konigsbeig,  1857. 


Fig.  36.    THE    PLANTAIN 

From  Lignamine's  Apuleius.  Rome,  1483, 
printed  probably  from  metal  blocks. 


7<;  (JKKEK   BIOLOGY   AND  ITS   F.ELAT10N   TO 

III  tliis  chapter  Albert  alludes  to  the  relatioiishi])  of  galls  to 
insects.  This  was  not  mentioned  by  Aristotle  and  hardly  suspected 
by  the  ancients,  being  but  faintly  referred  to  by  Pliny.  The 
subject  had  to  await  the  microscopic  researches  of  Malpighi  to 
gain  further  elucidation.  In  the  same  passage  Albert  distinguishes 
the  two  cotyledons  of  the  acorn,  gropes  after  a  botanical  nomen- 
clature adequate  to  describe  plant  forms,  and  succeeds  in  giving 
a  description  which  would  convey  some  definite  picture  to  one 
who  had  never  seen  the  plant.  We  can  at  least  say  that  in  the 
hands  of  Albert  botany  has  begun  to  move  on  the  upward  grade 
toward  the  level  at  which  Theophrastus  left  it. 

Yet  the  scholastic  movement,  to  the  furthering  of  which 
Albert's  chief  efforts  were  directed,  was  of  its  nature  inimical  to 
the  first-hand  study  of  plants  and  animals.  The  thunders  of  the 
contest  between  Nominalism  and  Realism  might  well  drown  the 
still  small  voice  Avith  which  Nature  calls  for  direct  observation. 
The  great  scholastic  centuries  from  the  twelfth  to  the  fifteentli 
are  hardly  more  fertile  than  the  previous  period  in  botanical 
writing  exhibiting  any  first-hand  knowledge.  In  one  department 
of  intellectual  activity,  however,  there  was  some  clear  revival  of 
the  spirit  of  the  naturalist.  The  artistic  spirit  early  showed  its 
kinship  with  the  scientific  by  the  closeness  Avith  which  some 
illuminators  of  manuscripts  sought  to  imitate  nature.  The  her- 
barium itself  remained  a  fixed  text  unaltered  from  that  inherited 
from  the  preceding  age,  but  its  illustration  underwent  a  definite 
development  in  the  direction  of  increased  naturalism.  A  close 
study  of  some  of  these  beautiful  Avorks  show^s  that  the  early 
printed  herbals  had  predecessors,  and  that  already  in  the  thirteenth 
century  the  older  merely  stylistic  method  of  plants  was  giving 
place  to  a  real  attempt  to  represent  nature. 

To  explain  the  development  of  illustration  in  the  herbarium  in 
the  later  mediaeval  centuries  some  reference  must  be  made  to  the 
mode  in  which  these  volumes  were  prepared.  The  text  was  usually 
wTitten  before  the  figures  were  inserted,  and  wTiting  and  illumina- 
tion were  the  work  of  different  hands.  Thus  the  figures  are  as 
a  rule  a  little  later  and  may  occasionally  be  much  later  than  the 
text.  Sometimes  the  provenance  of  the  model  can  be  determined 
from  an  examination  of  the  figures.  Thus  in  one  of  the  figures 
from  the  Anglo-Saxon  herbarium  of  about  the  year  1000,  the  plant 
representing  the  henbane,  or  to  call  it  by  its  earHer  English  name, 
hennehelle,  is  not  our  familiar  Hyoscyamus  niger  but  Hyoscyamus 


THE   RISE  OF  MODERN  BIOLOGY  77 

reticulatus,  a  Mediterranean  form  not  found  in  this  country 
(Plate  xvi).  The  illustrator  must  have  had  an  herbarium  of  a  far 
southern  tradition  before  him  from  which  he  copied  his  figures. 
Another  proof  of  the  way  these  plant  illustrations  were  copied  has 
been  afforded  by  Fig.  31,  which  shows  the  mythical  mandrake  with 
its  roots  shaped  in  human  form.  The  form  on  the  left  is  traced 
from  a  manuscript  prepared  in  southern  Italy,  that  on  the  right 
from  a  manuscript  made  in  England  in  the  twelfth.  The  English 
figure  is  clearly  based  on  an  Italian  original. 

Now  it  must  be  remembered  that  those  who  used  these  herbaria 
had  no  idea  of  plant  distribution.  The  conception  that  flora  had 
local  peculiarities  had  been  familiar  enough  to  Aristotle  and  Theo- 
phrastus,  and  traces  of  it  can  be  found  in  Pliny  and  Dioscorides, 
but  the  idea  had  been  almost  lost  in  the  Mddle  Ages  and  remained 
obscured  until  revived  by  Euricius  Cordus.  When  the  scribe 
copied  his  text  he  was  accustomed  to  leave  a  space  of  a  particular 
size  and  shape  into  which  the  illustrator  could  then  fit  his  figure, 
and  many  herbals  have  come  down  to  us  in  which  the  illustrator 
has  either  not  completed  or  not  begun  his  work,  so  that  these 
spaces  remain  blank.  The  gaps  might  be  filled  in  later,  some- 
times centuries  later,  according  as  the  owner  of  the  book 
had  the  talent  or  the  financial  resources  at  his  disposal.  Some- 
times the  original  model  was  not  available  when  the  later 
figures  were  inserted,  so  that  these  do  not  fit  the  spaces  left 
for  them. 

Such  figures  of  plants  were  usually  copied  from  earlier  figures 
and  therefore  became  further  removed  from  nature  at  each  stage. 
But  the  degradation  of  the  copied  herbarium  had  its  limits,  and 
those  limits  were  reached  when  the  figures  had  so  utterly  deterio- 
rated that  no  semblance  to  an  indigenous  plant  could  be  discerned 
by  the  native  scribe  or  owner  of  the  book.  At  this  jDoint  it  was 
necessary  to  return  to  nature  and  to  give  some  impression  of  a  real 
and  local  plant,  though  not  necessarily  that  originally  intended 
by  the  author  of  the  text.  The  point  of  lowest  illustrational 
degradation  appears  to  have  been  generally  passed  with  the  full 
development  of  the  Romanesque  manner  at  the  end  of  the  twelfth 
or  the  beginning  of  the  thirteenth  century,  and  from  this  period 
we  can  trace  the  rise  towards  modern  botany.  But  individual 
instances  can  be  adduced  of  the  onset  of  the  change  at  an  even 
earlier  date  and  there  are  figures  of  plants  of  the  first  half  of  the 
twelfth  century  which  show  a  definite  upward  tendency  (Bodley 


78  (UIKKK    UIOJAKiV   AND   ITS   RELATION   TO 

130,  rial<s  \,  w,  and  will).  The  movement  was  continuous 
and  in  !Hanus(ii|)ts  of  the  fourtccntlj  and  tittt-cntli  centuries  we 
can  distinguish  beautiful  attemy)ts  to  imitate  nature  comparable 
in  their  degree  to  tlie  work  of  tlie  artists  wlio  (Mn|)loyed  their 
talents  on  grander  schemes  (Plate  xi,  especially  margins).  Such 
painters  of  plants  as  Leonardo  da  Vinci  and  Albrecht  Diirer  had, 
therefore,  their  humbler  craftsmen  predecessors. 

These  general  statements  require  some  modification,  for  not 
only  did  tiie  naturalistic  school  of  j)lant  illustration  ])roduce  good 
models  in  the  twelfth  century,  as  we  have  already  shown,  but 
also  in  the  thirteenth,  fourteenth,  and  fifteenth  centuries,  side  by 
side  with  real  artistic  efforts,  are  still  to  be  found  the  crudest 
and  most  wooden  imitations  of  the  outworn  models.  So  it  is  also 
with  the  earlier  printed  herbals.  Some  of  these  are  mere  repeti- 
tions of  ancient  diagrams,  some  are  real  attempts  to  represent  plant 
life  as  it  is,  some  are  a  mixture  of  the  two  types  of  illustration, 
and  some  contain  illustrations  which  are  themselves  a  mixture  of 
the  two  types.  The  early  printed  herbals  therefore  present  a  stage 
of  development  that  can  be  paralleled  in  the  manuscripts,  and  it  is 
thus  perhaps  unfortunate  that  historians  of  botany  have  usually 
elected  to  begin  their  accounts  w  ith  these  printed  w^orks.  Botany 
is  perhaps  alone  among  the  sciences  in  that  it  is  possible  to  tell 
its  history  as  an  almost  continuous  tale,  and  the  invention  of 
printing  introduces  no  specially  new  element  into  that  tale  nor 
does  it  mark  an  important  period  in  it. 

Among  the  x^urely  traditional  pictures  in  the  incunabula  we 
may  class  that  of  the  plantain  from  the  Latin  Herbarium  printed 
at  Rome  in  1484,  which  we  can  exactly  parallel  from  an  Itahan 
manuscript  of  somewhat  earher  date  (Fig.  32,  p.  72,  and  Plate  xix). 
As  a  naturalistic  representation  we  may  place  that  of  the  wall- 
flower surrounded  by  dodder  from  the  German  version  of  the 
Hortus  sanitatis  of  Mainz,  1485  (Fig.  34,  p.  73),  beside  a  figure  of 
an  Orobus  from  a  herbarium  written  and  illustrated  in  England 
early  in  the  twelfth  century  (Plate  v).  As  an  intermediate  form 
we  may  regard  the  plantain  from  the  Latin  Herbarius  latiniis  of 
Mainz  of  1484  (Fig.  33,  p.  72)  and  compare  it  with  the  Anglo- 
Saxon  effort  of  about  1000  on  the  one  hand  (Plate  xvi)  and  the 
stereotyped  thirteenth-century  forms  on  the  other  (Fig.  32,  p.  72). 
An  instructive  series  is  also  provided  by  the  plants  henbane 
(Plates  VIII,  XV,  xvi  and  xix),  Betonica  (Plates  v,  xvii,  and  xxv), 
or  Dracunculus  (Plates  xix,  xxi,  and  xxii). 


Plati:  XX.     From     Lc^'cWmi     MS.    \' o  s  s     Lat.    Q.9    A  |)  u  1  c  i  u  s    \' I  l  h    cent. 


)0€l8.g>A       y       '  ARlSToU <; »Mi<m( 


fo.  66  V    yl  r i sfoloc h  i a 


5A^ 


u^c) 


>>*W.-\,  >V,n.L. 


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hrl  10  TPoi 


).  92  V    III  lioiropia  --  Foi-i;ct-nic-not 


fo.  72  V    C  aiiuU  cii —X  yiA^KiX 


1*1. All    XXI.      I.(y<l<'ii    M.S.    X'os.s    L;ii.    (_)    (j    A  piilci  u  s    \'lili    cciu. 


X^l 


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fo.  6o  V     I)  ra  c  on  t  c  a  —  I)  r  acu  ncu  In  s    vulgaris 
A    Mediterranean    Species 


THE   RISE   OF   MODERN   BIOLOGY  79 

From  the  beginning  of  the  sixteenth  century  the  development 
of  the  Herbarium  may  be  followed  in  several  readily  accessible 
works,  and  we  need  therefore  pursue  it  no  further.^ 

VI.    The] Botanical  Results  of  Theophrastus  compared 
WITH  those  of  Early  Modern  Botanists 

{a)  Nomenclature  and  Classification  of  Plants 
We  may  now  return  to  glance  at  the  botanical  work  of  the 
Lyceum.  If  we  would  reaUze  the  course  of  ancient  botany  we 
must  mentally  sever  two  ideas  which  we  have  inherited  in  com- 
bination, viz.  the  description  of  plants  and  the  system  of  classifica- 
tion of  plants.  Unlike  investigators  of  animal  forms,  botanists  of 
the  third  and  fourth  centuries  b.  c.  had  not  developed  a  system  of 
classification.  It  is  true  that  some  would  discern  the  idea  of  plant 
families  in  the  descriptions  of  Theophrastus,  but  it  is  hardly 
l^ossible  to  draw  from  his  works  a  botanical  table  such  as  the 
zoological  table  that  we  have  extracted  from  Aristotle.  Still  less 
shall  we  find  in  Theophrastus  a  definite  technical  nomenclature. 
Even  Dioscorides  who  lived  four  hundred  years  later  and  whose 
names  for  plants  still  form  the  larger  part  of  the  popular  English 
botanical  vocabulary  is  scarcely  more  advanced  in  this  respect. 

In  the  absence  of  any  adequate  nomenclature  or  classification 
the  work  of  Theoj^hrastus  gives  at  first  a  confused  impression. 
It  is  a  descriptive  treatise  seldom  illumined  b}^  the  philosophic 
flashes  characteristic  of  the  Aristotelian  biological  writings,  and  its 
author,  unequipi^ed  with  the  exact  terms  with  which  we  can  now 
describe  plants  and  parts  of  plants,  seems  to  be  working  under 
insuperable  disadvantages.  Yet  if  we  take  trouble  to  comprehend 
his  method  we  shall  see  that  he  has  produced  a  very  scientific 
and  thorough  piece  of  investigation.  Not  only  are  the  descriptions 
almost  always  accurate  and  the  illustrations  apjiosite,  but  the 
^^Titer  is  unusually  careful  to  distinguish  his  own  observations 
from  those  which  he  has  merely  heard,  and  to  separate  hypotheses 
from  the  records  of  observations.  In  this  respect  Theophrastus 
is  unequalled  among  Greek  biologists.  But  his  work,  like  all 
Greek  biolog}^  is  marred  by  the  almost  complete  absence  of  any 
account  of  the  processes  of  investigation.    Compared  to  a  modern 

1  Agnes  Arber,  Herbals  (Cambridge.  1912),  and  J.  F.  Payne,  'The  Herbarius 
and  Hortus  Sanitatis'  {Transactions  of  the  Bibliographical  Society,  vi.  03,  London, 
1903).  A.  C.  Klebs,  '  Herbals  \  in  Papers  of  the  Bibliographical  Society  of  America, 
xi,  p.  75,  Chicago.  1917. 


80       (;kkek  J5I()ja)(;v  anj)  its  iikj.atkjn  to 

scientific  woi-k  it  is  thcicion^  l)nt  a  tVaL'incjit  coiitaininj^  tlic 
cojiclu.siojis  only. 

Wc  have  said  tliat  Tlieoi)lirastus  has  no  system  of  elassificatiou. 
It  would  ])crhaj)s  be  better  to  say  that  he  suggests  many  systems 
but  that  lie  has  discovered  no  natural  system,  and  is  fully  aware 
of  this.  He  develops,  however,  several  tentative  methods  of 
dividing  the  kinds  of  plants.  The  one  which  he  found  in  practice 
most  effective  was  a  division  into  trees,  shrubs,  under-shrubs,  and 
herbs.  Other  distinctions  are  the  common  pojnilar  divisioiis  into 
wild  and  cultivated,  flowering  and  fiowerless,  fruit-bearing  and 
fruitless,  or  again  aquatic,  terrestrial,  marsh-living,  and  marine. 
Jn  all  this  there  is  no  effective  and  permanent  scheme  of  arranging 
plant  forms,  and  this  defect  he  shares  with  all  the  older  botanical 
^vl*iters. 

Yet  the  methods  of  arranging  plants  adopted  by  Theophrastus, 
imperfect  as  they  are,  were  hardly  improved  upon  for  nearly  two 
millennia.  In  the  illustrated  manuscript  herbals  there  is  seldom 
any  grouping  of  plants  according  to  their  structure.  They  are 
usually  either  in  alphabetical  order  or  placed  according  to  their 
uses  in  healing  or  in  some  other  artificial  manner.  In  Dioscorides, 
however,  plants  are  roughly  grouped  in  some  places  according  to 
their  form,  and  occasionally  he  presents  us  with  a  series  belonging 
to  the  same  family,  e.g.  the  Compositae,  the  Lahiatae,  or  the 
Leguminosae.  The  same  tendency  is  also  encountered  in  the  fine 
Anglo-Saxon  Herbarium  of  about  a.  d.  1000  extracted  from  the 
Herbaria  of  Dioscorides  and  Apuleius.  In  this  work  there  is 
a  real  grouping  of  Umbelliferous  plants,  and  in  other  respects 
there  are  traces  of  a  rudimentary  attempt  at  a  system  of  classifica- 
tion. It  is  a  point  that  does  not  perhaps  appear  so  clearly  from 
the  printed  text  as  in  the  manuscript  itself,  but  there  is  every 
reason  to  suppose  that  such  arrangement  as  exists  cannot  be 
placed  to  the  credit  of  the  Anglo-Saxon  leech,  but  to  the  compiler 
of  the  work  from  which  he  was  translating. 

In  general  it  may  be  said  that  we  encounter  no  real  classifica- 
tion until  towards  the  end  of  the  sixteenth  century.  Among  the 
sixteenth-century  \mters  the  tendency  to  group  plants  according 
to  their  physical  characteristics  advanced  only  vrith  extreme  slow- 
ness. The  herbal  of  Brunfels  (1484-1534)  that  appeared  in  1530  ^ 
is  no  more  systematically  arranged  than  Dioscorides,  while  that  of 

^  Otto  Brunfels,  Herbarum  vivae  icones,  3  parts,  Strasburg,  1530-40 ;  also  the 
Contrajayt  Kreiiterbuch,  Strasburg,  1532 


THE  RISE  OF  MODERN  BIOLOGY  81 

Fuchs  (1501-66)  dated  1542^  is  merely  alphabetical.  Indeed  the 
rudimentary  classificatory  method  exhibited  by  Theophrastus  is 
hardly  attained  even  by  the  work  of  Bock  (  =  Tragus,  1498-1554) 
of  1546.^  The  herbal  of  Bock  is  divided  into  three  parts,  the  first 
and  second  containing  the  smaller  herbs,  the  third  the  shrubs  and 
trees.  In  Bock's  work  the  feeling  for  relationship  is  confined 
to  smaller  groups  as  with  Theophrastus,  from  whom  indeed  he 
inherits  them. 

No  satisfactory  basis  of  classification  was  in  fact  forthcoming 
until  the  appearance  of  a  description  of  a  few  plants  in  the 
Historiae  Stirpimn  by  Valerius  Cordus  (1515-44),  pubUshed  post- 
humously in  1561.-^  Cordus  was  the  first  to  suggest  the  structure 
of  the  flower  as  a  basis  of  classification,  but  his  work  was  largely 
disregarded  until  reprinted  in  the  eighteenth  century,  embedded 
in  the  botanical  \vri tings  of  Conrad  Gesner  (1516-65),''  who  had 
adopted  and  developed  the  views  of  Cordus.  As  regards  pre- 
cedence of  publication,  the  first  modern  botanist  to  attain  even 
to  the  low  classificatory  level  of  Theophrastus  was  probably 
Charles  de  I'Ecluse  (Clusius,  1526-1609),  the  books  of  whose 
Rariorum  plantarum  historia  of  1576  ^  are  divided  to  some  extent 
according  to  the  plants  of  which  they  treat,  the  first  of  trees, 
shrubs,  and  undershrubs,  the  next  of  bulbous  plants,  the  third 
of  scented  flowers,  the  fourth  of  scentless  flowers,  the  fifth  of 
poisonous,  narcotic,  and  acid  plants,  and  the  sixth  of  a  group 
containing  plants  with  milky  juice,  UmbeUiferae,  ferns,  grasses, 
Legiiminosae,  and  some  Cryptogams. 

In  de  rObel  (1538-1616)'  and  Cesalpino  (1519-1603)"  we 
encounter  at  last  two  writers  who  have  a  preponderating  interest 
in  the  arrangement  of  plants  according  to  their  natural  affinities. 
The  primary  divisions  of  de  I'Obel  are  the  traditional  ones,  trees, 
herbs,    &c.,    and    Monocotyledons    and    Dicotyledons    are    dis- 

^  Leonhard  Fuchs,  De  historia  stirpium  commentarii  insignes,  Basel,  1542. 

2  Hieronymus  Bock,  New  Kreutter  Buck,  Strasburg,  1539  ;  2nd  edition, 
\\  ith  figures,  Strasburg,  154G. 

^  Valerius  Cordus.  In  hoc  volumine  continentur  Valerii  Cordi  Annotationes  in 
Pedacii  Dioscorides  .  .  .  eiusdem  Val.  Cordi  historiae  stirpium.  .  .  .  Omnia  Conr. 
Gesneri  collecta,  Strasburg,  1561. 

*  Conrad  Gesner,  Ojjera  botanica,  1751. 

^  Charles  de  TEcIuse,  Rariorum  aliquot  stirpium  per  Hispanias  observatarum 
Historia,  Antwerp,  1576. 

^  Mathias  de  I'Obel,  Plantarum  sen  stirpium  historia,  Antwerp,  1576. 

'  Andrea  Cesalpino,  De  j^l^ntis,  Florence.  1583. 


s2       gki:i:k  riolocv  and  its  relation  to 

tiii^uislicd  ahoiit  as  clearly  as  l)y  TlK'()[)hrastiis.  His  system  of 
ciassiHcation,  like;  much  of  Thcophrastus,  is  largely  based  on 
leaf  form,  hut  he  shows  real  advance  in  the  synoptical  tables 
that  he  constructed  for  the  diagnosis  of  plant  forms.  Many  of 
these  tables  betray  a  knowledge  of  true  natural  relationships. 
(Vsalpino  brings  us  into  another  realm ;  he  pays  much  attention 
to  the  fruit,  seed,  and  flower  for  purposes  of  classification,  and 
distinguishes  clearly  tiiough  with  insufficient  em|)]iasis  between 
monocotyledons  and  dicotyledons.  He  has  at  last  passed  definitely 
beyond  Thcophrastus. 

In  the  absence  of  any  adequate  system  of  classification  almost 
all  botany  imtil  the  seventeenth  century  consisted  ])rimarily  and 
mainly  of  descriptions  of  species.  To  describe  accurately  a  leaf  or 
a  root  in  the  language  in  ordinary  use  would  often  take  pages 
and  overw^helm  the  reader  by  its  bulk.  Modern  botanists  have 
invented  an  elaborate  terminology  which,  however  hideous  to  eye 
and  ear,  has  the  crowning  merit  of  helping  to  abbreviate  scientific 
Hterature.  Botanical  writers  previous  to  the  seventeenth  century 
were  substantially  without  this  special  mode  of  expression.  It 
is  partly  to  this  lack  that  we  owe  the  persistent  attempts  through- 
out the  centuries  to  represent  plants  pictorially  in  herbals,  manu- 
script and  printed,  and  thus  the  possibility  of  an  adequate  history 
of  plant  illustration. 

Thcophrastus  seems  to  have  felt  acutely  the  need  of  botanical 
terms,  and  there  are  cases  in  which  he  seeks  to  give  a  special 
technical  meaning  to  words  in  more  or  less  current  use.  Among 
such  words  are  car^05  =  fruit,  pericarpiO)i^  seed  vessel  =  pericarp, 
and  metra,  the  word  used  by  him  for  the  central  core  of  any 
stem  whether  formed  of  wood,  pith,  or  any  other  substance. 
Thus  he  speaks  of  'the  seed  belonging  to  the  carpos  (fruit)  :  by 
carpos  is  meant  the  seeds  bound  together  with  the  pericarpion 
(seed-vessel)  '.^  It  is  from  the  usage  of  Thcophrastus  that  the 
exact  scientific  definition  of  fruit  and  pericarp  has  come  down 
to  us.-  We  may  easily  discern  also  the  purpose  for  which  he 
introduces  the  term  metra,  a  word  meaning  primarily  the  womb, 
into  botany    and   the   vacancy   in  the  Greek  language  which  it 

^  Historia  plantarum,  i.  2,  i. 

2  Though  it  is  possible  that  Theophrastus  derived  it  from  Aristotle.     Cp.  De 

Anima,  ii.    1,   412^   2.      In  the  passage   to  (f>v\Xov  -irepLKapTrCov  axeVacr/xaj  TO   Se  TTcpt- 

KapTTiov  Kapirov  in  the  De  Anima  the  word  does  not,  however,  seem  to  have  the 
full  technical  force  that  Theophrastus  gives  to  it. 


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THE   RLSE  OF  MODERN   BIOLOGY  S3 

was  made  to  fill.  '  Metra  \  he  says,  '  is  that  which  forms  the 
middle  of  the  wood,  being  third  in  order  from  the  bark  and 
corresponding  to  the  marrow  in  bones.  Some  call  this  part  the 
cardian  (heart),  others  call  it  the  enterionen  (inside),  others  again 
call  only  the  inner  part  of  the  metra  itself  the  cardian,  while 
others  distinguish  this  as  marrow.'  ^  He  is  clearly  inventing 
a  word  to  cover  all  the  different  kinds  of  core  and  importing  it 
from  another  study.  This  is  the  method  of  modern  scientific 
nomenclature  which  hardly  existed  for  the  sixteenth-century 
botanists.  The  real  foundations  of  our  modern  nomenclature 
were  laid  in  the  later  sixteenth  and  in  the  seventeenth  century 
by  Cesalpino  and  Joachim  Jung. 

(b)  Generation  arid  Development  of  Plants 

Theophrastus  understood  the  value  of  developmental  study, 
a  conception  that  he  must  have  derived  from  his  master  Aristotle. 
'  A  plant ',  he  says,  '  has  power  of  germination  in  all  its  parts  for 
it  has  life  in  all  its  parts,  wherefore  we  should  regard  them  not 
for  what  they  are  but  for  what  they  are  becoming.'  ~  The  various 
modes  of  plant  reproduction  are  correctly  distinguished  as  they 
would  be  by  any  farmer.  '  The  ways  in  which  trees  and  plants 
in  general  originate  are  these :  spontaneous  growth,  gro^^i;!!  from 
a  seed,  from  a  root,  from  a  piece  torn  off,  from  a  branch 
or  twig,  from  the  trunk  itself  ;  or  again  from  small  pieces  into 
which  the  wood  is  cut  up.'  ^  The  spontaneous  origin  of  living 
things  Avas  taken  for  granted  by  Aristotle  and  was  hardly  ques- 
tioned until  the  sixteenth  century,  Avhen,  in  a  flash  of  genius, 
Fracastor  (1478  ?-1553)  suggested  that  the  supposed  spontaneous 
generation  was  really  a  process  arising  from  undiscovered  seeds ;  * 
the  suggestion  did  not  gain  demonstration  until  the  experiments 
of  Redi  (1626-94)  in  the  seventeenth  century.^  It  is  therefore 
the  more  interesting  to  find  an  inkhng  of  this  idea  in  the  mind 
of  Theophrastus.  '  Of  these  methods ',  by  which  plants  originate, 
he  says,  '  spontaneous  growth  comes  first,  one  may  say,  but 
growth   from   seed    or   root   would   seem   most   natural ;    indeed 

^  Historia  plantarum,  i.  2,  vi. 

^  Historia  plantarum,  i.  1,  iv.  ^  Historia  plantanim,  ii.  1,  i. 

^  Girolamo  Fracastoro,  De  contagionibus  et  contagiosis  morbis,  Venice,  1546. 
See  also  Charles  and  Dorothea  Singer,  '  The  Scientific  Position  of  Girolamo 
Fracastoro,'  Annals  of  Medical  History,  i.  New  York,  1917. 

^  Francesco  Redi,  Experimenta  circa  generationem  insectorum,  Amsterdam, 
1671. 


84       grkj:k  iuolocy  and  its  relation  to 

these  inethods  too  hkii/  he  atllcd  spontaneoufi ;  wluTcforc  tliey  are 
found  v\v\\  ill  wild  kinds,  wliilo  the  rnnaining  niothods  (IojkmkI 
on  luiinan  skill  or  at  least  on  lunnan  choice,'  ' 

There  are  other  passages  in  which  Theophrastus  expnisses 
some  doubts  as  to  the  existence  of  sj)ontaneous  generation.'-  He 
quotes  the  view  of  Anaxagoras  (c.  450  B.  c.)  who  thought  that 
the  air  contained  seeds  {(TvefyfiaTa)  of  all  the  things,  plants  among 
them,  that  make  nj)  the  visible  universe,  and  contrasts  this  theory 
with  that  of  other  philosophers  who  held  that  plants  and  animals 
were  generated  de  novo  from  special  combinations  of  the  elements, 
and  then  he  observes  that  '  this  kind  of  generation  is  somehow 
beyond  the  ken  of  our  senses.  There  are  other  admitted  and 
observable  kinds,  as  \\'hen  a  river  in  flood  gets  over  its  banks  .  .  . 
and  in  so  doing  causes  a  growth  of  forest  in  that  region  that  by 
the  third  year  casts  a  thick  shade  ',  an  event  which  he  assures 
US  took  place  at  Abdera.  The  same  results  may  be  brought  about 
bj^  heavy  rains. 

*  Now,  as  the  flooding  of  a  river,  it  would  appear,  conveys 
seeds  of  fruits  of  trees  ...  so  heavy  rain  acts  in  the  same  way  ; 
for  it  brings  down  many  of  the  seeds  with  it,  and  at  the  same  time 
causes  a  sort  of  decomposition  of  the  earth  and  the  water.  In 
fact  the  mere  mixture  of  earth  with  water  in  Egypt  seems  to 
produce  a  kind  of  vegetation.  And  in  some  places,  if  the  ground 
is  mereh^  lightly  worked  and  stirred,  the  plants  native  to  the  district 
immediate^  spring  up.'  ^ 

The  process  of  germination  of  seeds  is  one  that  must  have 
awakened  admiration  from  a  very  early  date.  Even  the  Egyp- 
tians, a  people  by  no  means  observant  of  the  minute  phenomena 
of  plant  life,  were  struck  by  it,  and  in  a  bas-relief,  put  up  to 
record  one  of  the  Syrian  expeditions  of  Tethmosis  III  (about 
1500  B.C.),  we  may  discern  a  series  of  figures  illustrating  the  develop- 
ment of  seedlings  (Fig.  37).  It  is  thus  by  no  means  remarkable  that 
the  process  should  have  impressed  Theophrastus,  who  has  left  on 
record  his  views  on  the  formation  of  the  plant  from  the  seed. 

'  In  germinating  some  of  these  plants  produce  their  root  and 
their  leaves  from  the  same  point,  some  separately  from  either  end 
of  the  seed.  Wheat,  barley,  spelt,  and  in  general  all  the  cereals 
produce  them  from  either  end,  in  a  manner  corresponding  to  the 

^  Historia  plantarum,  ii.  1,  i. 

2  Theophrastus   seems,  nevertheless,  to  accept  fully  the  doctrine  of  spon- 
taneous generation  in  the  De  causis  plantarum,  i.  2. 
^  Historia  plantarum.  iii.  1,  v. 


i 


THE   RISE   OF  MODERN   BIOLOGY 


85 


YOUNG  SEEDLING 

DRACUNCULUS  BEANS 

Fig.  37.    Seedlings  from  the  '  Syrian  Garden  '  of 
Tethmosis  III  (about  1500  B.C.)  at  Kamak.^ 


position  of  the  seed  in  the  ear,  the  root  growing  from  the  stout 
lower  part,  the  shoot  from  the  upper  part ;  but  the  part  corre- 
sponding to  the  root  and  that  corresponding  to  the  stem  form 
a  single  continuous  whole.  Beans  and  other  leguminous  plants 
do  not  grow  in  the  same  manner,  but  they  produce  the  root  and 
the  stem  from  the  same  point,  namely,  the  point  at  which  the 
seed  is  attached  to  the  pod,  which,  it  is  plain,  is  a  sort  of  starting- 
point  of  fresh  growth.  In  some  cases  there  is  a  process,  as  in 
beans,  chick  peas,  and  especially  lupines,  from  which  the  root 
grows  downwards,  the  leaf  and  stem  upwards. 

'  There  are  then  these  dijfferent  ways  of  germinating  ;  but 
a  point  in  which  all  these  plants  agree  is  that  they  all  send  out 
their  roots  at  the  place  where 
the  seed  is  attached  to  the 
pod  or  ear,  whereas  the  con- 
trary is  the  case  with  the 
seeds  of  certain  trees,  as 
almond,  hazel,  acorn,  and 
the  like.  ...  In  certain  trees 
the  bud  first  begins  to  grow 
within  the  seed  itself,  and, 
as  it  increases  in  size,  the 
seeds  split — for  all  such 
seeds  are  in  a  manner  in 
two  halves  ;    and   those  of 

leguminous  plants  again  all  plainly  have  two  valves  and  are  double 
— and  then  the  root  is  immediately  thrust  out ;  but  in  cereals, 
since  the  seeds  are  in  one  piece,  this  does  not  occur  but  the  root 
grows  a  little  before  the  bud. 

'  Barley  and  wheat  come  up  with  a  single  leaf,  but  peas, 
beans,  and  chick  peas  with  several.  All  the  leguminous  plants 
have  a  single  woody  root,  and  also  slender  side  roots  springing 
from  this  .  .  .  but  wheat,  barley,  and  the  other  cereals  have 
a  number  of  fine  roots  whereof  they  are  matted  together.  .  .  . 
And  there  is  a  sort  of  contrast  between  these  two  classes  ;  the 
leguminous  plants  which  have  a  single  root,  have  many  side- 
growths  above  from  the  stem  .  .  .  while  the  cereals  which  have 
many  roots,  send  up  many  shoots,  but  these  have  no  side- 
shoots.'  " 

There  can  be  no  doubt  that  this  is  a  piece  of  first-hand  and 
minute  observation  of  the  behaviour  of  germinating  seeds.  The 
distinction  between  dicotyledons  and  monocotyledons  is  accurately 

^  These  tracings  were  made  from  photographs  kindly  taken  for  the  purpose 
by  Captain  Engelheart  of  the  Department  of  Antiquities  of  the  Egyptian  Govern- 
ment.   Cf.  also  Mariette-Bey's  Karnak,  Leipzig,  1875,  PI.  xxxi. 

^  Historia  plantarum,  viii.  1,  i. 

2391  ri 


s(;       (;im<:i:k  jiioj.cx^Y  and  jts  kej.ation  to 

set  fortli,  llion^li  the  stress  is  laid  not  so  much  on  tlic  cotvlcdoiious 
ciiaractcr  of  the  seed  as  on  tlic  relation  of  root  and  shoot.  Jn  the 
dicotyledons  the  root  and  shoot  are  represented  as  springing  from 
the  same  point  and  in  the  monocotyledons  from  opposite  poles 
in  the  seed. 

No  effective  work  was  done  oji  the  germinating  seed  until  the 
invention  of  tlic  microscope,  and  the  appearance  of  the  work  of 
Highmore  (16J.VS5)  ^  (Fig.  3H),  and  the  much  more  searching 
investigations  of  Malpighi  (1628-94)  ^  (Figs.  42  and  43)  and  Grew 
(1641-1712)  •'  after  the  middle  of  the  seventeenth  century.  The 
observations  of  Theophrastus  are,  however,  so  accurate,  so  lucid, 
and  so  complete  that  they  might  well  be  used  as  legends  for  the 
plates  of  these  writers  two  thousand  years  after  him. 

Much  has  been  written  as  to  the  knowledge  of  the  sex  of 
plants  among  the  ancients.  It  may  be  stated  that  of  the  sexual 
elements  of  the  flower  no  ancient  writer  had  any  clear  idea. 
Nevertheless,  sex  is  often  attributed  to  plants,  and  the  simile  of 
the  Loves  of  Plants  enters  into  works  of  several  of  the  poets, 
agricultural  authors,  and  writers  of  fiction.  Among  these  Achilles 
Tatius,  the  fifth-century  author  of  the  romance  The  Adventures 
of  Leucippe  and  Clitophon^  offers  a  good  example. 

'  Plants ',  we  there  read,  '  fall  in  love  with  one  another  and 
the  palm  is  particularly  susceptible.  ...  If  the  female  be  planted 
at  any  considerable  distance,  the  loving  male  begins  to  wither 
away.  The  gardener  reahzes  what  is  the  cause  of  the  tree's  grief, 
goes  to  some  slight  eminence  in  the  ground,  and  observes  in  which 
direction  it  is  drooping  (for  it  always  inclines  towards  the  object 
of  its  passion)  .  .  . '  Then  '  he  takes  a  shoot  of  the  female  palm 
and  grafts  it  into  the  very  heart  of  the  male.  This  refreshes  the 
tree's  spirit,  and  the  trunk,  which  seemed  on  the  point  of  death, 
revives  and  gains  new  vigour  in  joy  at  the  embrace  of  the  beloved  ; 
it  is  a  kind  of  vegetable  marriage.'  ^ 

Plants  are  frequently  described  as  male  and  female  in  ancient 
biological  ^Titings,  and  Pliny  goes  so  far  as  to  say  that  some 
considered  all  herbs  and  trees  were  sexual.^  Yet  when  such 
passages  can  be  tested  it  will  be  found  that  these  so-called  males 
and  females  are  usually  different  species.     In  a  few  cases  a  sterile 

1  Nathaniel  Highmore,  A  History  of  Generation,  London,  1651. 

2  Marcello  Malpighi,  Anatome  plantarum,  London,  1675. 

3  Nehemiah  Grew,  Anatomy  oj  Vegetables  begun,  London.  1672. 

*  Achilles  Tatius,  i.  17.  ^  Plinv,  Xaturalis  historia,  xiii.  4. 


THE   RISE  OF  MODERN  BIOLOGY 


87 


variety  is  described  as  the  male  and  a  fertile  as  the  female.^  In 
a  small  residuum  of  cases  dioecious  plants  are  regarded  as  male 
and  female,  but  with  no  real  comprehension  of  the  sexual  nature 
of  the  flowers.  There  remains  a  minute  group,  which  cannot  be 
extended  beyond  the  palms,  in  which  the  knowledge  of  plant  sex 
had  advanced  a  trifle  further. 


00^ 


O  C9 


Cf!,.     6"- 


(=^If-    ^■"  A 


Fig.  38.     GERMINATION    OF    SEEDS.    From  Nathaniel  Highmore's 
History  of  Generation,  London,  1651. 

■  The  tirst  figure,  of  the  first  Table,  shews  the  Kidny  Bean  opened  ;  in  which  is  a  little 
crooked  leaf  folded  up,  which  being  displayed,  shews  itself,  as  in  the  second  ;  and  when, 
being  set,  it  arises  above  ground,  it  is  such  a  Plant  as  the  third  shews,  with  the  very  same 
leaves  and  no  other. 

'  The  second  figure  shews  a  Colewort  seed  :  the  first  shews  both  leaves,  with  the  stalk 
folded  up,  as  they  lie  in  the  husk  of  the  seed  :  the  second  shews  it  come  up  out  of  the  ground. 

The  Third  Figure  hath  the  small  germen  of  an  Ash ;  lying  with  his  two  leaves  in  the 
kernel  of  an  Ash,  both  in  the  husk  inclosing  them.  The  second  shews  him  sprung  up  above  the 
Earth,  at  his  first  coming  abroad. 

'  The  fourth  delineates  fehe  young  germen  of  the  Pease  in  the  midst  of  the  grain,  and  its 
breaking  forth. 

'  The  fifth  shews  the  yoimg  Plant  in  the  midst  of  the  Bean  :  with  the  manner  of  his 
putting  forth,  with  the  same  leaves  displayed  in  the  third,  which  are  Avi'apt  up  in  the  first 
and  second. 

'  The  sixth  Figure  displayes  the  young  Maple  wrapt  up  in  his  husk ;  and  how  he  lies,  as 
in  the  first :  The  second  shews  him  a  little  unfolded,  when  it  is  taken  out  of  the  husk.  The 
third  shews  him  gotten  from  his  shell,  and  the  surface  of  the  Earth.' 

'  Common  to  all  trees  ',  Theophrastus  tells  us,  '  is  that  by 
which  men  distinguish  the  "  male  "  and  the  "  female  ",  the  latter 
being  fruit-bearing,  the  former  barren  in  some  kinds.     In  those 

^  A  good  collection  of  references  to  plant  loves  and  plant  sexes  in  classical 
A^Titings  can  be  found  in  R.  J.  Thornton's  sumptuous  New  illustrations  of  the 
sexual  of  Carolus.von  TAnnaeus,  London,  1807. 

G  2 


88 


CPvKKK    BI()L()(;V   AND    lis   KELAI'IOX   TO 


kinds  ill  wliicli  holli  foiius  arc  fniil-beariiig,  the  "female"  has 
fairer  and  more  abundant  fruit,  however,  some  call  tliese  the 
"male"  trees — for  there  are  those  who  actually  tluis  invert  the 
names.  This  difference  is  of  the  same  character  as  that  which 
distiiiiznishes  the  enltivated  from  the  wild  tree.'  '    The  description 


Figs.  39  and  40.  Supernatural  figures 
from  Nineveh  holding  male  inttoreseence  of 
date  palm  (from  Lavard). 


by  Theophrastus  of  the  fertilization  of  the  date  palm  is,  however, 
quite  clear.  '  With  dates  it  is  helpful  to  bring  the  male  to  the 
female  ;  for  it  is  the  male  which  causes  the  fruit  to  persist  and 
ripen,  and  this  process  some  call  by  analogy  (!)  the  use  of  the 
wild  fruit.  The  process  is  thus  performed  ;  when  the  male  palm 
is  in  flower  they  at  once  cut  off  the  spathe  on  which  the  flower 
is,  just  as  it  is,  and  shake  the  bloom  with  the  flower  and  the  dust 
over  the  fruit  of  the  female,  and,  if  this  is  done  to  it,  it  retains 
the  fruit  and  does  not  shed  it.'  -  The  fertilizing  character  of  the 
spathe  of  the  male  date  palm  was  familiar  in  Babylon  from 
a  ver}^  early  date,  and  is  represented  by  a  frequent  symbol  on 
the  monuments  in  which  a  divine  figure  is  represented  as  holding 

^  Historia  planfariim,  iii.  8,  i.  ^  Historia  planianan,  ii.  8,  iv. 


i 


THE   RISE  OF  MODERN  BIOLOGY 


89 


the  male  inflorescence  of  the  palm  and  fertilizing  the  female  tree 
by  shaking  it  (Figs.  39,  40,  and  41). 

The  description  of  caprification  by  Theophrastus  may  here  be 
appropriately  related.  He  tells  us  that  there  are  certain  trees, 
the  fig  among  them,  '  which  are  apt  to  shed  their  fruit  prematurely 
and  remedies  are  sought  for  this.  In  the  case  of  the  fig  the  device 
adopted   is   caprification.      Gall   insects   come   out   of    the   wild 


Fig.  41.  Assur-nasir-pal,  King  of  Assyria,  about  885-860  B.C.,  witti  winged  attendants 
holding  male '  inflorescence  of  date  palm,  performing  ceremony  of  fertilization  before  con- 
ventionalized tree.  Above  is  the  symbol  of  the  god  Assur.  From  a  bas-relief  on  the  walls  of 
the  palace  of  Assur-nasir-pal,  discovered  at  Calah  (Nimriid),  now  in  the  British  Museum. 


figs  which  are  hanging  there,  eat  the  tops  of  the  cultivated  figs, 
and  so  make  them  swell '.^  These  gall-insects  'are  engendered 
from  the  seeds.  The  proof  given  of  this  is  that,  when  they  come 
out,  there  are  no  seeds  left  in  the  fruit ;  and  most  of  them  in 
coming  out  leave  a  leg  or  wing  behind.  ...  A  fig  which  has  been 
subject  to  caprification  is  known  by  being  red  and  parti-coloured 
and  stout,  while  one  which  has  not  been  so  treated  is  pale  and 
sickly  '.^  That  Theophrastus  had  no  idea  whatever  of  the  true 
nature  of  this  caprification  he  shows  a  little  farther  on  by  observing 
that  '  in  the  case  both  of  the  fig  and  of  the  date  it  appears  that 
the  "  male  "  renders  aid  to  the  "  female  " — for  the  fruit-bearing 
tree  is  called  female — but  whilst  in  the  case  of  the  fig  there  is 
a  union  of  the  two  sexes,  in  the  case  of  the  palm  the  result  is 
brought  about  somewhat  differently  '.* 

^  Historia  plantarum,  ii.  8,  i.  ^  Historia  plantar um,  ii.  8,  ii. 

3  Historia  plantarum,  ii.  8,  iv. 


Fig.  42.      THE     GERMINATION     OF     WHEAT 
From  the  Anatome  plantarum  of  l^Ialpighi,  London,  1676. 


lA 


B 


M 


OK    THE     BEAN 


K.».43.      THE    GERMINATION     OK    TH.^^^^^^^^^^^^ 
F^„  the  4».o»e  r*"^mr.  of  MalpigH  London    18,6. 

root  nodules  may  be  seen. 


92  GHEKK    BIOLOGY   AND    ITS    RELATION   TO 

It  is  iiiicM'csiin^  to  ()l)S('rv(^  tliat  iiciodolus  (itl)()iit  .">()()  li.  c), 
(Icscribiii^  tli(^  fertilization  of  the;  date  ])alMi  in  Bal)y]on,  compares 
the  ])roce.ss  with  tliat  of  the  fig.  '  The  people  of  Ba})ylon ',  says 
Herodotus,  '  have  date-palms  growing  over  all  tlie  plain,  most  of 
them  fruit-bearing,  and  to  these  tliey  attend  in  the  same  manner 
as  to  lig-trees,  and  in  i)articular  th(iy  tak(;  the  fruit  of  those  palms 
which  the  Htillenes  call  male-palms,  and  tie  them  ii|)()n  the  date- 
bearing  ])alms,  so  that  their  gall-fly  may  enter  into  the  date  and 
ripen  it  and  tliat  the  fruit  of  the  palm  may  not  fall  off  ;  for  the 
male  palm  |)r()duees  gall-Hies  in  its  fruit  just  as  the  wild  fig  does.' ^ 

Neither  Theophrastus  nor  any  ancient  author  ever  saw  the 
flowers  of  the  fig.  These  were  first  distinguished  by  the  youthful 
botanical  genius  Valerius  Cordus  in  the  first  half  of  the  sixteenth 
century. - 

(c)  Form  and  Structure  of  Plants 

Theophrastus  was  not  successful  in  distinguishing  the  nature 
of  the  primary  elements  of  plants,  though  he  was  able  to  separate 
root,  stem,  leaf,  stipule,  and  flower  on  morphological  as  well  as 
to  a  limited  extent  on  physiological  grounds.  For  the  root  he 
adopts  the  familiar  definition,  the  only  one  possible  before  the 
rise  of  chemistry,  that  it  '  is  that  by  which  the  plant  draws  up 
nourishment  ',^  but  he  shows  by  many  examples  that  he  is  capable 
of  following  out  its  morphological  homologies.  Thus  he  knows 
that  the  ivy  regularly  puts  forth  roots  from  the  shoots  betw^een 
the  leaves,  by  means  of  which  it  gets  hold  of  trees  and  walls,* 
that  the  mistletoe  will  not  sprout  except  on  the  bark  of  Hving 
trees  into  which  it  strikes  its  roots,  and  that  the  very  pecuHar 
formation  of  the  banyan  tree  is  to  be  explained  by  the  fact  that 
'  this  plant  sends  out  roots  from  the  shoots  till  it  has  hold  on 
the  ground  and  roots  again  :  and  so  there  comes  to  be  a  continuous 
circle  of  roots  round  the  tree,  not  connected  with  the  main  stem 
but  at  a  distance  from  it  '.^  He  did  not  succeed,  however,  in 
distinguishing  the  real  nature  of  such  structures  as  bulbs,  rhizomes, 
and  tubers,  but  regards  them  all  as  roots.  Nor  was  he  more 
successful  in  his  discussion  of  the  nature  of  stems. 

1  Herodotus,  i.  493. 

2  The  passage  in  Valerius  Cordus  in  which  the  flowers  of  the  fig  are  described 
presents  certain  difficulties.  It  is  discussed  by  E.  L.  Greene,  Landmarks  oj 
Botanical  History,  Washington,  1909,  p.  292. 

3  Historia  plantarum,  i.  1,  ix.  *  Historia  plantarum,  iii.  18,  x. 
^  De  causis  plantarum,  ii.  23. 


THE   RISE  OF  MODERN  BIOLOGY  93 

As  to  leaves  he  is  more  definite  and  satisfactory  though 
wholly  in  the  dark  as  to  their  function.  In  speaking  of  them  he 
is  especially  handicapped  by  the  absence  of  a  botanical  nomen- 
clature, so  that  his  descriptions  are  seldom  more  than  comparisons 
to  well-known  objects.  '  Leaves ',  he  says,  '  differ  in  their  shape, 
some  are  round,  as  those  of  pear,  some  rather  oblong,  as  those  of 
apple  ;  some  come  to  a  sharp  point  and  have  spinous  projections 
at  the  side,  as  those  of  smilax  .  .  .  some  are  divided  and  like  a  saw, 
as  those  of  silver  fir  and  of  ferns.  To  a  certain  extent  those  of 
the  vine  are  also  divided,  while  those  of  the  fig  one  might  compare 
to  a  crow's  foot.  Some  leaves  again  have  notches,  as  those  of 
elm,  filbert,  and  oak,  others  have  spinous  projections  both  at  the 
tip  and  at  the  edges,  as  those  of  kermes-oak,  oak,  smilax,  bramble, 
Paliouros  [Christ's  thorn],  and  others.  .  .  .  Again  there  is  the  differ- 
ence that  some  leaves  have  no  leaf-stalk,  as  those  of  squill  and 
purse-tassels,  while  others  have  a  leaf -stalk.  .  .  .'  ^  He  was  well  on 
the  way,  however,  towards  arriving  at  a  correct  idea  of  the  nature 
of  certain  pinnate  leaves.  Thus  of  the  mountain  ash  he  says  that 
'  the  leaves  grow  attached  to  a  long  fibrous  stalk,  and  project  on 
each  side  in  a  row,  like  the  feathers  of  a  bird's  wing,  the  whole 
forming  a  single  leaf  but  being  divided  into  lobes  with  divisions 
which  extend  to  the  rib  ;  but  each  pair  are  some  distance  apart, 
and  when  the  leaves  fall,  these  divisions  do  not  drop  separately 
but  the  whole  wing-like  structure  drops  at  once.'  ^  Again  of  the 
elder,  '  the  leaf  is  composed  of  leaflets  growing  about  a  single 
thick  fibrous  stalk  to  which  they  are  attached  at  either  side  in 
pairs  at  each  joint ;  and  they  are  separate  from  one  another, 
while  one  is  attached  to  the  tip  of  the  stalk  ',^  and  of  the  Tere- 
binth, '  the  leaf  is  made  up  of  a  number  of  leaflets,  like  bay  leaves, 
attached  in  pairs  to  a  single  leaf-stalk.  So  far  it  resembles  the 
leaf  of  the  [mountain  ash],  there  is  also  the  extra  leaflet  at  the 
tip,  but  the  leaf  is  more  angular  than  that  of  the  [mountain  ash] 
and  the  edge  resembles  more  the  leaf  of  the  bay  '.^  These  passages 
on  the  nature  of  pinnate  leaves  are  the  more  remarkable  when 
we  recall  that  they  remained  neglected  until  similar  distinctions 
and  observations  were  published  by  Johann  Vaget  in  1678  in  his 
edition  of  the  work  of  his  master  Joachim  Jung  (1587-1657).^ 

^  Historia  plantarum,  i.  10,  v,  vi  and  vii. 

^  Historia  plantarum,  iii.  12,  vi.  ^  Historia  plantarum,  iii.  13,  v. 

^  Historia  plantarum,  iii.  15,  iii. 

^  Joachim  Jung,  Isagoge  phytoscopica,  Hamburg,  1678. 


94  CIKKKK    lil()L()(iV    AND    ITS    KKI.A'HOX    TO 

III  spite  ot  his  Ircijucnt  use  of  tlu'  terms  ^  iiiulc  and  fciiialc  ' 
as  a|»|)li('(l  to  plants,  'riicoplirastus,  as  we  have  already  said,  had 
no  correct  idea  of  the  nature  ol  sex  in  How <  is.  His  description 
ot  llowers  is  tiiiis  almost  entirely  morphological.  'Some  Howern ', 
he  says,  '  are  hair-like,  as  that  of  the  vine  .  .  .  some  are  "  leafy  " 
as  in  almond,  a|)ple,  pear,  plum.  A<4ain  some  of  these  flowers 
are  cons|)icu()Us,  while  that  of  the  olive,  though  it  is  "  leafy  ",  is 
ineoiisj)icuous  '.  The  flowers  of  annuals  are  usually,  he  says,  '  two 
coloured  aud  twofold.  1  mean  by  twofold  that  the  plant  has 
another  flower  iuside  the  Hower  in  the  middle,  as  with  rose,  lily, 
violet.  Some  flowers  again  consist  of  a  single  leaf,  [i.e.  are  gamo- 
l)etalous  or  sepalous],  having  merely  an  indication  of  more,  as 
that  of  bindweed.  For  in  the  flower  of  this  the  8ci)arate  leaves 
are  not  distinct ;  nor  is  it  so  in  the  lower  part  of  the  narcissus, 
but  there  are  angular  projections  from  the  edges.  .  .  .'  ^ 

Notwithstanding  his  lack  of  insight  as  to  the  nature  of  sex 
in  flowers,  he  attained  to  an  approximately  correct  idea  of  the 
relation  of  flower  and  fruit.  '  Some  plants ',  he  says,  '  have  the 
flower  close  above  the  fruit  as  vine  and  olive  ;  in  the  latter,  when 
the  flowers  drop  off,  they  are  seen  to  have  a  hole  through  them, 
and  this  men  take  for  a  sign  whether  the  tree  has  blossomed  well ; 
for  if  the  flower  is  burnt  up  or  sodden,  it  sheds  the  fruit  along 
with  itself,  and  so  there  is  no  hole  through  it.  The  majority  of 
flowers  have  the  fruit  case  in  the  middle  of  them,  or  it  may  be 
the  flower  is  on  the  top  of  the  fruit  case  as  in  jDomegranate,  apple, 
pear,  plum,  and  myrtle  .  .  .  for  these  have  their  seeds  below, 
beneath  the  flower,  and  this  is  most  obvious  in  the  rose  because 
of  the  size  of  the  seed  vessel.  In  some  cases  again  the  flower  is 
on  top  of  the  actual  seeds  as  in  pine,  thistle,  safflower,  and  all 
thistle-like  plants.  ...  In  some  other  plants  the  attachment  is 
peculiar  as  in  ivy  and  mulberrj',  and  in  these  the  flower  is  closely 
attached  to  the  whole  fruit-case.'  -  Thus  Theoxjhrastus,  while 
never  finally  defining  a  flower,  really  comes  gradually  to  abandon 
his  first  suggestion  that  a  flower  is  but  a  whorl  of  sx3ecially  coloured 
leaves,  and  almost  comes  to  regard  as  the  essential  floral  element 
its  relation  to  the  fruit.  He  has,  moreover,  succeeded  in  dis- 
tinguishing between  the  hypogynous,  perigjaious,  and  epigynous 
types  of  flowers. 

In  spite  of  the  discoveries  of  ^'alerius  Cordus  and  the  use  of 
flowers  for  classification  by  de  FObel  and  by  Cesalpino  in  the 

^  Historia  jilantarum.  i.  13,  ii.  ^  Historia  plantariim.  i.  13,  iii. 


J 


THE   RISE   OF   MODERN   BIOLOGY  95 

sixteenth  century,  the  sexual  character  of  flowers  remained  very 
obscure  for  a  hundred  years  after  their  time.  Grew  (1641-1712) 
in  1682  distinguished  the  stamens,  or  attire  as  he  called  them,  from 
the  outer  floral  whorls.  He  watched  the  anthers  or  semets  bursting 
and  scattering  their  pollen.  Grew  almost  ignores  the  pistil,  but 
'  in  discourse  with  our  learned  Savilian  Professor  Sir  Thomas 
Millington,  he  told  me,  he  conceived.  That  the  Attire  doth  serve, 
as  the  Male,  for  the  Generation  of  the  Seed.  I  immediately  reply'd, 
That  I  was  of  the  same  opinion  and  gave  him  some  reasons  for 
it.  .  .  .  But  withall,  in  regard  every  Plant  is  Male  and  Female, 
that  I  was  also  of  opinion.  That  it  serveth  for  the  Separation  of 
some  Parts  as  well  as  the  Affusion  of  others  '.^  Ray  (1627-1705) 
spoke  in  somewhat  similar  indefinite  terms,-  and  the  sexual 
character  of  flowers  was  onh"  cleared  up  by  the  work  of  Jacob 
Camerarius  (1665-1721)  in  the  last  decade  of  the  seventeenth 
century.^ 

(d)  Habits  and  Distribution  of  Plants 
Theophrastus  had  a  perfectly  clear  idea  of  plant  distribution 
as  dependent  on  soil  and  climate.  '  Differences  in  situation  and 
climate,  he  says,  affect  the  result.  In  some  places,  as  at  Phihppi, 
the  soil  seems  to  produce  plants  which  resemble  their  parent ;  on 
the  other  hand  a  few  kinds  in  some  few  places  seem  to  undergo 
a  change,  so  that  wild  seed  gives  a  cultivated  form,  or  a  poor 
form  one  actually  better.'  *  These  changes  he  acutely  contrasts 
to  the  metamorphoses  of  animals. 

'  In  pot-herbs ',  he  says,  '  change  is  produced  by  cultivation  ; 
for  instance,  they  say  that  if  celery  seed  is  trodden  and  rolled  in 
after  sowing,  it  comes  up  curly ;  it  also  varies  from  change  of 
soil,  like  other  things.  ...  It  would  seem  more  surprising  if  such 
changes  occurred  in  animals  naturally  and  frequently ;  some 
animals  do  indeed  seem  to  change  according  to  the  seasons,  for 
instance,  the  hawk,  the  hoopoe,  and  other  similar  birds.  .  .  .  Most 
obvious  are  certain  changes  in  regard  to  the  way  in  which  animals 
are  produced,  and  such  changes  run  through  a  series  of  creatures  ; 
thus  a  caterpillar  changes  into  a  chrysalis,  and  this  in  turn  into 
the  perfect  insect.  .  .  .  But  there  is  hardly  anything  abnormal 
in  this,  nor  is  the  change  in  plants,  which  is  the  subject  of  our 
inquiry,  analogous  to  it.    That  kind  of  change  occurs  in  trees  and 

^  Nehemiah  Grew,  The  Anatomy  of  Plants,  London,  1682,  p.  171. 

2  John  Ray,  The  Wisdom  of  God  manifested  in  the  Works  oj  the  Creation, 
London,  1691. 

^  R.  J.  Camerarius,  Ephem.  Leopold.  Carol.  Acad.,  1691,  and  De  sexu  planiarum 
epistola,  Tubingen,  1694.  *  Historia  plantarum,  ii.  2,  vii. 


96  GKKKK    HIOUKJY   AND  ITS   RELATION   TO 

ill  all  woodlaiul  plants  gciit'ially,  as  was  said  bctorc,  and  its  cilect 
is  that  Avlicii  a  chajigc  of  the  required  cliaracter  oceurs  in  the 
climatic  conditiojis,  a  Kj)ontaneous  change  in  the  way  of  growth 
ensues.'  * 

He  is  very  clear  as  to  the  difference  })et\veen  the  vegetation 
of  mountain  and  jilain,  and  gives  formal  hsts  to  illustrate  it." 

'  Again  the  character  of  the  position  makes  a  great  difference 
as  to  fruit-bearing.  The  persea  of  Egypt  bears  fruit  .  .  .  Vjut  in 
Rhodes  it  only  gets  as  far  as  flowering.  The  date-palm  in  the 
neighbourhood  of  Babylon  is  marvellously  fruitful  ;  in  Hellas  it 
does  not  even  ripen  its  fruit,  and  in  some  places  it  does  not  even 
produce  any.'  '  That  each  tree  seeks  an  apy^ropriate  position 
and  climate  is  plain  from  the  fact  that  some  districts  bear  some 
trees  but  not  others  ;  the  latter  do  not  grow  there  of  their  own 
accord,  nor  can  they  easily  be  made  to  grow,  and  that  even  if 
they  obtain  a  hold,  they  do  not  bear  fruit.  .  .  .  Thus  in  Egyjjt 
there  are  a  number  of  trees  which  are  pecuHar  to  that  country, 
the  sycamore,  the  tree  called  persea  .  .  .  and  some  others.  Now 
the  sycamore  to  a  certain  extent  resembles  the  tree  which  bears 
that  name  in  our  country.  Its  leaf  is  similar,  its  size,  and  its 
general  appearance  ;  *but  it  bears  its  fruit  in  a  quite  pecuUar 
manner  .  .  .  not  on  the  shoots  or  branches,  but  on  the  stem ;  in 
size  it  is  as  large  as  a  fig.'  ^ 

At  times  Theophrastus  seems  to  be  on  the  point  of  passing 
from  a  statement  of  climatic  distribution  into  one  of  real  geo- 
graphical regions.     Thus : 

*  Among  the  plants  that  grow  in  Arabia,  Syria,  and  India  the 
aromatic  plants  are  somewhat  exceptional  and  distinct  from  the 
plants  of  other  lands  ;  for  instance,  frankincense,  m5rrrh,  cassia, 
balsam  of  Mecca,  cinnamon,  and  all  other  such  plants.  ...  So  in 
the  parts  towards  the  East  and  South  there  are  these  special 
plants  and  many  others  besides. 

'  In  the  northern  regions  it  is  not  so,  for  nothing  worthy  of 
record  is  mentioned  except  the  ordinary  trees  which  love  the  cold 
and  are  found  in  our  country.'  ^ 

The  general  question  of  plant  distribution  long  remained  at, 
if  it  did  not  recede  from,  the  position  where  Theophrastus  left  it. 
The  usefulness  of  the  manuscript  and  early  printed  herbals  was 
marred  by  the  retention  of  plant  descriptions  prepared  for  the 
Greek  East  or  Latin  South,  and  these  works  were  saved  from 
complete  ineffectiveness  only  by  an  occasional  appeal  to  nature. 

^  Historia  plantarum,  ii.  4,  vi.  and  vii.  ^  Historia  plantarum,  iii.  1,  1. 

^  Historia  plantarum,  iii.  3,  v.  ^  Historia  plantarum,  iv.  1,  v. 


Ji 


I 


THE   RISE  OF  MODERN  BIOLOGY  97 

Euricus  Cordus  (1486-1535)  was  perhaps  the  first  to  reahze  that 
there  was  only  a  general  and  not  a  specific  correspondence  between 
the  plants  of  middle  Europe  and  those  of  the  Mediterranean  region 
known  to  Dioscorides.  With  the  extension  of  travel  in  the  prepara- 
tion of  works  on  exotic  botany  such  as  those  of  Oviedo,  Clusius 
ajid  Acosta,  this  point  gradually  came  into  clearer  view,  but  the 
conception  of  botanical  regions  was  a  very  slow  growth. 

Theophrastus  does  not  abandon  the  doctrine  of  plant  meta- 
morphosis and  he  applies  this  view  especially  to  the  transformation 
of  corn  into  tares.  '  They  say ',  he  says,  '  that  wheat  and  barley 
change  into  darnel,  and  especially  wheat ;  and  that  this  occurs 
with  heavy  rains  and  especially  in  well  watered  and  rainy  districts.' 
It  is  a  fact  that  in  damp  fields  the  Lolium  is  hable  to  spring  up, 
and  this  event,  it  is  said,  is  still  held  by  farmers  to  be  of  the 
nature  of  a  metamorphosis.  Theophrastus,  though  he  does  not 
deny  that  this  is  a  metamorphic  process,  expresses  his  doubts. 
'  That  darnel ',  he  says,  '  is  not  a  plant  of  the  spring  hke  others 
(for  some  endeavour  to  make  this  out)  is  clear  from  the  following 
consideration :  it  springs  up  and  becomes  noticeable  directly  winter 
comes ;  and  it  is  distinguished  in  many  ways;  the  foUage  is  narrow, 
abundant,  and  glossy.'  ^ 

In  the  case  of  the  Lolium  Theophrastus  rightly  expresses  his 
disbelief  in  a  dimorphism  or  transformation  that  we  now  know 
does  not  exist.  There  is  another  case  in  which  a  plant  exhibits  two 
stages  of  development  that  were  almost  invariably  regarded  by  the 
ancients  as  separate  species.  The  habit  of  the  ivy  is  to  develop 
a  cHmbing  shoot  well  provided  with  rootlets  which  hold  it  to  its 
support.  The  climbing  shoot  is  beset  with  dark  angular  foliage. 
After  reaching  the  top  of  the  object  on  which  it  is  climbing  there  sets 
in  an  extensive  production  of  free  terminal  branches  bearing  some- 
what paler  and  larger  ovate  leaves.  On  these  terminal  twigs  the 
fiowers  are  born,  and  often  the  production  of  the  terminal  growth 
becomes  so  extensive  as  to  conceal  the  climbing  portion.  In  ancient 
times,  as  in  the  Middle  Ages  and  indeed  into  quite  modern  times, 
these  two  stages  in  the  development  of  the  ivy  were  regarded 
as  two  species  (Plate  xxiii).  The  climbing  plant  was  named  by 
the  Greek  helix  and  the  bushy  terminal  growth  cittus  or  chrysa- 
canthus.     Theophrastus,  however,  ventures  to  traverse  this  view. 

'The  helix\  he  says,  'presents  .  .  .  differences  in  the  leaves, 
which  are  small,  angular,  and  of  more  graceful  proportions,  while 

^  Hisforia  jtJantaruyn,  viii.  7,  i. 


98  (JI^KKK    RI()I.()(;V    AND    ITS    IIKLA'IMON     I^O 

lliost'  oi  tlic  cillKs  arc  rounder  and  simple;  llicic  is  also  dili'cr- 
ence  in  the  length  of  the  twigs,  and  iiirlhcr  in  th(;  fact  that 
this  tree  is  haricn.  iM)r  as  to  the  view  that  the  liclix  hy  natural 
development  turns  into  the  clllu.s  somi;  assert  that,  tliis  is  not  ho, 
the  only  true  ivy  aeeoiding  to  these  being  that  which  was  ivy 
from  tlie  first  ;  wlieicas  if,  as  some  say,  the  h(;lix  invariably  turns 
into  [cittus],  the  difference  would  be  merely  ojk;  of  age  and  con- 
dition and  not  of  kind.'  ^ 

We  may  terminate  our  discussion  with  a  summary  of  tlic 
botanical  position  of  Thcophrastus  : 

1.  He  distinguished  the  external  organs  of  ])lants,  naming 
them  in  regular  sequence  from  root  to  fruit,  and  attained  in  many 
cases  to  a  really  philosophical  distinction. 

2.  He  definitely  set  forth  the  leaf  homology  of  the  perianth 
members  of  flowers  but  attained  to  no  real  knowledge  of  their 
sexual  nature. 

3.  He  established  the  first  rudiments  of  a  botanical  nomen- 
clature. 

4.  He  watched  the  development  of  seeds  and  was  able  to  some 
extent  to  distinguish  between  dicotyledons  and  monocotyledons. 

5.  He  established  a  relationship  between  structure  and  habits 
and  approaches  the  conception  of  geographical  distribution. 

6.  He  saw  the  need  for  a  general  classification  of  plants  and 
made  some  attempt  at  a  system  though  he  failed  to  produce  one 
which  was  in  fact  Avorkable. 

7.  He  perceived  a  general  relation  between  structure  and 
function  in  plants,  and  thus  laid  the  basis  of  scientific  botan}^ 

Note. — I  have  to  thank  many  friends  for  much  kind  help 
during  the  preparation  of  this  essay. 

Mrs.  Agnes,  Arber  and  Professor  D'Arcy  Thompson  read  the 
M'ork  in  manuscript  and  made  a  number  of  corrections  and 
emendations. 

Professor  Sudhoff  has  most  generously  handed  over  to  me 
a  large  collection  of  photographs  of  early  herbals  which  must 
have  taken  years  to  put  together.  It  is  a  source  of  great  regret 
to  me  that  these  photographs  reached  me  too  late  for  full  use  in 
illustration  of  my  text.  I  have,  however,  been  able  to  include 
figures  of  the  Leyden  Apuleius  and  it  is  a  pleasure  to  me  to 

^  H istoria  plantarum ,  iii.  18,  vii. 


THE   RLSE   OF  MODERN   BIOLOGY  99 

acknowledge  that  I  owe  my  acquaintance  with  tliat  important 
document  and  many  others,  including  the  frontispiece  of  this 
book,  entirely  to  his  good  offices.  In  a  later  publication  I  hope 
to  display  more  fully  the  rich  vein  of  treasure  which  the  generosity 
of  this  eminent  scholar  has  placed  at  my  disposal. 

I  am  grateful  to  Mr.  Henry  Balfour,  Dr.  A.  H.  (Jhurch,  Pro- 
fessor F.  J.  C'ole,  Professor  Clifford  Dobell,  Dr.  Claridge  Druce, 
Professors  Ernest  and  Percy  Gardner,  Mr.  E.  A.  Lowe,  Mr.  Eric 
Maclagan,  Mr.  F.  S.  Marvin,  Professor  F.  W.  Oliver,  Mr.  C.  Tate 
Regan,  Mr.  R.  R.  Steele,  and  Dr.  W.  J.  Turrell  for  a  number  of 
suggestions  that  they  have  made. 

For  the  loan  of  the  blocks  of  Plates  vi  and  vii  illustrating  the 
Julia  Anicia  MS.  I  have  to  thank  Mrs.  Arber  and  the  (*ambridge 
University  Press.  Plate  xviii  of  the  Phillipps  Dioscorides  is  from 
photographs  taken  for  me  by  Mr.  E.  A.  Lowe  by  kind  permission 
of  the  then  owner,  Mr.  Fitzroy  Fenwick.  The  Paris  Bibliotheque 
nationale  MSS.  lat.  6862  and  gr.  2179  were  examined  for  me  by 
Miss  A.  Anderson  who  has  helped  me  also  with  many  details 
of  the  work.  Miss  C.  Hugon  has  redrawn  many  of  the  text 
figures  and  has  been  of  great  assistance  in  the  preparation  of 
the  plates. 

In  quoting  passages  from  the  works  of  Aristotle  I  have  used 
the  translations  of  Professor  D'Arcy  Thompson,  Professor  A.  Piatt, 
and  the  late  Dr.  Ogle  in  the  Oxford  Aristotle.  The  only  deviation 
I  have  made  has  been  the  restoration,  in  a  few  cases,  of  the  Greek 
term  for  that  used  by  the  translator.  In  every  case  I  have  given 
the  reference  by  page  and  line  to  Bekker's  Greek  text.  For  the 
History  of  Plants  of  Theophrastus,  the  translation  by  Sir  Arthur 
Hort  has  been  followed.  In  one  instance,  however  {Historia 
plantarum,  i.  1,  iv,  p.  83  of  my  essay)  I  have  ventured  to  diverge 
from  it.  To  all  these  writers  and  to  their  publishers,  the  Clarendon 
Press,  and  the  Loeb  Classical  Library,  my  thanks  are  due  for 
permission  to  avail  myself  of  these  translations.  There  is  no 
English  version  of  the  De  causis  plantarum  and  for  that  I  have 
used  Wimmer's  text. 

The  Appendix  contains  a  list  of  Aristotelian^MSS.  abstracted 
from  the  Catalogue  of  Scientific  and  Medical  MSS.  in  the  British 
Isles  that  is  being  prepared  by  my  wife.  She  has  helped  me  in 
innumerable  Avays  and  the  revision  of  the  proofs  has  been  her 
work. 


100 


(;iiKr:K  biology  and  its  hklation  to 


APPENDIX 

MSS.    IX    KX(;LISH   LIBRARLES   of   ARISTOTELIAN 
P.TO LOGICAL   WORKS 

A  list  of  the  MSS.  as  they  exist  in  ilic  |)ul)li<;  libraries  of  this  country  is 
here  given.  Eoi-  convenience  of  reference  the  (Jreek  MSS.  have  been  included 
in  the  list  l)ut  not  in  the  suinnuiry  at  the  end.  AH  MSS.  are  Latin  unless 
otherwise  described.     Many  give  abridged  versions  of  the  works. 

The  time  distribution  of  the  MSS.  is  significant.  It  does  not  suggest  any 
revived  interest  in  Ari.stotelian  biology  with  the  revival  of  Greek  learning 
in  the  fifteenth  century.  On  the  contrary,  the  number  of  Aristotelian 
biological  MSS.  of  the  fifteenth  century  is  but  a  third  of  that  of  the  fourteenth. 
Tiie  fall  in  numbers  in  the  fifteenth  century  cannot  be  explained  by  the 
advent  of  printing,  since  the  number  of  medical  and  scientific  MSS.  of  almost 
every  class  of  the  fifteenth  century  is,  in  fact,  greater  than  of  the  fourteenth 
century. 


Historia  animalium 


1. 

2. 

3. 

4. 

5. 

6. 

7. 

8. 

9. 
10. 
11. 
12. 
13. 
14. 
15. 
16. 
17. 


1. 

2. 
3. 
4. 
5. 
6. 

s! 

9. 
10. 


Imperfect    .  .  .  . 

Translation  by  Michael  Scot  . 
Translation  bv  Michael  Scot. 


British  Museum  :  Royal  9  A  XIV. 
British  Museum  :  Royal  12  C  XV. 
British  Museum  :    Roval  12  F  XV. 

Oxford  :    Balliol  250  ' 

Oxford:    Balliol  252 

Cambridge  :   Gon.  &  Caius  109.     Translation  by  IMichael  Scot 
Cambridge  :   Peterhouse  121      . 

Cambridge  Univ.  Lib.  li.  III.  16.     Translation  by  Michael  Scot     . 
Salisbury  Cathedral  111.  .  .  .  .  ... 

British  Museum  :    Harley  4970  ........ 

British  Museum  :    Royal  7.  C.  I.     Translation  by  Michael  Scot 

Oxford  :   All  Souls  72.     Avicenna's  paraphrase    ..... 

Oxford  :   Merton  27S.     Translation  by  ]\Iichael  Scot     .... 

Cambridge  Univ.  Lib.  Dd.  IV.  30.     Translation  by  Michael  Scot  . 
Oxford  :   Bod.  Can.  misc.  418    .  .  .  .  .         .  ?  early  15th, 

Oxford  :   Bod.  Barocci  95.     Excerpts.     Greek  ..... 

Lincoln  Cathedral  B.  6.  4.     Begins  imperfectly    ..... 


13th  century. 

13th 

13th 

13th 

13th 

13th 

13th 

13th 

13th 

14th 

14th 

14th 

14th 

14th 

14th 

15th 

15th 


8. 

9. 

10. 


De  partibus  animalium 

Oxford  :  C.C.C.  108.     Greek.     Ends  imperfectly 

British  Museum  :   Royal  9  A  XIV.     ..... 

British  Museum  :   Royal  12.  F.  XV.     Ends  Imperfectly 

Cambridge  :   Peterhouse  121      . 

Cambridge  Univ.  Lib.  li.  III.  16 

British  Museum  :   Harley  4970 ...... 

British  Museum  :   Royal  7.  C.  1.     Translation  bv  Michael  Scot 
Oxford:   Merton  270"^       ....'... 

Oxford  :   Merton  271 

Oxford  :   Bod.  Can.  misc.  412    . 

De  generatione  animalium 

Oxford  :  C.C.C.  108.     Greek 

British  Museum  :   Royal  9.  A.  XIV    .... 

Cambridge  :    Peterhouse  121       . 

Cambridge  Univ.  Lib.  li.  III.  16         .  .  .  . 

British  Museum  :   Harley  4970  .  .  .  . 

British  Museum  :   Roval  7.  C.  I.     Translation  by  Michael  Scot 

Oxford:   Merton  270 '        .  .  .  .         ". 

Oxford  :   Merton  271 

Oxford  :    Bod.  Can.  misc.  412    ..... 
Oxford  :   New  Coll.  226 


late  12th  century. 
13th 
13th 
13th 
13th 
14th 
14th 
14th 
14th 
early  15th         ,, 


late  12th  centurv. 
13th 
13th 
13th 
14th 
14th 
14th 
14th 
earlv  15th 
/   15th 


i 


THE   RISE  OF  MODERN  BIOLOGY 


101 


De  incessu  animalium 


1. 

2. 

3. 

4. 

5. 

6. 

7. 

8. 

9. 
10. 
11. 
12. 


1. 
2. 

3. 

4. 

5. 

6. 

7. 

8. 

9. 
10. 
11. 
12. 
13. 
14. 
15. 


1. 

2. 

3. 

4. 

5. 

6. 

7. 

8. 

9. 
10. 
11. 
12. 
13. 
14. 
15. 
16. 
17. 
18. 


Oxford  :   C.C.C.  108.     Greek 
Oxford:   Balliol250 
Cambridge  :   Peterhouse  121 
Cambridge  :    Peterhouse  190 
Cambridge  :   Fitzwilliam.  155 
Oxford  :   Balliol  232  A      . 
Oxford  :  Trinity  67 . 
Oxford:   Merton  271 
Cambridge  Univ.  Lib.  li.  II.  10. 
Oxford  :   Bod.  Can.  misc.  418 
Oxford  :   New  Coll.  226.     Greek 
Cambridge  Univ.  Lib.  Mm.  III.  11. 


Extracts 


De  motu  animalium 

Oxford:   Balliol  250 

Oxford:   Balliol  250.     Fragment 

Cambridge  :   Peterhouse  12 

Cambridge  :   Fitzwilliam  154 

Cambridge  :   Fitzwilliam  155 

British  Museum  Add.  19582 

Oxford  :    Bod.  Can.  Lat.  auct.  290 

Oxford  :   Merton  270 

Oxford  :   Balliol  232  A      . 

Oxford:   Trinity  67. 

Cambridge  Univ.  Lib.  li.  II.  10 

Oxford  :   Bod.  Can.  misc.  412 

Oxford  :   Bod.  Digby  44.     Extracts 

Oxford:  Xew  Coll.  226.     Greek 

Cambridge  Univ.  Lib.  Mm.  III.  11.     Extracts 


Oxford  :   Bod.  Auct.  F.  5.  31 
Oxford:   C.C.C.  114. 
Cambridge  :   Gon.  &  Caius  409. 
Cambridge  :   Gon.  &  Caius  452 
Cambridge  :   Gon.  &  Caius  506 
Cambridge :   Fitzwilliam  154 
British  Museum  :   Harley  3487 
British  Museum  :   Add.  19582 
Oxford  :    Bod.  Can.  Lat.  auct.  291 
Oxford  :   Balliol  232  A      . 
Oxford:  C.C.C.  111. 
Cambridge  Univ.  Lib.  li.  II.  10 
Durham  Cathedral  C.  III.  17 
Durham  Cathedral  C.  IV.  18 
British  Museum  :   Sloane  2459 
Oxford  :   Bod.  Bodley  675 
Oxford:  C.C.C.  113.     Greek 
Cambridge :   Peterhouse  184 


De  plantis 


Fragment 


Summary  of  Latin  Textb 


12th  centurv 
13th 
14th 
15th 


No. 


late  12th  century. 
.  13th 

.  13th 

.  13th 

.  13th 

.  14th 

.  14th 

.  14th 

.  14tb 

early  15th 
.  15th 

.  15th 

13th  century 
13th 

13th 

13th 

13th 

14th 

14th 

14th 

14th 

14th 

14th 

15th 

15th 

15th 

15th 

12th  century 
.  13th 

.  13th 

.  13th 

13th 

.  13th 

14th 

14th 

14th 

14th 

14th 

14th 

14th 

14th 

15th 

15th 

.  15tb 

.  15th 

of  MSS. 

1 

30 

32 

12 

2391 


MEDTAKVAL   ASTRONOMY 

I^V    .1.     L.     K.     DllHVKR 

The  study  of  Mediaeval  ('Osmology  and  Astronomy  has 
hitherto  not  attracted  many  students.  This  is  perliaps  partly 
due  to  the  fact  that  the  jieriod  in  question  is  one  of  stagnation, 
during  which  astronomy  made  absolutely  no  progress  in  Christian 
countries,  while  the  high  state  reached  by  science  at  Alexandria 
had  gradually  to  be  won  back.  But  the  chief  reason  of  the 
neglect  is  that  many  interesting  writings  from  the  Middle  Ages 
have  never  been  printed  and  have  therefore  to  be  looked  for 
among  the  manuscript  treasures  in  great  libraries,  particularly 
in  the  Bibliotheque  Nationale  at  Paris.  The  great  work  of 
M.  Pierre  Duliem,  Le  Systeme  du  Monde,  Histoire  des  Doctrines 
cosmologiques  de  Platon  a  Copernic,^  is  therefore  particularly 
welcome,  and  it  is  quite  up  to  the  high  standard  of  excellence  of 
his  previously  published  historical  works,  fJtudes  sur  Leonard  de 
Vinci  and  Les  Origines  de  la  Statique.  80  far,  five  volumes  of 
more  than  five  hundred  pages  each  have  been  published,  and  it 
is  remarkable  that  so  great  a  work  should  have  appeared  in  France 
during  the  terrible  struggle  in  which  that  country  was  then  in- 
volved. The  five  volumes  reach  to  the  beginning  of  the  fifteenth 
century  ;  and  how  far  the  work  will  be  continued  may  be  doubtful, 
as  the  death  of  the  author  was  announced  in  1916.  It  was  stated 
in  the  Paris  Academy  in  December  1916  -  that  the  work  Avas  to 
have  been  completed  in  ten  volumes,  and  that  the  fifth  and  sixth 
had  been  entrusted  by  M.  Duhem's  daughter  to  the  Academy. 
The  fifth  volume  appeared  in  1917.  But  even  if  not  completed 
according  to  the  original  plan,  the  work  will  be  of  exceptional 
interest  on  account  of  the  great  number  of  manuscripts  which 
M.  Duhem  has  examined,  and  from  which  he  has  given  lengthy 
extracts. 

The  work  is  (so  far)  divided  into  three  parts.  '  Greek  Cos- 
mology '  occupies  the  first  volume  and  four-fifths  of  the  second 

1  Paris,  A.  Hermann  et  Fils,  5  vols.,  1913-17. 
-  Comptes  rendus,  December  18,  1916. 


MEDIAEVAL  ASTRONOMY  103 

one.  '  Latin  Astronomy  in  the  Middle  Ages '  reaches  to  tlie 
middle  of  the  fourth  volume,  and  is  followed  by  '  The  rise  of 
Aristotelism  ',  which  at  the  end  of  the  fifth  volume  is  carried  as 
far  as  Thomas  Aquinas.  As  Greek  Cosmology  has  been  dealt 
with  in  two  works  published  in  England  during  the  last  fifteen 
years,  that  part  of  M.  Duhem's  work  does  not  call  for  special 
notice  in  this  place.  Neither  do  the  chapters  of  Part  T  dealing 
with  Arabian  astronomy  (which  the  author  considers  as  a  mere 
continuation  of  Greek  science)  contain  anything  new.  As  a  rule, 
the  author  shows  a  thorough  acquaintance  with  the  literature  of 
his  subject,  though  we  have  in  a  few  cases  failed  to  find  references 
to  important  works,  such  as  the  Liber  Jesod  Olam  of  Isaac  Israeli 
or  Le  livre  de  F Ascension  de  V esprit  of  Abu'l  FaraJ.  It  is  par- 
ticularly the  chapters  dealing  with  Latin  Astronomy  in  the  Middle 
Ages  w^hich  will  be  of  permanent  value,  as  they  give  accounts  of 
many  manuscript  treatises  never  before  described. 

The  last  great  astronomer  of  the  Alexandrian  school,  Claudius 
Ptolemy  (about  a.  d.  140),  wrote  a  complete  compendium  of 
ancient  astronomy  as  finally  developed  by  Hipparchus  and 
himself.  During  the  270  years  which  had  elapsed  since  the  days 
of  Hipparchus  astronomy  had  certainly  not  stood  still,  but  we 
know  next  to  nothing  about  the  progress  made,  as  Ptolemy  gives 
very  little  historical  information.  The  details  given  by  Pliny 
about  the  situations  of  the  apsides  of  the  excentric  orbits  of  the 
planets  show,  however,  that  Ptolemy  had  more  than  the  work  of 
Hipparchus  to  build  on.  Pliny's  source  was  no  doubt  the  book 
De  novem  disciplinis  by  M.  Terentius  Varro,  which  is  unfortunately 
lost.  It  seems  to  have  been  a  sort  of  condensed  encyclopaedia, 
and  was  superseded  by  writings  of  a  similar  kind  from  the  fourth 
and  fifth  centuries  which  have  come  down  to  us.  These  are, 
the  commentary  to  Plato's  Timaeus  by  Chalcidius,  the  commentary 
to  Cicero's  Somnium  Scipionis  by  Macrobius,  and  the  encyclo- 
paedic book  De  nuptiis  Philologiae  et  Mercurii  by  Martianus 
Capella.  Being  written  in  Latin  they  were  more  readily  accessible 
to  Western  readers  than  the  lengthy  Greek  works  of  Proklus  and 
Simplicius  ;  and  during  the  first  half  of  the  Middle  Ages  they  were, 
together  with  Pliny's  Natural  History,  the  only  books  from  which 
some  knowledge  of  Greek  science  might  be  derived  by  students 
in  the  West. 

The   first  feeble  light   after  the  dark  night   of  the  patristic 

H  2 


104  MKI)IAI':\A1.   A.STUO.NOMV 

writcr.s  caiuc  Irom  Isidore,  liislioj)  of  Seville,  wlio  died  iji  (i.'jO, 
When  dealiii*;  with  daii^eroii.s  toj)ic.s  sucli  as  tli(^  figure  of  the 
world  and  the  eartli  he  does  not  lay  down  tiie  law  hiniself,  but 
quotes  '  I  lie  pliilosophers  '  as  teaching  this  or  that,  though  witliout 
finding  faidt  with  them.  In  this  manner  he  repeatedly  mentions 
that  heaven  is  a  sphere  rotating  round  an  axis  and  havijig  the 
spherical  earth  in  its  centre.  The  water  above  the  firmament 
mentioned  in  the  first  chapter  of  Genesis  had  of  course  to  be 
brought  in,  and  Isidore  states  that  the  Creator  tempered  the 
nature  of  heaven  with  water,  lest  the  conflagration  of  the  upi)er 
fire  should  kindle  the  lower  elements.  Isidore  gives  as  his  authori- 
ties Hyginus  (author  of  a  versified  description  of  the  constella- 
tions), Clement  of  Alexandria,  and  the  patristic  writers,  but  does 
not  mention  Phny,  so  that  it  is  no  wonder  that  his  knowledge  is 
very  fragmentary. 

The  Venerable  Bede,  who  Uved  a  century  later  (he  died  about 
735),  w^as  better  informed.  The  contents  of  his  treatise  De 
Nat  lira  Rerum  are  taken  from  Pliny,  often  almost  verbatim  ;  and 
the  spherical  form  of  the  earth,  the  order  of  the  seven  planets 
circling  round  it,  the  sun  being  much  larger  than  the  earth,  and 
similar  facts  are  plainly  stated.  But  the  water  around  the  heaven 
and  the  usual  explanation  of  its  existence  could  not  be  kept  out 
of  the  book,  even  though  Pliny  did  not  mention  it  and  though 
Bede  had  stated  that  the  earth  was  a  sphere.  Another  and  much 
larger  book  on  chronology  {De  Temporum  Ratione)  shows  a  fair 
knowledge  of  the  annual  motion  of  the  sun  and  the  other  principal 
celestial  phenomena.  It  is  deserving  of  notice  that  Bede  from  his 
study  of  Pliny  and  from  personal  observation  knew  a  good  deal 
about  the  tides,  and  was  the  first  to  show  that  the  '  establish- 
ment '  of  a  port  (or  the  mean  interval  between  the  time  of  high 
water  and  the  time  of  the  moon's  previous  meridian  passage)  is 
different  for  different  ports.  But  the  sphericity  of  the  earth  was 
still  rather  unpopular  among  ecclesiastics,  and  even  in  the  first  half 
of  the  ninth  century  Hrabanus  Maurus,  Archbishop  of  Mainz, 
thought  it  best  to  say  nothing  about  it.  He  merely  says  that  the 
earth  is  in  the  middle  of  the  world,  and  tries  hard  to  reconcile  the 
roundness  of  the  horizon  wdth  the  four  corners  of  the  earth  alluded 
to  in  Scriptiu-e.  His  statement  that  the  heaven  has  two  doors, 
east  and  west,  through  which  the  sun  passes,  also  looks  as  if  his 
point  of  view  was  much  the  same  as  that  of  the  patristic  wTiters. 


.      MEDIAEVAL  ASTRONOMY  105 

But  lie  was  the  last  prominent  author  of  whom  this  may  be  said, 
and  from  about  the  ninth  century  the  spherical  tigure  of  the 
earth  and  the  geocentric  system  of  planetary  motions  were  re- 
instated in  the  places  they  had  held  as  facts  ascertained  with 
certainty  among  Greek  philosophers  twelve  hundred  years  earlier. 
Among  the  writers  of  the  ninth  century  who  paid  any  atten- 
tion to  the  construction  of  the  Universe,  the  most  remarkable 
was  John  8cotus  Erigena.  In  his  great  work  De  Divisione  Naturae 
he  shows  that  he  is  acquainted  with  Chalcidius  and  Martianus 
Capella,  and  for  the  first  time  we  perceive  a  very  curious  influence 
which  these  rather  inferior  writers  exercised  throughout  the 
Middle  Ages.  In  the  fourth  century  b.  c.  Herakleides  of  Pontus, 
struck  with  the  fact  that  Mercury  and  Venus  are  never  seen  at 
a  great  distance  from  the  sun,  had  come  to  the  conclusion  that 
these  two  planets  move,  not  round  the  earth,  as  the  sun  and  the 
other  planets  were  supposed  to  do,  but  round  the  sun,  so  that  they 
are  sometimes  nearer  to  us  and  sometimes  farther  off  than  the 
sun.  But  this  idea  was  coldly  received  ;  it  was  quite  ignored  by 
Ptolemy  and  is  only  mentioned  by  Theon  of  Smyrna  and  Macrobius 
(without  alluding  to  Herakleides),  and  by  Martianus  Capella  and 
Chalcidius,  who  give  the  credit  to  Herakleides.  Theon  was  not 
known  in  the  Middle  Ages,  but  the  three  other  ^vl4ters  w^ere  held 
in  high  repute  ;  and  this  led  to  the  planetary  system  described 
by  them  being  known  to  many  mediaeval  writers,  though  to  most 
of  them  rather  confusedly,  as  if  they  did  not  quite  understand  it. 
Thus  Erigena  says  :  '  As  to  the  planets  which  move  round  the 
sun,  they  show  different  colours  according  to  the  quahty  of  the 
regions  which  they  traverse  ;  I  speak  of  Jupiter,  Mars,  Venus, 
and  Mercury,  which  incessantty  circle  round  the  sun,  as  Plato 
teaches  in  the  Timaeus.  When  these  planets  are  above  the  sun, 
they  show  us  clear  aspects,  they  look  red  when  they  are  below  it.' 
Plato  says  nothing  at  all  about  this  ;  but  perhaps  Erigena  had 
only  read  Chalcidius  and  assumed  that  what  he  said  was  also  to 
be  found  in  the  Timaeus.  Chalcidius  only  mentions  V^enus  as 
moving  round  the  sun,  but  as  he  had  already  described  the  apparent 
motions  of  the  two  inferior  planets,  he  probably  made  no  distinc- 
tion between  them.  M.  Duhem  seems  to  consider  it  highly 
creditable  to  Erigena  that  he  extended  the  system  of  Herakleides 
to  Mars  and  Jupiter,  which  nobody  else  did  for  fully  seven  hundred 
years,  till  Copernicus  and  Tycho  Brahe  let  all  the  five  planets 


10()  MKDIAKN'AI.   ASTllOXOMN 

move  roiiiid  (lie  Mill.  Kilt  witli  rc^jtrd  to  .liipitcr,  it  is  simply 
iibsiinl  to  im;iij;iii('  that  it  is  sometimes  above  tlic  siiii  (i.  e.  more 
distjuit  tluiii  the  Sim),  sometimes  below  it  (or  nearer).  As  to 
Mars,  that  planet  is  certainly  at  o|)position  nearer  to  the  earth 
than  the  siin  is,  but  there  is  no  reason  to  think  tiiat  the  astrono- 
mieal  know  ied^e  of  IOriji;ena  included  that  fact,  as  it  is  in  other 
directions  scanty  enoii<j;h  and  is  confined  to  carelessly  copied 
scraps  from  iiis  few  authoiities.  We  need  only  mention  his  state- 
ment that  half  the  (Mrcnmference  of  tiic  earth  is  e([iial  to  its 
diameter ! 

Probably  also  from  the  ninth  century  is  another  book  about 
the  l^ni verse,  Dc  inundi  caelef^tis  lerreslrisque  conslihUione  liher, 
formerly  ascribed  to  Bede,  but  quite  certainly  of  nmch  later  date, 
since  there  are  several  allusions  to  the  chronicles  of  (.*harlemagne. 
The  author  has  a  fair  knowledge  of  the  general  celestial  phenomena 
such  as  could  be  gathered  from  the  above-mentioned  sources,  but 
no  more.  It  is  interesting  to  see  that  he  favours  the  old  idea 
sometimes  met  with  among  the  Greeks,  that  the  planets  do  not 
really  travel  from  west  to  east,  but  from  east  to  west,  only  more 
slowly  than  the  sphere  of  the  fixed  stars  do  ;  so  that  Saturn, 
which  comes  to  the  meridian  about  eight  seconds  later  every 
night,  is  the  quickest  planet,  and  the  moon,  which  takes  fully 
three-quarters  of  an  hour  longer  than  the  fixed  stars  do,  is  the 
slowest — contrary  to  the  usual  idea,  that  Saturn,  which  takes 
29h  years  to  go  round  the  heavens  in  its  orbit,  is  the  slowest 
planet,  and  the  moon,  going  round  the  heavens  in  27  days,  is 
the  fastest.^  We  shall  see  present^  that  this  primitive  idea 
obtained  many  adherents  towards  the  end  of  the  Middle  Ages. 
As  to  Mercury  and  Venus,  the  writer's  opinion  is,  that  they  are 
sometimes  above  the  sun  and  sometimes  below  it,  as  it  is  recorded 
in  the  Historia  Caroli  that  Mercury  was  visible  for  nine  days  as 
a  spot  on  the  sun,  though  clouds  prevented  both  the  ingress  and 
the  egress  being  seen.  But  he  does  not  saj^  that  they  move  in 
orbits  round  the  sun.  The  writer  shows  himself  somewhat 
independent  of  his  authorities  by  adding  a  good  deal  of  astrology 
and  suggesting  various  rationalistic  theories  about  the  unavoid- 
able '  supercelestial  waters  '. 

Passing    over    the    extremeh'    elementary    Imago    Miindi    of 

1  See  for  instance  Plato,  2'imaeus,  pp.  38-9,  Leg.  821  sq. 


MEDfAEX'AL  ASTRONOMY 


107 


Fig.  1. 


doubtful  age  and  authorship,  we  must  next  mention  anotlier  work 
formerly  counted  among  the  writings  of  Bede,  entitled  Uepl 
8tSafewi/  ^ive  ehmentorum  philosophiae  libri  IV.  Tt  was  written 
by  William  of  Conches,  a  Norman  of  the  first  half  of  the  twelfth 
century.^  It  is  strange  that  it  should  ever  have  been  attributed 
to  Bede,  as  it  shows  a  freedom  of  thought  which  would  have  been 
impossible  early  in  the  eighth  century.  But  his  astronomical 
knowledge  is  often  confused  and  erroneous.  For  instance,  he 
knows  that  the  orbit  of  the  sun  is  a  circle  excentric  to  the  earth, 
but  he  imagines  that  the  great  heat  in  summer 
is  caused  by  the  sun  being  at  that  time  nearer 
to  the  earth  than  in  winter.  He  is  aware  of 
the  difference  of  opinion  among  the  ancients 
as  to  the  position  of  the  solar  orbit,  whether 
it  was  just  outside  the  lunar  orbit  (according 
to  the  P3rthagoreans,  Plato,  Eudoxus,  and 
Aristotle),  or  between  the  orbits  of  Venus 
and  Mars,  as  taught  by  Archimedes  and 
all  subsequent  writers,  including  Ptolemy. 
William  of  Conches  thinks  that  this  difference 
of  opinion  is  caused  by  the  fact  that  the  periods  of  Mercury, 
Venus,  and  the  sun  are  nearly  equal,  so  that  their  circles  must 
also  be  nearly  equal  and  therefore  are  not  contained  one  within 
the  other  but  intersect  each  other.  He  therefore  did  not  grasp 
the  real  meaning  of  the  system  of  Herakleides,  but  merely  conceived 
the  three  orbits  to  be  nearly  equal  in  size  with  their  centres  at 
short  distances  from  each  other  and  in  a  line  with  the  earth  ; 
and  his  description  agrees  with  a  diagram  given  in  an  anonymous 
manuscript  of  the  fourteenth  century,  copied  by  M.  Duhem. 

The  question  of  the  orbits  of  Mercury  and  Venus  continued 
to  crop  up  now  and  then,  as  long  as  Chalcidius  and  other  late 
authors  continued  to  be  considered  as  great  authorities  by  some 
writers  who  were  much  behind  their  own  time.  The  Rabbi 
Abraham  ben  Ezra  of  Toledo  (1119-75)  in  several  of  his  astro- 
logical writings,  which  were  printed  in  1507  at  Venice  in  a  Latin 
translation,  alludes  to  the  orbits  of  Mercury  and  Venus  being 
between  those  of  the  moon  and  the  sun  ;   but  in  one  place  he  says 

^  Two  manuscripts  in  the  Bibliotheque  Nationale  give  the  author's  name  as 
Willian\  of  Conches,  and  there  are  other  proofs  from  other  undoubted  writings 
of  his. 


108  .MI^:i)IAKVAL   ASTRONOMY 

that  tlio  two  ])lan('ts  iivc  soDK^time.s  abovc^  and  sometimeH  below 
the  Sim.  Tlic  same  oxprcssioM  is  used  in  tin;  following  century  by 
HartholoMuuMis  Anj2;licus  in  liis  encyclopaedic;  work  De  proprie- 
lalihus  rcnuH  (f.  1275).  Tlie  only  time  tliat  it  is  (;learly  and  dis- 
tinctly stated  that  Mercury  and  Vemis  traved  round  the  Sun  is 
in  an  astrological  manuscript  in  the  Bibliotheque  Nationale  of" 
the  year  1270  by  an  anonymous  astrologer  to  the  last  Latin 
Emperor  at  ('onstantinoi)le,  Baldwin  of  Oourtenay.  After  saying 
that  the  orbits  of  moon,  sun,  and  three  outer  jilanets  surround  the 
earth,  he  continues  :  '  Li  cercles  de  Venus  et  de  Mercure  ne 
I'environent  mie.  Ainz  corent  environ  le  Soloil  et  ont  lor  centre 
de  lor  cercles  el  cors  del  Soloil  ;  mes  Mercurius  a  le  centre  de  son 
cercle  el  milieu  del  cors  del  Soloil,  Venus  I'a  en  la  sourainete  del 
cors  del  Soloil ;  et  por  ce  sunt  il  dit  epicercle,  qu'il  n'environent 
mie  la  terre,  si  cum  j'ai  dit  desus  des  autres.'  The  author  might 
have  lived  hundreds  of  years  earlier ;  he  knows  nothing  of  Ptolemy 
or  of  the  Arab  writers  on  Ptolemaic  astronomy,  who  long  before 
the  time  he  wrote  had  become  known  in  the  west  of  Europe. 

For  while  Europe  had  been  content  to  pick  up  a  few  crumbs 
here  and  there,  the  East  had  been  feasting  on  the  intellectual 
repast  left  by  the  Greeks.  Works  on  Philosophy  and  Science  had 
been  translated  into  Arabic,  and  Mohammedan  authors  had 
written  text-books  founded  on  them  and  had  continued  the  work 
of  the  Greeks  in  Mathematics  and  Astronomy.  Arabic  authors 
began  to  be  known  in  the  West  from  about  the  year  1000 ;  Gerbert 
(Pope  Sylvester  II)  probably  wrote  a  book  on  the  astrolabe 
founded  on  Arabic  writings,  and  several  tracts  on  the  same  subject 
were  ^vritten  in  the  eleventh  and  twelfth  centuries  in  France, 
especially  at  Chartres,  at  that  time  the  principal  seat  of  learning 
there.  Translations  were  also  made  in  Italy  by  Plato  of  Tivoh  ; 
but  it  was  in  Spain,  where  science  was  still  under  the  protection 
of  powerful  Arabian  kings,  that  the  work  of  translation  was 
chiefly  carried  on.  The  first  translations  were  the  work  of  a  college 
of  interpreters  estabhshed  at  Toledo  ;  an  Arabian  scholar  trans- 
lating a  book  into  the  vulgar  tongue,  and  a  Spaniard  afterwards 
turning  this  into  Latin.  Ptolemaic  astronomy  became  kno^vn 
about  the  middle  of  the  twelfth  century  through  the  medium  of 
the  books  of  Al  Battani  and  Al  Fargani.  The  original  work  of 
Ptolemy,  the  Syntaxis  or  the  Almagest,  as  it  was  generally  called 
in  Latin  countries  from  a  corruption  of  part  of  the  Arabic  title 


MEDIAEVAL  ASTRONOMY  109 

{Al- fxeyia-TT)),  was  first  translated  about  tlie  same  time  by 
Gherardo  of  Cremona,  who  died  about  1184  at  the  age  of  73.  He 
seems  to  have  spent  most  of  his  Hfe  at  Toledo,  where  he  went  to 
find  the  Almagest.  Seeing  what  a  great  number  of  valuable  works 
in  Arabic  were  to  be  found  there,  he  learned  Arabic  and  is  said 
to  have  translated  no  less  than  seventy-four  different  works,  both 
by  Greek  and  Arabian  authors.  But  it  took  a  very  long  time 
before  people  could  be  found  capable  of  mastering  the  great  work 
of  Ptolemy. 

That  there  were  some  people  in  the  middle  of  the  twelfth 
century  anxious  to  spread  knowledge  of  astronomy  may  be  seen 
from  a  manuscript  in  the  Bibliotheque  Nationale,  examined  by 
M.  Duhem.  The  name  of  the  author  of  the  '  Tables  of  Marseilles ' 
is  not  known  ;  from  internal  evidence  it  appears  that  they  were 
prepared  about  the  year  1140.  The  author  says  that  students  of 
astronomy  were  compelled  to  have  recourse  to  worthless  writings 
going  under  the  name  of  Ptolemy  and  therefore  blindly  followed  ; 
that  the  heavens  were  never  examined,  and  that  any  phenomena 
not  agreeing  with  such  books  were  simply  denied.  He  therefore 
decided  to  transform  the  astronomical  tables  of  Al  Zarkali,  which 
were  computed  for  the  meridian  of  Toledo  and  adapted  to  Arab 
years,  so  as  to  arrange  them  for  the  meridian  of  his  native  city 
and  according  to  years  dated  from  the  birth  of  our  Lord.  This 
attempt  to  make  the  Toledo  tables  known  in  Latin  countries  did 
not  bear  fruit  immediately  ;  but  early  in  the  thirteenth  century 
imitations  of  the  tables  of  Marseilles  began  to  appear,  adapted  to 
the  meridians  of  Paris,  London,  Pisa,  and  Palermo,  even  for  that 
of  Constantinople,  at  that  time  ruled  by  Latin  Emperors.  The 
London  tables  date  from  the  year  1232  ;  the  author  mentions 
Ptolemy,  but  evidently  only  knows  his  work  by  name.^  This  is 
certainly  also  the  case  with  the  celebrated  little  book  on  the 
Sphere  by  John  of  Holywood  (Joh.  de  Sacrobosco),  written 
in  the  first  half  of  the  twelfth  century,  which  continued  to 
be  a  favourite  text-book  for  three  hundred  years  and  was 
repeatedly  printed.  He  only  had  his  wisdom  from  Al  Fargani 
and  Al  Battani,  for  he  copies  a  mistake  made  by  them  and  omits 
what  they  omit. 

^  Similar  tables,  founded  on  those  of  Al  Zarkali,  Avere  made  at  Montpellier 
towards  the  end  of  the  thirteenth  century  by  the  Jew  Jacob  ben  Makir,  generally 
called  Profatius. 


IK)  MKDIAKN'AI.   ASTIiOXOMV 

l»iit  ;i>(  I'oiiomiciil  hooks  wcit  taf  troiii  hciii^  the  oiil\'  oiu's 
( laiisiuittcd  lliroii^di  llic  Arabs.  Tlic  |iliil(>so|)l»it'<il  books  of 
Aristotle  and  of  his  coinmciitators,  as  well  as  iicoplatoiiic  and 
Arab  speculations,  also  crossed  the  Pyrenees.  At  Hist  they  were 
not  wcieomed  by  the  Chinch,  and  at  a  provincial  council  held 
at  Paris  in  1209  it  was  decreed  that  neither  Aristotle's  books  on 
natuial  philosophy  nor  coinmentaries  on  them  shoidd  be  read 
cither  publicly  or  privately  in  Paris.  In  1215  this  prohibition  was 
renewed  in  tiie  statutes  of  the  University  of  l*aris.  But  this 
resistance  wore  off  by  degrees  ;  better  translations  both  of 
Aristotle  and  of  Arab  astronomers  were  produced  by  Michael 
Scot  ;  while  Cuillanme  d'Auvergne,  Hishoj)  of  Paris  from  122S 
(died  124:8),  lent  his  ])0werful  aid  to  the  spreading  of  knowledge. 
He  was  a  prolific  \vriter,  and  was  the  first  to  make  serious  use  of 
Greek  and  Arab  philosoj)hy,  rejecting  what  was  contrary  to  the 
(Christian  faith  and  combining  the  rest  with  what  the  Churcli 
taught,  to  compose  a  philosoj)hicai  system  acceptable  to  the 
Christian  world.  Among  his  Avritings  was  a  treatise  De  Universo, 
which  stands  half  way  between  the  old  works  of  Isidore,  Bede, 
Pseudo-Bede,  Honorius,  and  the  later  encyclopaedias  of  Albertus 
Magnus  and  Vincent  of  Beauvais,  containing  more  philosophy  and 
less  theology  than  the  former.  But  his  opinions  on  celestial 
motions  are  wevy  confused.  For  instance,  he  thinks  that  one  can 
'  by  means  of  astronomical  instruments  and  certain  geometrical 
instruments  '  determine  the  distance  of  the  earth  from  each  of  the 
fixed  stars  and  from  each  of  the  planets.  The  waters  above  the 
mo^4ng  spheres  are  neither  fluid  nor  in  a  state  of  vapour  ;  they 
form  an  ethereal  mass,  perfectly  transparent  and  immobile, 
separating  those  spheres  from  the  Empyrean. 

The  introduction  of  Aristotelian  natural  philosophy  in  the 
Universities  of  Paris  and  Oxford  brought  about  a  prolonged  strife 
between  Aristotelian  ideas  of  the  construction  of  the  Universe 
and  the  Ptolemaic  system  of  the  world  ;  or  rather  a  revival  in 
France  and  England  of  an  old  dispute  which  had  existed  first  in 
the  Hellenistic  and  then  in  the  Mohammedan  world.  Aristotle 
had  adopted  the  '  homocentric  spheres  '  of  Eudoxus  to  account 
for  the  motions  of  the  planets  ;  but  though  this  would  to  some 
extent  explain  the  chief  irregularities  in  these  motions,  continued 
observations  soon  showed  that  the  system  was  insufficient  to 
'  save  the  phenomena  ',  particularly  as  it  could  not  account  for 


MEDIAEVAL  ASTRONOMY  111 

the  variable  distance  of  a  planet  from  the  earth.  A  totally  different 
system  had  therefore  been  developed  at  Alexandria  in  the  course 
of  nearly  four  hundred  years,  until  it  was  completed  by  Ptolemy. 
According  to  this,  a  planet  moved  on  the  circumference  of  a  circle 
(the  epicycle),  the  centre  of  which  travelled  on  a  larger  circle  (the 
excentric  or  deferent)  the  centre  of  which  was  at  some  distance 
from  the  earth  ;  but  in  such  a  manner  that  its  motion  was  uni- 
form, not  with  regard  to  the  centre  of  the  deferent,  but  as  seen 
from  another  point,  the  punctum  aequans.  The  centre  of  the 
deferent  was  midway  between  that  point  and  the  earth.  Further 
complications  had  to  be  introduced  to  account  for  the  motion 
in  latitude  of  the  planets.  From  a  mathematical  point  of  view 
this  system  was  perfect,  as  it  really  could  '  save  the  phenomena  ', 
that  is,  represent  the  actually  observed  motions  with  an  accuracy 
nearly  corresponding  to  that  attainable  by  the  crude  instruments 
then  in  use.  But  it  was  totally  at  variance  with  Aristotelian 
Physics,  the  adhere^its  of  which  viewed  the  movements  around 
points  outside  the  centre  of  the  world  with  extreme  disfavour. 
Long  before  Ptolemy's  time  attempts  had  therefore  been  made  to 
reconcile  the  two  systems.  This  was  simple  enough,  as  long  as 
the  deferent  was  assumed  concentric  with  the  earth.  The  epicycle 
might  then  be  conceived  to  be  the  equator  of  a  solid  sphere,  rolling 
between  two  solid  concentric  spheres.  This  idea  is  described  by 
Theon  of  Smyrna  (soon  after  a.  d.  100),  but  it  must  be  much 
older.  It  became  untenable,  as  soon  as  the  deferents  became 
excentric  circles.  In  the  Syntaxis  Ptolemy  merely  alludes  to 
planetary  spheres  when  describing  the  order  of  tl^e  various  orbits 
(ix.  1)  ;  and  his  attitude  with  regard  to  the  equivalence  of  the 
epicyclic  and  excentric  theories  shows  that  he  had  broken  with 
the  idea  described  by  Theon  and  did  not  attribute  any  reality 
to  the  multiple  motions  of  the  Syntaxis,  but  merely  considered 
them  as  geometrical  means  of  representing  the  real  motions.  But 
in  a  later  work,  Hypotheses  of  the  Planets,  or  rather  in  the  second 
book  of  it,  Ptolemy's  ideas  are  quite  different.^  Here  he  proposes 
to  do  for  the  complicated  theories  of  the  Syntaxis  what  the  system 
of  Theon  did  for  the  simple  epicyclic  motion,  producing  not  a  mere 
model  but  a  real  representation  of  the  constitution  of  the  universe, 

^  The  Greek  original  is  lost,  but  a  translation  into  Arabic  has  been  preserved, 
from  which  a  German  translation  was  printed  in  1907  [Cla^idii  Ptolemaei  Ojiera, 
ed.  Heiberg,  T.  ii). 


112  MKDIAKVAI.   ASTIIONOMV 

as  real  as  tliat  described  in  Aristotle's  Mela  physic.^.  Tl^e  epicycle- 
spliere  now  fits  between  two  excentric  sj)lierieal  surfaees  whicli 
toueh  two  otiier  surfaces  (an  iinier  and  an  <jut(T  one),  in  the 
common  centre  of  wliieh  the  eartli  is  situated.  This  system  of 
tlie  world  docs  not  seem  to  iiave  been  a  success  ;  iji  the  neoplatonic 
schools  the  theories  of  th(^  SyiUaxis  appear  to  have  been  more 
valued,  although  the  old  Platonic  and  Aristotelian  dogma,  that 
every  celestial  motion  must  be  circular  and  uniform  round  the 
centre  of  the  earth,  still  found  partisans. 

Towards  the  end  of  the  eighth  century  Mohammedan  nations 
began  to  become  acquainted  with  Alexandrian  astronomy,  in  the 
first  instance  through  the  medium  of  northern  India,  where 
a  knowledge  of  Greek  science  had  spread  in  the  first  couple  of 
centuries  after  the  conquests  of  Alexander  the  Great.^  The 
system  of  spheres  seems  to  have  appealed  strongly  to  Eastern 
minds  ;  and  throughout  the  time  when  astronomy  continued  to 
be  successfully  cultivated  in  the  Mohammedan  world  we  find  that 
various  combinations  of  spheres  were  proposed  by  people  who 
could  not  be  satisfied  with  the  Ptolemaic  system  of  circles,  while 
the  latter  was  accepted  and  used  by  professional  astronomers. 
The  first  to  describe  the  spheres  was  Tabit  ben  Korrah,  in  the 
second  half  of  the  ninth  century.  He  seems  to  have  been  the 
first  to  fix  the  number  of  spheres  at  nine,  and  he  was  followed 
by  the  '  Brethren  of  Purity '  in  the  tenth  century  and  by  Ibn 
al  Haitham  (c.  a.  d.  1000)."  The  necessity  of  introducing  a  ninth 
sphere  above  the  eighth  sphere  (the  sphere  of  the  fixed  stars)  was 
due  to  the  imaginary  phenomenon  of  trepidation  or  oscillatory 
movement  of  the  equinoxes.  This  dates  back  to  the  time  before 
Ptolemy,  but  he  quite  ignored  it  and  taught  that  the  Precession  of 
the  Equinoxes  is  uniformly  progressive,  while  Tabit  (though  speak- 
ing with  a  certain  reservation)  accepted  the  phenomenon  of 
trepidation  as  real.  The  Arabian  combinations  of  spheres  were 
mainly  borrowed  from  Ptolemy,  though  with  modifications.     It 

^  From  what  M.  Duhem  says  (vol.  ii,  p.  213)  it  looks  as  if  he  thought  that 
Arabian  astronomy  was  founded  on  indigenous  Indian  knowledge.  But  it  is 
quite  certain  that  the  Indians  derived  all  their  knowledge  of  planetary  motion 
from  the  Greeks.  See  J.  Burgess,  in  Journal  of  the  R.  Asiatic  Society,  October 
1893,  pp.  746  sq.,  and  Dreyer,  Hist,  of  the  Planetary  Systems  (Cambridge,  1906), 
pp.  240  sqq. 

-  Known  in  the  West  as  Alhazen,  author  of  a  celebrated  book  on  Optics. 


MEDIAEVAL  ASTRONOMY  113 

was  particularly  in  Spain  that  the  opposition  to  the  Ptolemaic 
system  of  excentrics  and  epicycles  came  to  the  front,  being 
intimately  connected  with  the  rapid  rise  of  Aristotelian  philosophy 
in  that  country  in  the  twelfth  century,  which  culminated  in  the 
work  of  Averroes,  the  greatest  philosopher  of  Islam.  An  ingenious 
attempt  at  reviving  the  principle  of  homocentric  spheres  in 
a  perfectly  novel  manner  was  made  by  the  astronomer  Al  Bitrugi 
(Alpetragius),  though  the  leading  idea  was  probably  due  to  the 
philosopher  Ibn  Tofeil. 

This  system  of  homocentric  spheres  differs  from  that  of 
Eudoxus  and  Aristotle  by  assuming  that  the  prime  mover  (the 
ninth  sphere)  everywhere  produces  only  a  motion  from  east  to 
west,  the  independent  motion  of  the  planets  from  west  to  east 
being  rejected.  We  have  already  mentioned  that  this  was  a  very 
old  idea  which  had  been  revived  in  Europe  by  Pseudo-Bede. 
But  Al  Betrugi  saw  that  this  was  not  sufficient,  as  not  only  is  the 
pole  of  the  ecliptic  different  from  that  of  the  equator,  but  the 
planets  do  not  even  keep  at  the  same  distance  from  the  pole  of 
the  ecliptic  but  have  each  their  motion  in  latitude  as  well  as 
a  variable  velocity  in  longitude,  all  of  which  had  to  be  accounted 
for.  This  is  done  by  letting  the  pole  of  each  planet's  orbit  describe 
a  small  circle  round  a  mean  position  (the  pole  of  the  ecliptic)  in 
the  synodic  period  of  the  planet.^  But  the  system  was  not  worked 
out  in  detail ;  and  only  philosophers  who  wanted  nothing  more 
than  a  representation  of  the  principal  phenomena  could  be  satis- 
fied with  it.  In  the  eyes  of  astronomers  it  had  many  faults,  the 
greatest  being  (as  in  the  case  of  the  system  of  Eudoxus)  that  it 
assumed  a  planet  to  be  always  at  the  same  distance  from  the 
earth. 

When  Michael  Scot  about  the  year  1230  had  produced  his 
translations,  the  attacks  of  Averroes  and  Al  Betrugi  on  the 
epicyclic  system  spread  rapidly  among  the  Scholastics.  Though 
people  who  only  desired  to  account  for  the  apparent  motions  of 
the  planets  as  seen  projected  on  the  celestial  vault  continued  to 
follow  the  rules  of  Ptolemy,  philosophers  were  greatly  concerned 

1  The  account  given  by  M.  Duhem  of  this  historically  important  system  is 
most  unsatisfactory.  For  further  details  see  Hist,  of  the  Planetary  Systems, 
p.  265,  a  book  which  seems  to  be  unknowTi  to  M.  Duhem.  It  is  curious  to  see 
how  astronomical  historians  have  fought  shy  of  explaining  the  system  ;  see  e.  g. 
Delambre,  Hist,  de  VAsir.  du  Moyen  Age,  p.  174. 


114  MKDI AKA'AL   ASTRONOMY 

al)()iit.  the  emit liulict ion  hctwccM  Aristotle  and  iHcjIciiiy.  During 
ilic  whole  of  the  Hccoiid  lialf  of  tlic:  thirteenth  century  thi«  a^itate^ 
the  two  rival  orders  of  Dominicans  and  Kran(;iscans,  wlio  dominated 
the  I'lii  versify  of  I*aris.  Amon^  the  former  Albert  us  Magnus  was 
at  tirst  the  most  i>rominent.  Hv  was  nmcli  attracted  by  the 
system  of  Al  I^itrugi,  whicli  he  thought  was  very  simple,  because 
he  ignored  the  small  circles  and  tluTcby  made  it  (juitc^  useless. 
It  was  in  this  sim|)lified  form  oidy  that  the  system  continued  to 
be  known  to  most  of  the  Scholastics,  wliich  sufficiently  characterizes 
their  superficial  knowledge  of  celestial  motions.  Yet  Albert  was 
quite  aware  of  the  fatal  objection  to  every  form  of  homocentric 
system,  and  he  fijially  declared  for  Ptolemy.  The  same  was  the 
case  with  his  disciple  Thomas  Aquinas,  For  the  simplified  system 
of  Al  Bitrugi  he  substituted  the  idea  that  celestial  bodies  are 
animated  by  two  movements  ;  the  first  is  a  uniform  rotation 
from  east  to  west,  a  principle  of  eternal  duration  ;  the  second  is 
a  rotation  from  west  to  east  round  the  poles  of  the  ecliptic,  a 
principle  of  generation  and  transformation,  a  movement  in  which 
the  different  orbs  take  part  to  a  lesser  extent  the  more  noble  they 
are.  Like  Albert  he  ends  by  abandoning  Averroes  for  Ptolemy, 
chiefly  on  account  of  the  change  of  distance. 

If  we  turn  to  the  Franciscans  we  are  met  with  more  hesitation 
as  to  the  choice  between  the  rival  theories.  Bonaventura,  the 
Doctor  seraphicus,  does  not  seem  to  have  devoted  much  attention 
to  astronomy.  According  to  him  there  is  a  ninth  heaven,  the 
aqueous  one,  which  is  the  primum  mobile  ;  some  philosophers 
have  perceived  that  the  firmament  has  a  proper  motion  of  1°  in 
a  hundred  years,^  but  whether  this  is  true  or  not  it  is  certain  that 
Doctors  of  Theology  admit  that  there  is  a  moving  heaven  without 
stars. 

But  in  Roger  Bacon  w^e  meet  at  last  with  a  man  who  was 
thoroughly  acquainted  with  the  astronomical  wTitings  both  of 
Greeks  and  Arabs.  At  Oxford  he  was  under  the  influence  of 
Robert  Grosse-Teste,  afterwards  Bishop  of  Lincoln,  w^ho  had 
devoted  some  attention  to  astronomy  and  was  a  follower  of 
Ptolemy,  except  when  he  wanted  to  be  a  metaphysician  and  had 
to  follow  Al  Bitrugi.  But  it  w^as  not  till  Bacon  went  to  Paris 
(about  1235)  that  he  was  able  to  study  scientific  problems 
seriously.  M.  Duhem  gives  a  lengthy  account  of  a  manuscript 
^  The  amount  of  precession  according  to  Ptolemy. 


MEDIAEVAL  ASTRONOMY  115 

in  the  municiy)al  library  of  Amiens,  containing  several  series  of 
questions  on  the  Physics  and  Metaphysics  of  xAristotle.  They  are 
probably  written  by  pupils  of  Bacon  at  Paris,  at  latest  about 
the  year  1250.  The  questions  on  the  Metaphysics  must  be  the 
earliest ;  the  teacher  does  not  appear  to  know  Ptolemy's  works, 
and  only  to  have  heard  of  Al  Bitrugi.  The  questions  on  Aristotle's 
Physics  show  more  knowledge,  especially  of  the  system  of  Eudoxus 
and  of  Precession.  The  subsequent  writings  of  Bacon  show  how 
he  persevered  in  his  study  of  cosmology  and  astronomy  ;  but  he 
continues  all  his  life  to  hesitate 
between  the  two  systems  of  the 
world.  He  studies  the  Almagest, 
he  borrows  from  Al  Fargani  what 
he  says  about  the  dimensions  of 
t^e  planets  and  of  their  orbits  ; 
on  the  other  hand  he  makes  him- 
self thoroughly  acquainted  with 
the  theory  of  Al  Bitrugi,  the  de- 
tails of  which  hitherto  had  scared 
readers  in  France.  In  his  Opus 
tertium  he  gives  a  carefully  written 
summary  of  that  theory,  and  then  yw,.  2 

gives    an    account    of   the    system        1.  Epicycle  Sphere.     2.  Excentric  Sphere. 
of  solid  orbs  described  by  Ptolemy   3.  The  Surrounding  Sphere.    4.  Complement 
in    his    Hypotheses    and    taken    up   of  Surrounding  Sphere       5.  The  Earth.      6. 
•^-^  ^     Centre  of  Excentric  Sphere. 

by  Ibn  al  Haitham.  Bacon  ac- 
knowledges that  it  does  away  with  many  of  the  objections  formu- 
lated by  Averroes  against  the  epicyclic  system,  but  he  thinks  that 
there  are  too  many  questionable  hypotheses  in  it.  His  main  objec- 
tion is,  that  the  two  bodies  between  which  each  deferent  is  com- 
prised have  in  their  various  parts  different  thickness,^  but  this 
cannot  be  the  case  in  celestial  bodies  on  account  of  their  simple  and 
homogeneous  nature.  He  also  thinks  that  a  celestial  body  cannot 
be  supposed  to  be  devoid  of  all  motion.  Other  objections  made 
by  Bacon  seem  to  show  that  he  cannot  have  been  acquainted 
with  the  second  book  of  Ptolemy's  Hypotheses,  the  Greek  original 
of  which  was  probably  lost  before  that  time  ;  and  that  he  only 
had  before  him  an  incomplete  resume  of  the  systems  of  spheres 

^  Compare   the   diagram   in   the   History  of  the  Planetary  Systems,  p.  259 
(reproduced  above),  the  surrounding  sphere  and  its  complement. 


IKi  MKI)I\K\AL   ASTKOXO.MV 

ot  I'lok'iny  and  llm  al  Haitliani.'  Bacon  tlicrclorc  never 
reaehod  any  eoiielusion  as  to  wliicli  system  of  tlie  world  was  the 
true  one. 

But  a  younj^er  eonteniporary  of  I-Jaeon  amon^  the  Kraneiseans, 
Bernard  of  N'erdun,  made  up  his  mind  to  break  with  Aristotk;  and 
Al  Bitrugi.  In  a  Tractatvs  oplimus  super  lotain  Aslroloqiaw,  of 
which  two  manuscripts  are  known  to  exist,  and  which  shows 
famiHarity  with  Bacon's  works,  he  begins  by  counting  up  tlie 
facts  which  must  be  explained  :  the  change  of  velocity  of  the 
planets  ;  the  variability  of  the  moon's  diameter,  the  moon  being 
more  or  less  completely  eclipsed  even  in  the  same  point  of  the 
ecliptic  ;  the  upper  planets  (particularly  Mars)  being  brightest 
at  opposition  to  the  sun,  while  Mercury  and  Venus  are  of  greater 
brightness  after  leaving  the  sun  and  moving  eastward  than  when 
they  leave  it  to  move  westward.  All  these  facts  distinctly  con- 
tradict all  homocentric  theories,  and  Bernard  therefore  finally 
rejects  the  system  of  Al  Bitrugi,  with  which  he  shows  that  he  is 
well  acquainted.  In  the  system  of  spheres  of  Ptolemy  or  its 
imitation  by  Ibn  al  Haitham  he  sees  the  means  of  shielding  the 
Ptolemaic  system  from  Aristotelian  attacks  ;  and  as  the  theory 
of  excentrics  and  epicycles  is  the  only  one  which  is  able  to  produce 
tables  of  planetary  motions  and  '  save  the  phenomena  ',  Bernard 
does  not  hesitate  to  proclaim  it  as  the  true  system.  The  above- 
mentioned  objection  raised  by  Bacon  he  brushes  aside  by  saying 
that  the  surrounding  spheres,  &c,,  are  not  proper  celestial  bodies, 
but  like  those  parts  of  a  cithern  which  do  not  give  any  sound. 

This  treatise  by  Bernard  of  Verdun  seems,  at  least  for  the 
University  of  Paris,  to  mark  the  epoch  when  the  Ptolemaic  system 
began  to  reign  absolutely  among  students  of  astronomy  ;  the 
adherents  of  Al  Betrugi  had  to  give  up  the  struggle.  There  are 
various  other  tracts  in  existence  from  the  time  around  the  year 
1300  which  confirm  this  result,  while  they  show  at  the  same  time 
that  the  question  about  the  precession  of  the  equinoxes,  whether 
it  was  a  steady  progressive  motion  or  only  an  oscillation,  was 
still  unsettled,  which  involved  uncertainty  as  to  the  number 
of  spheres  above  those  of  the  planets.  The  Alfonsine  Tables, 
prepared  under  the  direction  of  King  Alfonso  X  of  Castille,  were 
finished  about  1270,  but  thej'  were  probably  not  at  once  issued  to 

1  The  fact  that  he  calls  the  system  Ymaginatio  modernorum  also  points  to  his 
only  having  known  an  Arabic  account  of  it. 


MEDIAEVAL  ASTRONOMY  117 

the  public.  At  any  rate  it  is  certain  that  tliey  were  not  known  at 
Paris  until  towards  the  end  of  the  thirteenth  century,  the  tables 
of  Al  Zarkali  (the  tables  of  Toledo)  being  still  in  use  there.  The 
time  had  come  however  when  some  people  among  the  Christian 
nations  had  begun  in  a  small  way  to  occupy  themselves  with 
practical  astronomy,  instead  of  merely  speculating  whether  there 
were  nine  or  ten  heavens,  or  considering  whether  an  astronomer  or 
a  philosopher  was  the  best  guide  among  the  stars.  There  is  a  codex 
in  the  Bibliotheque  Nationale  which  contains  several  tracts  from 
the  end  of  the  thirteenth  and  the  beginning  of  the  fourteenth 
century  bearing  witness  to  this  change  of  study.  Among  these 
are  two  by  Guillaume  de  St.  Cloud,  one  being  an  Almanac  for 
twenty  years  from  1292,  the  other  a  Calendar,  the  date  of  which 
is  1296,  which  gives  the  time  of  entry  of  the  sun  into  each  of  the 
twelve  signs  for  two  hundred  years  before  and  after  the  year 
1296.  At  the  beginning  of  the  Almanac  it  is  stated  that  the 
tables  of  Ptolemy  of  Alexandria,  Tolosa  (?),  and  Toledo  do  not 
agree  with  observations  ;  there  is  no  mention  of  the  Alfonsine 
Tables.  From  observed  solstitial  altitudes  of  the  sun  in  1290  the 
obUquity  of  the  ecliptic  is  found  to  be  23°  34'  and  the  latitude  of 
Paris  48°  50'.  Guillaume  also  determines  the  time  of  the  spring 
equinox  of  1290  (March  12,  16'')  and  corrects  the  errors  of  the 
Tables  of  Tolosa  by  the  simple  expedient  of  correcting  the  mean 
motions  thus:  of  Saturn  by  —  1°  15',  of  Jupiter  by  +1°,  of  Mars 
by  —  3°.^  M.  Duhem  does  not  explain  what  the  Tables  of  Tolosa 
are,  but  a  fragment  of  a  tract  by  Guillaume  de  St.  Cloud  quoted 
by  Nicolaus  de  Cusa  gives  the  clue  to  this  riddle.'-  The  fragment 
gives  the  errors  of  the  Alfonsine  Tables  for  the  three  planets,  and 
the  amounts  are  exactly  the  same  as  those  given  in  the  codex 
as  the  errors  of  the  Tables  of  Tolosa.  This  shows  that  the  Alfonsine 
Tables  had  become  known  at  Paris  by  the  year  1292. 

The  same  interesting  codex  also  contains  a  tract  by  Johannes 
de  Muris,  a  native  of  Normandy.  He  quotes  the  determination  of 
the  equinox  of  1290  and  describes  how  he  repeated  it  at  Evreux  in 
1318  (March  12,  16''  40"')  ;  he  says  this  agrees  with  King  Alfonso's 
and  Guillaume  de  St.  Cloud's  observations.  Joh.  de  Muris  and 
Firmin  de  Belleval  wrote  a  report  on  the  reform  of  the  calendar, 
by  order  of  the  Pope,  which  if  adopted  would  have  settled  this 
question  more  than  two  hundred  years  before  the  time  when  the 
1  Duhem,  T.  iv,  p.  18.  ^  jbid..  p.  23. 

2391  T 


lis  MEDIAEVAL   ASTRONOMY 

Gregorian  ictonn  was  actually  carried  out.     Firinin  wrote;  a  little 
book  on  M('troi()lon;y  which  was  ])rinte(l  at  V^eni(;e  in  14!Sr>.' 

Another  astronomer  of  the  first  half  of  the  fourteenth  century 
who  must  not  be  passed  over  here,  though  not  coiniect(Kl  with 
l*aris,  was  a  Jew,  Levi  ben  Gersoji  of  Avignon,  who  died  in  1344. 
He  wrote  against  the  system  of  Al  Betrugi  and  (what  is  more 
important)  he  invented  (or  at  least  introduced)  the  instrument 
known  as  Haculus  Jacobi  or  Cross  Staff  for  measuring  the  angular 
<listance  between  two  stars  ;  and  better  still,  he  aj)plied  a  diagonal 
scale  to  it.  The  latter  invention  (not  mentioned  by  M.  Duhem) 
appears  to  have  remained  unnoticed  for  about  two  hundred  years.^ 
Practical  astronomy  was  also  cultivated  by  Johannes  de  Lineriis 
(Jean  de  Linieres),  from  whose  hand  there  are  several  manuscript 
treatises  in  the  Bibliotheque  Nationale,  among  them  a  guide  to 
the  use  of  the  Alfonsine  Tables  and  Theorica  Planetarum,  anno 
Christi  1335.  The  latter  is  an  account  of  the  Ptolemaic  System 
from  the  Almagest  (without  spheres)  ;  there  is  a  chapter  on  the 
motion  of  the  eighth  and  ninth  spheres,  in  which  it  is  shown 
that  Tabit's  theory  of  oscillation  must  be  rejected,  as  the  equinox 
has  now  receded  more  than  that  theory  allows ;  the  author  is  inclined 
to  adopt  the  theory  proposed  by  Alfonso  X  combining  progressive 
and  oscillatory  motion.  Jean  de  Linieres  also  produced  a  catalogue 
of  positions  of  forty-seven  stars,  the  first  attempt  in  Europe  to 
correct  some  of  the  star-places  given  in  Ptolemy's  Catalogue.^ 

^  Opusculum  repertorii  pronosticon  in  mutationes  aeris.  M.  Duhem  (T.  iv, 
p.  42)  says  that  according  to  a  manuscript  copy  in  the  Bibl.  Xat.  there  was  an 
interval  of  68  years  between  the  Alfonsine  Tables  and  the  epoch  of  certain  tables  ; 
this  gives  the  date  of  the  book  1252  +  68  =  1320.  The  sentence  quoted  occurs  in 
the  printed  book  on  f.  12v  at  the  foot,  but  the  interval  is  86,  which  gives  1338. 
The  context  shows  that  86  is  a  misprint ;  yet  compare  f.  3v,  where  1338  is 
given  as  the  epoch  of  some  star-places  brought  up  from  Ptolemy's  catalogue. 

2  M.  Duhem  (T.  iv,  p.  40)  says  that  the  use  of  the  baculus  was  introduced 
among  Portuguese  navigators  by  the  German  scientist  Martin  Behaim  towards 
the  end  of  the  fifteenth  century.  But  it  has  been  conclusively  shown  by  Joaquim 
Bensaude  {U Astronomie  nautique  au  Portugal  a.  Vepoque  des  grandes  decouvertes, 
Berne,  1912)  that  the  baculus  was  known  in  Portugal  long  before  the  time  of 
Behaim,  to  whom  and  his  compatriots  the  Portuguese  owed  nothing.  M.  Duhem 
quotes  this  book  in  a  footnote  without  noticing  that  it  demolishes  what  he  has 
just  stated  in  the  text. 

^  See  a  paper  by  G.  Bigourdan  in  the  Comptes  rendus,  December  1915  and 
January  1916.  The  catalogue  was  printed  in  Riccioli's  Astronomia  Reformata, 
i,  p.  216. 


i 


MEDIAEVAL  ASTRONOMY  119 

Other  manuscripts  from  the  fourteenth  century  show  that 
various  teachers  at  Paris  continued  to  expound  the  Ptolemaic 
system,  with  or  without  spheres.  At  the  beginning  of  the  century 
Aegidius,  a  native  of  Rome,  ^vrote  a  Hexaemeron  (printed  several 
times  in  the  sixteenth  century)  in  which  he  proposes  to  let  the 
epicycle-sphere  He,  not  between  two  spheres,  but  in  a  cavity  in 
the  celestial  matter  of  the  form  of  an  anchor  ring.  Some  of  these 
writers  had  not  a  very  clear  idea  of  what  they  wrote  about ;  e.  g. 
Albert  of  Saxony  in  a  Commentary  to  Aristotle's  De  Caelo  (also 
printed  several  times)  says  that  the  moon  does  not  move  in  an 
epicycle  ;  for  if  it  did,  the  figure  of  a  man  in  the  moon  carrying 
af  bundle  of  sticks  would  sometimes  be  seen  upside  down !  He 
means  of  course  that  the  moon  would  not  always  turn  the  same 
side  to  the  earth. 

Though  M.  Duhem  several  times  alludes  to  the  Alfonsine 
Tables,  he  has  evidently  not  examined  any  codices  of  them. 
He  has  thus  missed  the  interesting  fact,  that  the  tables  first 
published  at  Toledo  about  the  year  1270  were  totally '  different 
from  those  first  printed  in  1483.  The  latter  were  a  modification 
of  the  original  tables  made  at  Paris,  probably  by  Jean  de  Linieres. 
At  Oxford,  where  there  seems  to  have  been  a  good  deal  of  interest 
taken  in  astronomy  from  the  beginning  of  the  fourteenth  century, 
the  tables  in  their  original  form  remained  in  use  longer  than 
anywhere  else.^ 

While  science  had  thus  begun  to  be  earnestly  cultivated  in  France 
and  England,  Italy  had  remained  behind.  Though  Gherardo  of 
Cremona  had  translated  the  Almagest  about  the  year  1175,  more 
than  a  century  passed  before  a  single  Italian  studied  it,  while 
the  text-book  of  Al  Fargani  was  the  usual  guide.  But  it  is  remark- 
able how  badly  even  that  book  was  understood,  the  most  extra- 
ordinary blunders  being  made  by  the  best  of  the  Italian  writers. 
Dante  is  an  honourable  exception  ;  there  are  no  blunders  in  his 
cosmological  ideas,  neither  in  the  Divine  Comedy  nor  in  the 
Convivio.  The  latter  shows  the  craze  for  astrology  which  pre- 
vailed in  Italy,  while  this  branch  of  learning  was  at  Paris  always 
of  secondary  importance.  The  Italians  took  no  part  in  the  dispute 
whether  a  system  of  Physics  deduced  from  peripatetic  principles 

^  Cf .  Dreyer,  '  On  the  original  form  of  the  Alfonsine  Tables ',  in  Monthly 
Notices  of  the  Royal  Astronomical  Society,  vol.  Ixxx,  pp.  243-62. 


120  Mb:DIAK\'AL   A.s'i'IlOXOM Y 

or  a  science  const nieted  to  ajzice  with  oh.sorvcd  facts  should 
coiKjiier.  Only  l'eliii>  de  Al)an(>  (abont  l.'{()(>)  alludes  to  it.  hut 
the  dis|)ute  had  hceii  .settled  before  lie  went  to  Paris.  Ill  the 
Universities  ol  Spain  and  Portuf^al  the  fight  did  not  hejrin  til! 
the  middle  ol  the  lifteenth  century  and  lasted  about  a  hundred 
years,  during  wliich  time  objections  were  raised  which  liad  been 
demolished  elsewhere  long  before.^ 

The  second  half  of  M.  T)uh(!in's  fouith  Nolume  and  the  whole 
of  the  fifth  deal  with  Arabian  and  Scholastic  Philosophy.  His 
account  of  mediaeval  cosmology  and  astronomy  reaches  to  the 
end  of  the  fourteenth  century,  except  that  it  does  not  deal  with 
any  English  writers  after  Roger  Bacon.  The  revival  of  astronomy 
in  Europe  has  hitherto  been  sujjposed  to  date  from  the  middle 
of  the  fifteenth  century,  and  to  have  commenced  with  the  labours 
of  Cusa,  Peurbach,  and  Regiomontanus  in  Germany.  We  know 
now  from  the  researches  of  M.  Duhem  that  the  revival  began  in 
France  fully  a  hundred  years  earlier,  while  tlie  studies  of  M.  Ben- 
saude  have  shown  that  the  scientific  light  s])read  by  the  Arabs  in 
Spain  and  Portugal  had  never  been  put  out,  so  that  the  navigators 
who  found  the  way  to  the  Indies  and  to  the  New  World  had 
nothing  to  learn  from  German  astronomers.  We  shall  look  forward 
with  great  interest  to  the  j^romised  sixth  volume  of  M.  Duhem, 
while  deeply  regretting  that  his  early  death  should  have  pre- 
vented him  from  completing  this  vast  monument  of  learning  and 
perseverance. 

^  In  the  south  of  France  a  last  attempt  to  substitute  spheres  for  epicycles  and 
excentrics  was  in  the  fourteenth  century  made  by  Levi  ben  Gerson  in  his  work 
Milchamot  Adona'i,  of  which  an  account  was  published  by  Carlebach  in  1910 
(Duhem,  v,  pp.  201  sqq.). 


ROGER  BACON  AND  THE   STATE  OF  SCIENCE 
IN  THE  THIRTEENTH  CENTURY 

By  Robert  Steele 

The  real  value  of  a  man's  work  can  only  be  estimated  with 
any  approach  to  accuracy  when  it  is  seen  against  the  background 
of  the  intellectual  hfe  of  his  time  :  when  his  contribution  to  the 
world's  thought  is  confronted  with  the  ideas  of  his  contemporaries, 
whether  they  run  together  in  harmony  or  diverge  into  independent 
ways  of  development.  The  position  of  Roger  Bacon  in  the  history 
of  science  depends  not  only  on  the  actual  contributions  to  tlie 
stock  of  knowledge  he  made,  but  also,  and  more  especially,  on 
his  mode  of  approach  to  the  problems  of  his  age,  and  on  the 
foresight  with  which  he  selected  the  objects  of  his  study. 

The  story  of  his  life  has  often  been  told,  and  is  tolerably 
familiar  to  most  readers.  Born  about  1214,  the  year  before  Magna 
Carta,  he  first  appears  in  history,  if  it  be  indeed  the  same,  as 
a  young  clerk  at  the  court  of  Henry  III  in  1233.  Soon  afterwards 
he  left  Oxford  and  went  to  Paris,  at  least  for  a  time,  before  1236. 
He  seems  to  have  travelled  in  Italy,  dedicated  a  book  to  Pope 
Innocent  IV,  returned  to  Paris,  lectured  there  as  a  Master  in  the 
University,  and  returned  to  Oxford  about  1251.  He  joined  the 
Franciscans  about  1254,  and  towards  1257  was  sent  to  their  Paris 
convent,  where  he  remained  ten  years.  In  1266  he  received  the 
commands  of  Pope  Clement  IV  to  send  him  a  fair  copy  of  his 
works,  but  Clement's  death  in  1268  frustrated  any  hopes  from 
him,  and  in  1278  he  was  condemned  for  teaching  '  suspected 
novelties  '  and,  tradition  says,  imprisoned  till  1292,  in  which  year 
he  composed  his  last  work,  and  shortly  afterwards  died. 

The  public  life  of  Roger  Bacon,  then,  extends  from  1236  to 
1272,  the  middle  years  of  the  great  thirteenth  century,  almost 
the  same  as  that  of  Louis  IX,  St.  Louis  of  France,  1236-70.  He 
was  a  contemporary  of  two  great  Popes,  Gregory  IX  (1227-41) 
and  Innocent  IV  (1242-54),  and  of  the  Emperor  Frederic  II,  the 
new  'Stupor  Mundi ',  who  died  in  1250.  Two  great  Councils  were, 
held  in  his  time  at  Lyons,  and  two  Crusades  were  undertaken, 
while  the  Latin  Empire  of  (Jonstantinople  came  to  its  end  and 


122  lUKiKK    I5AC0N  AND  TICK  STATE  OF 

tlu*  ({reck  rule  tli<M<'  was  rosloicd.  The  Mongols  liad  spread  out 
and  conquered  from  Cliiiwi  to  Silesia.  KurojM?  iroiii  end  to  end 
was  fill(^d  with  unrest  and  eritieisni  of  esta])lislied  aiitliority,  while 
autliority  was  assorting  itself  with  varying  dcigrces  of  success. 
'J'he  strife  fx'tween  Po])e  and  EnijH'ror  (;nded  in  the  defeat  of  the 
llohenstauffen  and  the  extinction  of  his  line,  leaving  the  Imperial 
crown  vacant  for  a  score  of  years.  Heresy  stoutly  fought  a  losing 
l>attle  in  the  south  of  France,  wliile  in  tlie  north  free  cities  estab- 
lislied  their  rights  under  the  royal  ])rotection.  In  England  the 
controversies  begun  under  John  culminated  in  the  summoning  of 
a  Parliamentary  assembly  by  Simon  de  Montfort  in  1265  before 
his  defeat  and  death  at  Evesham.  Among  the  masses  this  feeling 
of  unrest  manifested  itself  in  opposition  to  the  clergy,  usually  by 
a  more  or  less  good-humoured  incredulity  towards  their  personal 
character  and  teaching,  but  sometimes  showing  itself,  as  in  the 
case  of  the  revolt  of  the  Pastoreaux,  in  the  determination  to 
destroy  the  clergy,  suppress  the  monks,  and  turn  on  the  knights 
and  lords,  as  the  Custos  of  the  Franciscans  of  Paris  puts  it. 

Civilized  Europe  was  in  those  days  comparatively  small. 
Roughly  speaking,  from  the  Black  Sea  to  the  North  Sea  the 
northern  boundary  of  civilization  lay  along  the  valleys  of  the 
Danube  and  the  Rhine,  and  its  common  language  was  some  sort 
of  French,  from  England  to  Constantinople,  and  along  the  Medi- 
terranean. French  nobles  ruled  in  Athens  and  Thebes,  a  French 
king  gained  the  crown  of  the  Sicilies,  and  everywhere  there  was 
a  movement  to  and  fro  which  made  for  internationalism.  With 
the  end  of  the  thirteenth  century  this  particular  unifying  influence 
had  decreased  almost  to  the  vanishing-point,  but  others  remained, 
only  less  potent.  Every  magnate  of  Europe,  lay  or  clerical,  had 
at  some  time  or  another  of  his  career  business  to  transact  with 
the  Papal  Court :  and  this  caused  a  continual  stream  of  suitors 
journeying  to  Rome  or  returning  from  it  to  their  own  lands. 
Every  prelate  had  to  visit,  at  least  once,  the  threshold  of  the 
'Apostle,  every  ecclesiastical  lawsuit  found  there  its  final  court  of 
appeal.  The  existence  of  the  great  Universities  was  another 
influence  making  for  the  international  spirit.  The  readiest  way 
to  high  promotion  in  the  Church,  and  often  in  the  State,  for 
a  poor  man,  was  eminence  in  the  law.  Canon  or  Civil,  and  this 
eminence  could  only  be  attained  in  the  schools  of  Bologna,  w^hile 
Theology,  the  Queen  of  Sciences,  had  her  chosen  seat  at  Paris, 


SCIENCE  IN  THE  THIRTEENTH  CENTURY         123 

and  welcomed  students  from  every  country  to  her  bosom.  Lastly, 
modern  commerce  was  beginning  to  appear  in  the  great  cities 
situated  on  the  routes  between  the  East  and  the  West ;  and 
Florence,  Genoa,  and  Venice  were  extending  their  relations  in 
every  direction  within  the  ring-fence  of  Christendom,  and  sending 
outposts  to  the  ends  of  tlie  known  earth.  Interpenetrating  all 
this  was  the  Jewish  communit}^,  whose  solidaritj^  and  love  of 
learning  make  the  exact  amount  of  its  influence  on  Christendom 
hard  to  estimate. 

The  temperament  of  this  great  commonwealth  is  reflected  in 
its  popular  literature,  especially  that  of  France.  The  two  great 
vernacular  works  of  Bacon's  period  are  Reynard  the  Fox  and  the 
first  part  of  the  Romance  of  the  Rose,  the  former  a  satiric  criticism 
of  life — of  Church  and  State,  not  political  but  human  ;  the  second, 
gathering  up  all  the  poetry  of  its  predecessors  and  veiling  it  in 
a  symbolism  instinct  with  study.  No  one  can  be  said  to  have 
any  real  conception  of  mediaeval  thought  to  whom  these  books 
do  not  appeal.  The  passionate  love  of  beauty  and  the  tolerance 
for  human  weaknesses  of  the  age  reveal  themselves  too  in  the 
architecture  and  the  sculpture  of  such  a  church  as  Rheims  was  as 
much  as  in  the  literature  of  the  day :  they  are  a  background 
which  must  be  borne  in  mind  while  our  attention  is  directed  to 
other  aspects  of  the  thought  of  the  day. 

As  the  distinguishing  feature  of  the  late  twelfth  century  was] 
a  revival  of  literature,  so  the  thirteenth  century  was  distinguished 
by  a  revival  of  science.  The  immediate  cause  of  this  was  the; 
introduction  of  the  scientific  works  of  Aristotle  to  western  Europe, 
in  nearly  every  case  through  the  medium  of  Arabic  translations. 
Up  to  the  middle  of  the  twelfth  century  the  only  works  of  Aristotle 
known  were  the  Categories  and  De  Interpretatione  in  the  translation 
of  Boethius,  which,  with  the  Isagoge  of  Porphyry  and  the  Timaeus 
of  Plato,  represented  to  Western  Europe  the  sum  total  of  the 
scientific  work  of  the  Greeks.  Not  that  Greek  was  unknown  in 
these  lands  ;  on  the  contrary,  a  knowledge  of  it  seems  to  have 
been  fairly  common,  but  the  interest  of  the  learned  of  the 
Byzantine  Empire  and  of  Magna  Grecia  lay  in  mysticism  and 
devotional  theology,  while  the  ordinary  speaker  of  Greek  was 
about  as  fitted  to  translate  Aristotle  as  an  English  merchant  in 
an  Asiatic  port  would  be  to  translate  modern  philosophy  or 
biology  into  the  language  of  his  surroundings. 


124  ROOER    BACOiN    AND  THIO  STATE  OF 

It  wius  ill  tlK'  Arabic-.spoaking  countrieH  that  the  new  seicntiftc 
inovcment  began.  Its  great  names  areAvicenna  (d.  1057),  Algazel 
(d.  1111),  and  Averroes  (d.  1  IDS).  Tlieir  eommentarie«  on  tiie 
text  of  Aristotle  represented  the  liighest  point  of  the  efforts  of 
the  battle  between  reason  and  faith,  between  the  ])}iilosophcrs 
and  the  theologians  of  Islam.  The  battle  s])read  from  Islam  to 
the  Synagogue,  but  though  the  Mohammedan  theologians  finally 
crushed  the  school  of  Araliie  Aristotelianism,  its  Jewish  disciples 
carried  on  the  tradition,  and  jilayed  a  not  uniinjiortant  part  in 
its  transfer  to  the  Christian  community. 

The  texts  used  by  the  Arabs  were  translations,  in  some  cases 
made  from  Syriac  versions,  in  others  directly  from  the  Greek  ; 
from  manuscripts  not  always  perfect,  as  may  be  seen  from  the 
phrase  '  album  in  Greco  ' — a  blank  space  in  the  Greek — so  often 
met  with  in  early  Latin  manuscripts  of  Aristotle.  When  these 
translations  were  turned  into  Latin,  it  was  usually  by  means  of 
two  persons,  a  Jew  or  native  who  knew  Arabic  and  gave  the 
sense  of  the  passage  in  Latin  or  the  vernacular,  and  a  writer  who 
set  down  the  passage  in  a  more  or  less  coherent  and  intelligent 
form.  A  good  deal  of  our  information  as  to  these  versions  comes 
from  the  pen  of  Bacon  himself,"  who  knew  personally  some  of  the 
translators,  and  was  markedly  sensible  of  the  faults  in  their  work- 

The  spread  of  knowledge  in  the  thirteenth  century  lay  through 
three  distinct  channels,  the  Universities,  the  schools  of  rehgious 
houses  both  of  the  older  orders  and  of  the  new  friars,  and  through 
Uttle  groups  and  individual  scholars  working  on  their  own  account 
without  any  organization  to  back  them  up.  The  Universities 
were  the  chief  means  of  spreading  the  study  of  philosophy  and 
theology  ;  the  religious  houses  more  or  less  preserved  the  chain 
of  literary  study  and  of  historiography,  in  addition  to  their  normal 
devotional  wTiting  ;  while  the  study  of  astronomy,  cosmogony, 
alchemy,  and  such  experimental  science  as  existed  was  in  the 
hands  of  small  groups  such  as  those  of  Pisa,  Marseilles,  and 
London,  w^ho  issued  astronomical  tables  for  the  calculation  of  the 
position  of  the  sun,  moon,  and  planets  ;  of  the  alchemists  of  Italy, 
France,  and,  perhaps,  England  ;  and  of  such  experimentors  as 
Peter  de  Maricourt,  the  '  magister  experimentorum ',  and  others 
whose  name  and  work  are  lost  to  us  by  their  isolation  and  obscurity. 
Bacon  himself  for  many  years  of  his  life  seems  to  have  belonged 
to  this  class. 


SCIENCE  IN   THE   THJRTEENTH   CENTURY        125 

It  is,  however,  to  the  Universities  that  we  must  turn  for  tlie 
main  influences  on  European  thought,  and  more  es])ecially  to 
Paris  and  Oxford.  It  was  to  them  that  the  new  Aristotehanism 
came,  at  first  possibly  as  summaries  of  the  text  with  the  com- 
mentaries of  Avicenna  and  Algazel,  and,  as  curiosity  was  aroused, 
by  more  or  less  complete  versions  of  the  text  of  '  The  Philosopher  ' 
himself  (Aristotle)  and  of  the  works  of  '  The  Commentator ' 
(Averroes).  The  first  of  these  versions  that  we  can  date  with 
certainty  were  made  in  Spain  about  1150  at  Toledo,  which  long 
continued  to  be  a  centre  of  translation.  It  was  from  there  that 
the  new  text-books  came,  according  to  Giraldus  Cambrensis,  '  libri 
quidam  tanquam  Aristotelis  intitulati  Toletani  Hispanic  finibus 
nuper  inventi  et  translati,  Logices  quodam  modo  doctrinam  pro- 
fitentes  ',  which  led  to  the  adoption  of  so  many  '  novitates  et 
liereses  '  that  their  use  was  prohibited  in  Paris  in  1210.  These 
must  have  caused  inquiry  at  Constantinople  after  its  capture  by 
the  Latins  in  1204,  for  in  1209  we  learn  '  legebantur  Parisiis  libelli 
quidam  de  Aristotele  ut  dicebantur  compositi,  qui  docebant  Meta- 
physicam,  delati  de  novo  a  Constantinopoli  et  a  Greco  in  Latinum 
translati,  qui  .  .  .  iussi  sunt  omnes  comburi  ',  at  the  council  next 
year. 

Thus  reaction  triumphed  for  a  while,  and  in  the  earliest  statutes 
of  the  University  of  Paris  (1215)  dealing  with  the  course  of  study 
we  find  that  the  only  works  of  Aristotle  studied  were  the  old  and 
new  Dialectics  and  the  Nichomachea7i  Ethics  (four  books)  with  the 
Topics  of  Boethius.  The  prohibition  was  renewed  by  Gregory  IX 
in  1231,  but,  long  before,  the  Physics  in  one  form  or  another  were 
studied.  Giraldus  Cambrensis,  in  his  old  age  (c.  1220),  complains 
of  young  men  arriving  at  the  professorial  chair  (the  M.A.  degree) 
in  three  or  four  years  instead  of  the  twenty  years  of  his  own  time, 
and  devoting  themselves  to  logic  and  physics  instead  of  the  poets 
and  historians  who  used  to  be  studied.  WilHam  of  Auvergne, 
who  became  Bishop  of  Paris  in  1228  and  was  still  writing  in  1248, 
quotes  the  Metaphysics,  the  De  Anima,  the  Physics,  the  De  Caelo 
et  Mundo,  the  Meteorics,  the  De  Aimnalibus,  the  De  Somno  et 
Vigiliis,  and  the  Ethics.  Everything  goes  to  prove  that  the  end 
of  the  first  quarter  of  the  thirteenth  century  saw  a  nearly  complete 
Aristotle  in  the  hands  of  the  Western  world.  But  in  jjractice 
these  translations,  passing  through  the  hands  of  unnumbered  and 
anxious  copyists,  soon  grew  to  be  wofully  corrupt.     Even  Bacon 


12()  lUKiF.It    liACOX   AND  THh]   STATK  OF 

liiinscir,  Icctiirin;^  at  I'aris,  is  led  into  accK.'ptiii^  as  a  dictum  of 
Aristotle  tiie  exact  opposite  of  what  now  appears  in  the  mediaeval 
texts,  and  we  may  |)er!iaps  attribute  to  this  unfortunate  experience 
a  })art  of  tlie  criticisms  wiiicli  lie  lavishes  on  tlic  ignorance  of  the 
li'uiislators. 

It  was  not,  however,  the  study  of  Aristotle  that  first  aroused 
the  mind  of  western  Europe  to  the  pursuit  of  science.  Only  one 
branch  of  study  at  that  ])eriod  could  present  in  the  fullest  way 
the  essential  requisites  for  a  complete  science,  the  study  of  Astro- 
nomy. Its  two  branches,  theoretical  and  experimental,  allowed 
for  close  and  detailed  observation,  the  construction  of  theories 
founded  on  that  observation,  the  prediction  of  future  phenomena 
from  theory,  and  the  verification  of  these  i)redictions,  in  a  way 
that  no  other  studj'^  could  begin  to  approach  :  the  only  other 
scientific  studies  of  that  time,  Medicine  and  Alchemy,  being  at 
the  stage  of  empirical  arts.  Astronomy  was  another  of  the 
heritages  of  Europe  from  the  Arabs.  Since  the  time  of  the  Greeks 
its  greatest  advances  had  been  made  in  the  country  of  its  origin, 
at  Bagdad.  The  Almagest  of  Ptolemy  was  translated  into  Arabic 
about  A.  D.  800  and  reached  Europe  at  the  end  of  the  twelfth 
century.  The  observatory  at  Bagdad  w^as  a  centre  of  study,  and 
here  Thebit  w^as  led  to  his  theory  of  the  trepidation  of  the 
equinoxes  to  explain  discrepancies  between  the  calculated  and 
observed  positions  of  the  heavenly  bodies.  From  here  a  constant 
influence  was  exercised  west  and  east  from  Granada  and  Cairo  to 
Samarkand.  With  better  observations,  more  correct  tables  were 
from  time  to  time  calculated  and  issued,  and  these  tables  were 
seized  on  by  the  Western  world  when  they  came  into  their  hands, 
and  adapted  to  their  use.  With  each  advance  in  precision  came 
improvements  in  geometrical  methods,  more  accuracy  in  the 
determination  of  periods  Uke  the  length  of  the  solar  year  or  the 
relation  of  its  length  to  the  lunar  month,  to  name  no  others. 
But  in  all  this  Arab  science  there  was  no  fundamental  difference 
from  its  Greek  source,  nothing  was  changed  by  the  additions 
made,  so  that  when  it  came  into  Europe  it  harmonized  well  with 
the  traditional  astronomy  handed  down  from  the  Latins  by  Isidore 
of  Seville  and  his  copyists. 

The  science  of  Mathematics  had  grown  with  the  needs  of 
Astronomy  :  the  art  of  the  algorists  had  been  improved  by  the 
pubUcation  of  the  Liber  Abaci  of  Fibonacci  in  1202,  and  was  now 


SCIENCE  IN  THE  THIRTEENTH  CENTURY        127 

perfectly  adequate  not  only  for  the  ordinary  needs  of  commerce 
but  for  the  intricate  calculations  demanded  by  the  observatii^ns 
of  astronomers  :  a  general  method  of  extracting  roots  had  been 
obtained,  and  was  taught  in  the  ordinary  Mork  of  the  schools. 
The  works  of  Euclid  had  been  translated  by  Adelard  of  Bath  in 
the  twelfth  century  and  were  revised  by  Campanus  of  Novara 
in  1246,  and  a  sufficient  amount  of  spherical  geometry  had  been 
obtained  for  the  needs  of  the  day,  while  a  sort  of  algebra  and  the 
elements  of  trigonometry  only  awaited  a  scientific  nomenclature 
to  be  recognized  as  new  branches  of  the  science.  What  was 
needed  to  make  it  a  vigorous  study  were  better  teachers  and 
a  wider  outlook. 

The  science  of  medicine  received  a  new  impulse  in  the  earlj- 
part  of  the  thirteenth  century  by  the  translation  of  the  medical 
work  of  Avicenna,  made  by  the  order  of  Frederick  II — a  transla- 
tion which  dominated  the  teaching  of  medicine  till  the  seventeenth 
century,  and  long  survived  its  usefulness.  It  furnished  a  complete 
body  of  medical  teaching,  theoretical  and  practical,  and,  though 
Avicenna  did  not  differ  greatly  from  his  Eastern  predecessors,  it 
introduced  some  new  theoretical  principles  as  a  foundation  or  as 
an  explanation  of  medical  practice.  But  this  translation  was 
only  one  of  the  services  rendered  to  medical  science  by  the  court 
of  Sicily :  a  far  greater  one  was  the  insistence  on  the  value  of 
dissection  in  the  course  of  medical  study.  In  1231  the  Emperor 
issued  an  ordinance  forbidding  any  one  to  practise  surgery,  unless 
he  had  studied  at  least  a  year  in  human  anatomy,  and  he  is  said 
(on,  we  are  afraid,  insufficient  grounds)  to  have  ordered  the  medical 
schools  of  Salerno  to  dissect  publicly  a  human  corpse  at  least 
once  in  five  years.  But  it  cannot  be  said  that  this  practical  side 
of  the  study  of  medicine  has  left  much  trace  on  the  ^mtings  of 
the  thirteenth  century,  perhaps  because  surgeons  were  of  an  inferior 
class  to  physicians,  regarded  as  handicraftsmen  simply  obeying  their 
orders,  perhaps  because  the  needful  stimulus  to  original  thought 
was  drowned  by  the  vast  mass  of  literature  thrust  upon  it. 

Later  in  the  century  the  University  of  Bologna  was  a  great 
centre  of  medical  teaching.  An  English  bishop  of  Durham  in 
1241,  Nicholas  of  Farnham,  had  been  a  professor  of  medicine  in 
Bologna,  but  the  formation  of  a  scientific  school  there  dates  from 
about  1260  and  is  associated  with  the  name  of  Thaddeus  of 
Florence,  who  seems  to  have  founded  his  teaching  on  x\vicenna. 


12S  |{()(JI^:il    I^ACON    AND   THK   STATK   OK 

It  is  to  R()lnn;n;t  |;it«  r  on  at  tlic  nid  of  the  (('iitiiry  lliat  \v(^  owe 
the  flosc  comicxioM  hctwccii  medicine  and  astrolof^y.  Surgery 
was  well  taught  there,  judging  hy  tlu;  many  famous  names  of  its 
|)U|)ils — Tlieodorie  of  Lueea,  VVilham  of  Sahceto,  and  Kohind  of 
Parma  among  otiiers.  Anatomy  was  tauglit  by  pubhc  animal 
dissections  to  which  medical  students  of  ov(;r  two  years'  standing 
were  admittcnl. 

Of  the  Ex peii mental  Science;  of  th(5  early  thirteenth  century 
we  kiiow  almost  nothing  (5xce])t  that  it  existed,  and  that  some 
teachers  of  it  were  famous  (enough  to  be  called  '  Ex[)erimejitator  '. 
Thomas  of  (.^antimpre  quotes  one  such.  Villars  d'Honcourt,  the 
thirteenth-century  architect,  has  left  us  a  sketch  of  a  per})etual 
motion  machine  he  had  designed,  the  properties  of  the  magnet 
had  been  studied,  and  it  is  difificult  to  believe  that  the  fine  archi- 
tecture of  the  period  was  arrived  at  without  an  exact  knowledge 
of  mechanical  law. 

Chemistry  and  Alchemy  were  indistinguishable,  but  metallurgy 
was  sufficiently  advanced  to  ensure  that  the  properties  of  the 
commoner  metals  and  ores  were  known  experimentally  and  that 
a  theory  to  account  for  their  more  obvious  properties  should  be 
evolved.  One  has  only  to  consider  the  number  of  treatises  quoted 
by  Albertus  Magnus  to  realize  the  mental  activity  expended  on 
this  subject.  But  no  scientific  study  was  possible  until  a  much 
wider  and  deeper  knowledge  was  attained,  sufficient  to  indicate 
the  points  to  which  inquiry  should  be  devoted.  In  the  thirteenth 
century  only  empirical  knowledge  could  be  hoped  for. 
I  In  this  world  of  awakening  science  Roger  Bacon  began  to  take 
I  part  somewhere  about  1235,  after  having  been  at  Oxford  for 
some  years,  and  having  possibly  attended  the  teaching  of  Grosse- 
teste,  who  w^as  lecturing  in  the  Franciscan  schools  from  about 
1230  to  1235.  There  is  no  doubt  that  Grosseteste  {maximus 
naturalis  et  perspectivus  quern  vidi)  was  the  man  from  whom  more 
than  any  other  Bacon  derived,  not  only  much  of  his  knowledge 
„iand  many  of  his  theories,  but  above  all  his  love  of  mathematics 
i/'and  his  insistence  on  the  value  of  a  mathematical  demonstration. 
But  certain  features  of  his  early  teaching  of  astronomy  in  the 
notes  of  his  lectures  preserved  by  the  Amiens  manuscript  lead  us 
to  the  conclusion  that  Bacon's  early  studies  were  in  the  hands  of 
more  conservative  teachers,  whose  astronomy  was  derived  from 
that  current  before  the  invasion  of  Mohammedan  science. 


SCIENCE  IN  THE  THIRTEENTH  CENTURY        129 

However  that  may  be,  Bacon  seems  to  have  come  to  Paris  with 
a  reputation  good  enough  for  him  to  be  taken  u])  by  the  Chancellor 
of  the  University,  who  advised  him  in  the  direction  of  further 
studies.  Bacon  was  recommended  to  study  medicine,  and  to 
apply  himself  to  the  composition  of  a  work  on  some  branch  of  it. 
The  subject  he  selected  was  the  relief  of  old  age,  and  his  Epistola 
de  accidentihiis  senectutis,  dedicated  and  sent  to  Innocent  IV 
(1243-54),  was  the  result.  In  the  preparation  of  this  work  Bacon 
visited  Italy  '  in  partibus  Romanis  '  and  made  himself  acquainted 
with  those  works  of  Mohammedan  medicine  which  had  been 
introduced  into  Europe.  His  book  is  largely  a  compilation, 
perhaps  one  of  the  most  complete  on  its  subject  that  has  been 
made,  from  Avicenna,  Rhazes,  Haly,  Isaac,  and  Damascenus,  and 
contains  little  that  would  mark  out  its  wTiter  as  an  independent 
or  innovating  spirit.  It  was  after  this  visit  that  Bacon  began  the 
study  of  Greek,  then  a  spoken  and  written  language  in  southern 
Italy,  as  his  treatise  makes  it  pretty  evident  that  he  knew  no 
Greek,  Hebrew,  or  Arabic  at  the  time,  his  knowledge  of  Greek 
medicine — Galen  and  Dioscorides — being  obtained  from  Italy. 

We  owe  to  the  piety  or  the  industry,  it  would  seem,  of  one 
of  the  pupils  of  Roger  Bacon  a  report  of  several  of  the  courses 
given  by  him  as  a  regent  master  at  Paris.  They  consist  of  two 
courses  on  the  Physics  of  Aristotle  and  three  on  the  Metaphysics, 
with  another  on  the  De  plantis.  An  examination  of  the  contents 
assures  us  that  we  have  in  the  questions  on  the  Physics  the  report 
of  two  distinct  courses,  not  two  reports  of  the  same  lectures,  and 
the  three  sets  of  questions  on  the  Metaphysics  must  belong  to  at 
least  two  courses  and  most  probably  three.  As  the  Physics  and 
Metaphysics  were  lectured  on  at  the  same  time  in  1245,  and  most 
likely  earlier,  we  thus  have  records  of  three  years'  teaching — 
ending  most  probably  in  or  before  1247.  We  put  this  date  because 
Bacon,  writing  in  1267  or  1268,  speaks  of  the  twenty  years  in 
which  he  had  laboured  specially  in  the  study  of  wisdom,  after 
abandoning  the  usual  methods. 

These  lectures  bear  the  mark  of  youth — a  youth  of  genius. 
They  have  been  examined  at  some  length  by  the  late  M.  Duhem, 
who  has  made  it  plain  that  the  principal  subjects  dealt  with  in 
them  are  those  which  preoccupied  Bacon  throughout  his  career, 
and  that  his  treatment  shows  a  progressive  growth  in  knowledge 
and  boldness  of  views.     Even  at  this  early  stage  of  his  career  he 


\'M)  iu)(;ek  bacon  and  thi^:  statk  of 

i.s  an  innovator,  and  it  is  to  IiIh  oxpo.sition  of  the  question  as  to 
(]w  ('xist(MH!(^  of  a  vacinini,  that  meciiaeval  Hcience  owed  the 
theory  wliicli  lieid  sway  for  centuries  till  new  facts  were  observed 
wliich  showed  its  nnsoiiiidness,  a  tlieory  crystallized  into  the 
expression  '  Nature  abhors  a  vacuum  '.  ft  is  pi'(^bable  that  the 
earlier  course  re])resents  the  views  current  at  Oxford,  the  later 
was  certainfy  given  at  Paris. 

The  style  of  these  early  works  has  little  in  common  with  that 
of  twenty  years  later,  and  this  offers  a  warning  to  us,  forbidding 
the  rejection  of  works  attributed  to  Bacon  merely  on  account  of 
their  style,  provided  that  their  subjects  and  treatment  permit  of 
their  being  placed  among  the  '  multa  in  alio  statu  .  .  .  propter 
iuvenum  rudimcnta  '  written  by  him,  or  the  '  aliqua  capitula 
nunc  de  una  scientia  nunc  de  alia  .  .  .  aliquando  more  transitorio  '. 
There  is,  it  is  true,  none  of  the  fierce  and  outspoken  criticism 
which  marks  his  later  work,  but  it  must  be  remembered  that  few 
■  of  the  abuses  he  attacks  had  come  into  existence.  His  period  of 
lecturing  must  have  coincided  with  the  last  teaching  of  Alexander 
of  Hales,  who  died  in  1245,  and  the  first  appearance  of  Albertus 
Magnus  in  the  Jacobin  convent  at  Paris  in  the  same  year,  and 
he  had  retired  from  his  chair  before  St.  Thomas  came  to  lecture 
1  at  Paris  in  1252.  His  teaching  compares  favourably  with  that 
'  of  Albert,  as  preserved  in  the  Commentary  on  Aristotle's  Physics, 
^vritten  most  probably  at  or  soon  after  this  period. 

It  is  in  astronomy  that  these  lectures  show  best  the  fluid 
state  of  Bacon's  knowledge.  In  the  earlier  of  them,  that  on  the 
eleventh  Metaphysics,  his  theory  is  a  development  of  the  Aristo- 
telian reasoning  in  the  de  Caelo  et  Mundo.  He  seems  entirely 
ignorant  of  the  Ptolemaic  theories,  and  to  found  his  teaching 
on  the  Commentator  of  the  Timaeus  rather  than  on  Alpetragius. 
His  theories  are  those  of  the  twelfth-century  school  of  Chartres. 
In  his  second  lectures  on  the  Physics  his  knowledge  of  contem- 
porary astronomical  theory  is  greatly  enlarged.  He  now  finds  the 
necessity  of  supposing  nine  orbs  instead  of  eight,  to  account  for 
the  precession  of  the  equinoxes,  and  though  he  is  not  yet  prepared 
to  acknowledge  the  opposition  between  the  homocentric  system 
of  Aristotle  and  that  of  the  school  of  Ptolemy,  he  is  e\ndently  on 
the  road  to  this  position. 

We  cannot  with  any  certainty  give  a  reason  for  Bacon's  with- 
drawal from  his  work  as  a  master  at  Paris.     It  may  have  been 


SCIENCE  IN  THE  THIRTEENTH  CENTURY        131 

due  to  the  public  affront  he  received,  when,  bunghng  over  a  strange 
word  in  the  text  of  the  De  plantis  he  was  explaining,  and  calling 
it  Arabic,  one  of  his  students  replied  that  it  was  Spanish.  Certainly 
it  is  a  curious  fact  that  the  reported  lectures  on  this  book  break 
off  just  before  the  point  at  which  this  passage  occurs.  At  any 
rate  we  may  date  from  this  period  his  resolution  to  become 
a  master  of  the  languages  in  which  the  fundamental  documents 
of  religion  and  science  were  written. 

It  was  about  this  time  that  a  revival  of  the  teaching  of 
mathematics  in  the  University  of  Paris  took  place,  following  the 
republication  of  the  Euclidean  corpus  by  Campanus  of  Novara  in 
1246.  Bacon  tells  us  that  he  attended  the  lectures  of  many  new 
masters  on  mathematics,  but  found  that  they  did  not  understand 
the  terminology  of  their  subjects,  so  that  he  supplied  them  with 
geometrical  proofs  of  positions  from  Aristotle  and  Averroes  which 
none  of  the  official  critics  in  the  disputations  could  attack.  About 
this  time  (1248),  Bacon  seems  to  have  learnt  from  Grosseteste  his 
theory  as  to  the  origin  of  the  tides  and  now  probably  began 
that  intensive  study  of  natural  science  of  which  his  work  bears 
such  witness.  He  writes  in  1267  that  during  the  last  twenty  years 
he  had  spent  more  than  2,000  livres  (a  sum  equal  in  purchasing 
power  to  something  under  £10,000  at  present)  in  purchasing  secret 
books,  on  various  experiments,  languages,  and  instruments,  and 
astronomical  tables,  in  forming  friendships  with  the  wise,  and  in 
instructing  helpers  in  languages,  figures,  numbers,  tables,  instru- 
ments, and  the  like. 

The  experiments  to  which  he  devoted  his  attention  may  be 
gathered  from  his  account  of  the  mysterious  Peter  de  Maricourt, 
whom  he  seems  to  have  met  about  this  time.  The  account  of 
him  in  the  Opus  Tertium  seems  to  be  Bacon's  ideal  of  a  student. 
'  He  makes  no  account  of  speeches  and  wordy  conflicts  but  follows 
up  the  works  of  wisdom  and  remains  there.  He  knows  natural 
science  by  experiment,  and  medicaments  and  alchemy  and  all 
things  in  the  heavens  or  beneath  them,  and  he  would  be  ashamed 
if  any  layman,  or  old  woman  or  rustic,  or  soldier  should  know 
anything  about  the  soil  that  he  was  ignorant  of.  Whence  he  is 
conversant  with  the  casting  of  metals  and  the  working  of  gold, 
silver,  and  other  metals  and  all  minerals  ;  he  knows  all  about 
soldiering  and  arms  and  hunting  ;  he  has  examined  agriculture 
and  land  surveying  and  farming  ;    he  has  further  considered  old 


i:!l>  iukikii  I5A(X)N  and  tkk  statk  or 

wives'  muLiic  iiiid  lort  iinc-tclliii^  and  {\\v  clianiis  ol  tlicm  and  ol 
all  inaj^icians,  and  llic  tricks  and  illusions  of  jugglers.  But  as 
honour  and  tcuards  would  hinder  him  from  the  greatness  of  his 
experimental  woik  he  scorns  them.'  We  learn  that  in  1267  he  had 
just  completed  a  concave  minor  capable  of  actinjjj  as  a  buining- 
glass,  after  three  years'  work,  at  an  expense  of  100  hvr(\s. 

A  reflection  of  this  acquaintance  may  he  found  in  the  rather 
puzzling  work  known  under  the  name  of  Dc  mirahili  potestalt 
arh'.s  (it  naturae,  consisting  of  ten  or  eU^vcji  chapters,  of  which  the 
jfirst  six  nuist  have  been  written  about  this  tinie,  prompted,  there 
is  little  doubt,  by  a  recent  denunciation  by  William  of  Auvergne, 
Bishop  of  Paris,  of  dealings  in  magic.  The  remaining  chapters 
are  of  a  different  character  and  may  possibly  have  formed  part 
originally  of  another  work. 

The  principal  subject  of  these  chapters  is  a  delimitation  of  the 
wonders  that  can  be  wrought  by  an  application  of  scientific 
principles  from  those  which  are  mere  trickery  or  those  which  may 
be  due  to  the  powers  of  evil.  He  seems  to  have  gone  thoroughly 
into  the  question  of  magic,  and  to  have  attended  the  thirteenth- 
century  s])iritualistic  seances.  '  When  inanimate  objects  are 
quickly  moved  about  in  the  darkness  of  morning  or  evening 
twilight,  there  is  no  truth  therein  but  downright  cheating  and 
cozenage.'  He  allows  a  certain  utility  in  charms,  for  example  in 
the  hands  of  a  physician,  that  the  patient  may  be  induced  to 
hope  and  confidence  of  a  cure,  quoting  Avicenna  as  to  the  effect 
of  the  mind  on  the  body.  He  then  proceeds  to  give  a  general 
explanation  of  the  waj^  in  which  one  person  or  thing  can  act  on 
another,  confusing  what  we  now  recognize  as  infection,  sympathy, 
and  hy])notism  into  one  class  of  action  at  a  distance,  and  while 
repudiating  such  books  as  pay  worship  to  evil,  warns  his  reader 
that  many  books  reputed  magical  contain  much  useful  knowledge. 

He  then  proceeds  to  describe  a  few  of  these  wonders,  which  give 
us  some  idea  of  what  were  really  the  mechanical  problems  of  the 
time.  The  first  is  a  ship,  without  men  rowing  yet  moving  faster 
on  rivers  or  the  sea  than  a  galley.  This  seems  to  point  either  to 
an  improved  form  of  sails,  or  to  something  like  a  paddle  moved 
with  cranks.  The  car  moving  without  animals  to  draw  it  may 
have  depended  on  the  same  thing,  the  real  obstacle  to  its  use 
being  the  want  of  good  roads.  The  flying  machine  with  wings 
he  acknowledges  has  only  existed  in  plans.    The  small  instrument 


SCIENCE    IN  THE  THIRTEENTH  CENTURY        133 

for  lifting  weights  is  evidently  a  sort  of  jack,  unless  it  is  a  system 
of  pulleys  ;  similarly,  the  instrument  by  which  one  man  can  pull 
a  thousand  toward  him.  Walking  under  the  sea,  building  suspen- 
sion bridges,  and  so  on,  are  also  mentioned  by  him  as  possible  at 
the  time.  He  himself  lays  much  stress  on  the  properties  of  mirrors. 
Some  of  these  appear  obvious  enough  to  us,  such  as  the  arrange- 
ment by  which  images  of  an  object  are  repeated  indefinitely, 
which  it  is  difficult  to  believe  had  not  been  observed  before, 
though  he  uses  it  to  explain  the  existence  of  parhelia  and  mirages, 
and  proposes  its  utilization  in  war.  He  also  speaks  of  an  arrange- 
ment of  lenses  by  which  distant  things  may  be  brought  near  and 
small  things  made  visible:  '  possunt  enim  sic  figurari  perspicue 
ut  longissime  appareant  propinquissima,  et  e  converse.'  This  is 
undoubtedly  a  description  of  the  telescope  without  the  enclosing 
tube.  Such  an  arrangement  is  known  to  have  been  made  by 
Leonard  Digges,  who  died  in  1571,  from  his  study  of  Bacon's 
works.  The  magic-lantern  is  not  obscurely  hinted  at,  in  a  descrip- 
tion of  some  optical  illusions.  But  Bacon  reserves  his  greatest 
praise  for  the  use  of  lenses  and  mirrors  as  burning-glasses,  and 
for  the  construction  of  a  self-moving  celestial  globe,  probably 
dependent  on  the  use  of  a  magnet,  as  was  that  of  Peter  de  Mari- 
court.  He  further  describes  some  inflammable  mixtures  and  an 
explosive  mixture  which  later  on  proves  to  be  gunpowder. 

We  do  not  know  how  much  of  this  period  of  investigation  was 
spent  at  Paris,  and  everything  points  to  the  fact  that  Bacon  re- 
turned to  Oxford  about  1251  and  entered  the  Franciscan  Order 
about  1253  to  1256.  But  during  these  years  of  absence  from  the 
University  schools  another  and  a  rival  influence  was  establishing 
itself  there. 

Albert  the  Great,  the  first  doctor  of  the  Dominican  Order, 
had  come  to  Paris  in  1245  ;  he  was  some  years  older  than  Bacon 
and  brought  with  him  a  great  renown  as  a  teacher.  He  was 
accompanied  by  his  pupil  and  socius  Thomas  Aquinas,  now  in  his 
eighteenth  year,  whose  fame  was  destined  to  put  his  own  in  the 
shade.  Their  task  was  to  explain  Aristotle  and  to  reconcile  him 
with  dogma.  In  some  respects  this  was  difficult.  Aristotle  tells  of 
no  Creator,  no  Adam,  no  Providence,  no  eternity  of  the  individual 
soul  after  death  ;  and  his  commentators  had  to  pass  over  these 
defects  in  silence,  sometimes  to  deny  the  plain  meaning  of  what  he 
wrote,  and  occasionally  to  throw  his  teaching  overboard  altogether. 

2391  2 


134  H()(JKR    BACON    AND    TIIK  STATK   OF 

Albert's  oncyclopaodic  work  on  tlic  P/if/.sirs  and  McUijihyHivH 
of  Aristotlo,  bogun  |)orha])H  before  1245  in  \  icw  of  liis  coming  to 
Varis,  was  ('oncludcd  })y  a})out  1250.  His  Jj()(jl('  and  his  Siirnnia 
are  parts  of  another  scheme.  It  was  written  as  a  resnlt  of  a  demand 
from  the  Dominicans  for  a  eompeiuhous  account  of  physics  which 
would  enabU^  tliem  to  understand  the  works  of  Aristotle  on  the 
su))je('t.  All)ert  felt  himself  unequal  to  the  task,  })ut  after  repeated 
entreaties  set  to  work  to  write  a  (Commentary  for  the  use  of  the 
friars  and  of  all  those  who  desired  to  attain  to  natural  science — 
a  commentary  many  times  longer  than  the  original  text.  He 
goes  on  to  describe  the  plan  on  which  he  worked,  and  to  explain 
that  there  are  three  divisions  of  real  ])hilosophy;  that  is,  philo- 
sophy not  caused  in  ourselves  by  our  own  work  like  Moral 
]*hilosophy.  These  three  parts  are  Natural  Philosophy  or  Physics, 
Metaphysics,  and  Mathematics  ;  and  he  ])romises  to  deal  with 
(nich  in  turn.  As  a  matter  of  fact  he  never  did  deal  with  Mathe- 
matics, and  it  is  probable  that  he  was  not  in  a  position  to  do  so, 
but  he  dealt  fully  with  everything  included  in  the  thirteenth 
century  in  Physics  and  Metaphysics. 

Albert  was,  beyond  doubt,  one  of  the  most  learned  men  of  his 
age,  as  Bacon,  his  severest  critic,  admits.  Writing  to  the  Pope 
in  1267  he  mentions  Albert  and  William  de  Shyrwood  as  the  two 
most  famous  scholars  of  the  day,  and  challenges  comparison  \vith 
them.  In  the  Opus  Minus  he  says  of  Albert,  '  truly  I  praise  him 
more  than  all  the  crowd  of  students,  for  he  is  very  given  to  study 
and  has  seen  an  infinite  number  of  things,  and  has  spent  much, 
and  so  has  been  able  to  collect  many  useful  facts  from  an  ocean 
of  authors '.  But  Bacon  insists  that  being  a  self-taught  student 
he  is  not  thoroughly  grounded,  seeing  he  was  never  trained  by 
hearing,  lecturing,  and  disputing  in  the  ordinary  arts  course. 
Moreover,  he  does  not  know  languages,  and  so  cannot  check  the 
errors  of  his  texts,  and  as  he  is  ignorant  of  the  laws  of  j)erspective 
he  cannot  fully  explain  any  part  of  natural  philosoi3hy. 

The  dates  of  Albert's  treatises  are  not  well  established,  and 
the  order  in  which  they  were  written  is  only  partty  known,  so 
that  we  cannot  say  how  far  Bacon's  statement  as  to  his  ignorance 
of  Greek  and  Arabic  was  true  at  the  time.  There  seems  no  doubt 
that  Albert  consulted  Greek  texts  and  j)robably  Arabic  ones, 
though  he  may  have  had  expert  help.  He  certainly  was  a  very 
keen  and  diligent  observer  ;    his  tracts   on  mineralogy  contain 


SCIENCE  IN  THE  THIRTEENTH   (CENTURY        135 

many  proofs  of  it.  Perhaps  this  was  because  he  could  not  find 
the  complete  book  of  Aristotle  de  Mlneralihus  :  '  que  diligenter 
quesivi  per  diversas  mundi  regiones  .  .  .  exul  enim  aliquando 
factus  fui  longe  vadens  ad  loca  metallica  ut  experiri  possem 
naturas  metallorum.'  He  goes  on  to  describe  his  investigations 
among  the  alchemists,  theoretical  and  practical,  and  compares  his 
impressions  with  his  own  knowledge  of  how  gold,  silver,  and 
other  metals  are  found  native  or  as  ores.  Of  course  these  studies 
may  have  followed  Bacon's  criticisms  and  resulted  from  them. 
We  know  that  Albert  was  sensitive  to  them. 

But  Bacon's  criticism  of  Albertus,  however  strong,  was,  from 
the  point  of  view  that  we  share  with  him,  well  founded.  The 
ideal  science  of  Albertus  Magnus  was  a  science  based  on  words  and 
books,  not  on  the  phenomena  of  nature.  He  looked  to  logic  for 
advance  in  knowledge.  '  Et  hoc  est  quod  per  investigationem 
rationis  ex  cognito  devenitur  ad  cognitionem  incogniti,  hoc  enim 
fit  in  omnia  scientia  quocunque  modo  dicta,  sive  sit  demon- 
strativa ',  he  says  in  asserting  the  claims  of  logic  to  be  a  science. 
'  Investigatio  enim  sive  ratio  investigans  ignotum  per  notum, 
speciale  quoddam  est.'  It  is  true  that  he  says  elsewhere,  '  Dicen- 
dum  quod  scientie  demonstrative  non  omnes  facte  sunt,  sed  plures 
restant  adhuc  inveniende  ',  but  these  demonstrative  sciences  are 
further  branches  of  logic,  not  sciences  founded  on  observation  of 
nature.  Similarly  the  statement,  '  Oportet  experimentum  non  in 
uno  modo  sed  secundum  omnes  circumstancias  probare  ',  does  not 
apply  to  experiments  in  natural  science  but  to  words.  Summing 
up  our  impressions,  his  influence  on  his  time  is  on  the  whole  bad ; 
his  value  for  us  is  that  he  presents  us  with  a  resume,  from  the 
scholastic  point  of  view,  of  the  knowledge  already  acquired  by 
western  Europe  at  the  end  of  the  first  half  of  the  thirteenth 
century. 

Albert's  great  pupil,  St.  Thomas,  enters  late  into  the  scheme  of 
Bacon's  surroundings.  He  may  have  been  the  '  Doctor  Parisius  ' 
on  whom  an  attack  is  made,  but  his  treatment  of  the  Aristotelian 
system  of  nature  seems  to  have  been  a  little  later  'u\  date  than 
the  Opus  Tertimn,  and  certainly  to  have  avoided  some  of  Bacon'a 
criticisms  by  an  attempt  to  obtain  a  new  version  made  directly 
from  the  Greek.  That  this  version  was  defective,  too,  was  not 
his  fault.  Thomas  was  lecturing  in  Paris  in  1252,  after  having 
spent  three  years  there  as  a  pupil  of  Albertus  in  124:5-8,  and  he 


136  RO(iI^]I<    IU(JON  AND  THE  STATK  OF 

took  Ills  (li\iiiily  dcjiiicc  at  tlic  Hame  time  as  Bonaventura  in 
1257.  His  coiniiiciitarie.s  on  tlie  Naluralia  of  Aristotle  are  said 
to  have  J)een  begun  in  1203,  and  lie  leetnred  in  Paris  again  from 
1268  to  1272,  wiien  he  left  to  take  uj)  a  post  in  the  reorganized 
llniversity  of  Nai)les.  The  '  duo  moderni  gloriosi  '  of  the  Com- 
munia  Naluralium  must  have  been  Albert  and  Thomas,  but  it  is 
not  till  later  that  Thomas  is  mentioned  (1271)  in  the  Compendium 
Stiidii,  with  Albert  as  an  example  of  tiie  '  pueri  duorum  ordinum 
studentium  ',  and  it  must  be  about  this  time  or  a  little  earlier 
(1268-9)  that  the  strictures  in  the  later  part  of  the  Communia 
Naturalium  on  his  doctrines  were  written.  '  Tem|)oribus  autem 
meis  non  fiebat  mencio  de  istis  erroribus.'  But  while  these  dis- 
cussions have  lost  much  of  their  meaning  to  us  of  this  day,  Thomas 
remains  the  greatest  of  the  schoolmen,  and  his  supremely  intel- 
lectual attitude  has  carried  over  his  theological  work  to  our  ow^n 
days  almost  unaltered. 

The  work  of  Albert  was  not  the  only  attempt  to  sum  up  the 
totality  of  human  knowledge  at  the  time.  Several  veritable 
encyclopaedias  were  composed  about  1250,  large  and  small, 
including  all  that  w^as  known  or  believed  about  the  universe. 
Of  these  the  most  notable  was  that  of  Vincent  of  Beauvais, 
a  Dominican  like  Albert  and  St.  Thomas,  who  wrote  between 
1240  and  1264  his  colossal  Imago  Mundi  divided  into  three 
sections — the  Speciilmn  Naturale,  Speculum  Doctrinale,  and  Specu- 
lum Historiale,  to  which  was  later  added  by  other  hands  the 
Speculum  Morale.  Perhaps  Bacon  had  Vincent  in  mind  when  he 
wrote  to  Pope  Clement  that  his  own  scheme  could  only  be  carried 
out  by  the  aid  of  the  Pope  or  of  some  great  prince  like  the  King 
of  France,  for  it  was  to  St.  Louis  that  Vincent  was  indebted  for 
the  unrestricted  use  of  the  royal  library,  containing,  it  is  said, 
some  1,200  manuscripts,  and  for  the  large  staff  of  copyists  and 
helpers  necessary  for  the  completion  of  the  work.  His  method 
is  to  make  extracts  from  the  various  authorities  on  each  subject, 
and  when  necessary  to  add  a  few  remarks  of  his  own.  It  has 
been  computed  that  he  quotes  from  some  450  writers  by  name, 
some  of  whom  we  only  know  by  his  extracts. 

The  Speculum  Naturale  is  divided  into  32  books  and  3,718 
chapters,  and  is  intended  to  be  a  full  description  of  all  created 
living  beings,  from  angels  down  to  fishes  and  plants.  Book  15, 
for  example,  treats  of  astronomy  and  the  calendar  ;    books  23  to 


I 


SCIENCE  IN   THE  THIRTEENTH  CENTURY        137 

27  deal  with  the  psychology,  physiology,  and  anatomy  of  man. 
In  book  6,  cap.  7,  the  question  is  discussed  as  to  what  would 
happen  if  a  stone  were  dropped  down  a  hole  passing  through  the 
centre  of  the  earth,  and  he  decides  that  it  would  stay  there. 
The  Speculum  Doctrinale  treats  of  sciences  and  arts,  beginning 
with  the  trivium,  ethics,  the  economic  arts,  housekeeping,  and 
agriculture,  and  so  on.  The  eleventh  book  treats  of  the  mechanical 
arts,  which  include  architecture,  navigation,  alchemy,  and  metal- 
lurgy, weaving,  smith-work,  commerce,  and  hunting.  Books  12 
to  14  deal  with  medicine,  theoretical  and  practical,  and  book  16 
with  mathematics.  It  is  a  most  useful  summary  of  the  knowledge 
and  belief  of  the  time.  The  Speculum  Historiale  is,  as  its  name 
implies,  a  gossipy  abstract  of  the  history  of  the  world. 

Another  encyclopaedia,  the  most  popular  of  all,  was  the  De 
Proprietatibus  Rerum  of  Bartholomew  Anglicus,  a  Franciscan  friar, 
in  nineteen  books.  It  is  of  the  same  general  character  as  the 
Speculum  Doctrinale,  but  shorter.  It  exists  in  hundreds  of  manu- 
scripts and  several  early  translations  were  made,  while  its  popu- 
larity in  the  early  days  of  printing  was  very  great.  It  appears 
to  have  been  written  somewhere  about  1250,  for  use,  not  in 
University  circles,  but  among  the  general  body  of  friars.  The 
taste  for  encyclopaedic  manuals  spread  to  the  laity,  and  we  have 
a  number  of  compositions  in  the  vulgar  tongue  such  as  Uimage 
du  monde  of  Gautier  de  Metz,  written  about  1245,  treating  of 
cosmogony,  astronomy,  and  geography,  and  the  Fontaine  de. 
toutes  sciences — a  dialogue  between  King  Boetus  and  the  philo- 
sopher Sidrach  on  things  in  general — written  a  little  earlier.  The 
Tresor  of  Brunetto  Latini,  written  in  French  about  1265,  was 
a  book  of  a  superior  sort,  with  as  wide  a  range. 

Bacon  after  these  years  of  study,  after  repeated  entreaties 
from  his  friends,  and,  it  may  be,  criticisms  from  opponents, 
determined  in  his  turn  on  the  composition  of  an  encyclopaedia 
which  was  to  be  a  compendium  of  real  knowledge,  not  a  com- 
mentary on  the  works  of  Aristotle  or  on  the  compilations  of  other 
and  lesser  minds  than  his.  The  great  work  was  to  be  founded 
on  a  reasoned  scheme  of  mental  progress,  leading  up  to  the 
supreme  science  of  the  mind,  for  him  as  for  every  one  else  in 
that  century,  the  science  of  theology. 

The  scheme  of  his  great  encyclopaecUa,  as  he  conceived  it, 
included  four   principal   divisions  :     the   first   volume   comprised 


y 


i;{s  KOCKi:    I^ACON   AND  THK  STATK   OF 

({ramiiiiir  and  l^ogic,  tlic  second  Matliematics,  tlu;  tliij'd  Natural 
ScioiH'c  (IMiysics  and  Kx peri  mental  Science),  the  fourth  Meta- 
])hysies  and  Morals.  He  worked  at  this  scheFiie  niitiJ  his  task 
was  arrested  by  liis  conckMunation  in  1277,  only  hn^aking  otV 
durinti;  the  year  (Unvoted  to  tiie  eompikition  of  th(^  (/pan  Maiu8, 
the  ()i>iis  Minus,  and  tiie  OpuH  Tcrtium^  much  of  tliese  works 
being  obviously  composed  of  material  ready  to  hand.  He  seems 
to  have  worked  at  tliem  in  a  desultory  way,  writing  now  on  one 
subject  now  on  another.  'Aliqua  capitula  de  diversis  materiis', 
'  nihil  continuum  est'  are  his  words.  This  ac(;ounts  for  the  great 
number  and  diversity  of  the  smaller  works  that  y)ass  under  his 
name,  destined  to  take  their  place  in  a  larger  frame,  and  often 
unrelated  to  their  felloA\'s.  Attempts  have  obviously  been  made 
since  his  death  to  effect  this  synthesis  ;  the  fine  Royal  MS8.  of 
Bacon  have  })een  through  the  preliminary  stages  of  such  an 
attempt.  The  Oxford  MS.  of  the  Opus  Mains  is  evidently  an 
aggregation  of  several  tractates  to  the  original  work,  and  the 
Mazarine  MS.  of  the  Cotmnunia  Naluralium  offers  undoubted 
proof  of  having  been  made  up  at  the  end  of  the  fourteenth 
century  from  a  number  of  independent  fragments  written  for 
the  Opus  Teriium,  and  added  to  the  work  as  it  left  the  pen  of 
Bacon. 

The  first  volume  of  this  encyclopaedia  has  not  been  handed 
down  to  us  in  any  complete  form.  Several  fragments  of  it  remain  : 
a  nearly  complete  Greek  grammar,  a  fragment  of  a  Hebrew 
grammar,  a  Summa  grammatice,  and  the  tract  published  by 
Brewer  under  the  title  Compendium  Studii  Philosophiae.  Most  of 
them,  in  the  form  we  have  them  at  any  rate,  appear  to  have  been 
written  after  1267,  though  a  part  of  what  we  find  concerning 
Grammar  and  Logic  in  the  Opus  Tertium  was  probably  taken 
from  pre-existing  fragments.  Bacon  returns  to  the  subject  in  his 
latest  work  the  Compendium  Studii  Theologie,  written  in  1292. 

The  second  volume  was  intended  to  deal  with  Mathematics, 
pure  and  applied,  of  w4iich  nine  divisions  were  recognized  at  the 
time,  five  speculative  and  four  operative.  This  division  is  due  to 
Alfarabi  ;  he  divides  geometry,  arithmetic,  astronomy  (to  use  our 
modern  nomenclature),  and  music  into  two  sections  each,  theoretical 
and  applied,  and  precedes  them  by  a  general  study  of  principles 
'  de  communibus  mathematice  '.  We  have  a  part  of  this  treatise 
written  before  1267,  and  a  later  and  enlarged  form  of  it  written 


SCIENCE  IN  THE  THIRTEENTH  CENTURY       139 

some  time  after,  together  witli  some  shorter  additional  tracts  on 
Geometry.    Astronomy  was  relegated  to  the  third  volume. 

The  third  volume  dealt  with  Natural  Philosophy,  the  modern 
Physics.  It  was  intended  to  include  a  treatise  on  the  first  principles 
of  physics,  the  nature  of  rest  and  motion,  of  the  four  elements, 
of  the  theory  of  compounds  both  inanimate  and  animate,  of 
generation  and  corruption,  alteration,  growth,  and  diminution. 
After  this  he  proposed  to  treat  of  seven  special  sciences  :  Per- 
spective, Astrology,  the  Science  of  Weights,  Alchemy,  Agriculture, 
Medicine,  and  Experimental  Science.  His  scope  is  fully  explained 
in  the  surviving  parts  of  this  volume,  two  forms  of  which  exist, 
one  written  before  1267,  the  other  after.  We  have  in  addition  to 
those  parts  formally  included  in  this  volume  a  number  of  detached 
works,  which  would  naturally  fall  into  their  place  in  the  scheme, 
on  Alchemy,  Medicine,  and  Experimental  Science. 

The  fourth  volume  of  the  Compendium  dealt  with  Metaphysics 
and  Morals.  Of  this  we  have  a  number  of  detached  parts,  a 
separate  treatise  on  the  lines  of  the  Metaphysics  of  Avicenna,  and 
a  treatise  on  the  propagation  of  force  treated  mathematically, 
which  has  been  printed  with  the  Opus  Maius.  There  is  no  doubt 
but  that  he  had  completed  a  part  of  his  treatment  of  the  subject 
long  before  1266,  and  two  important  treatises  wTitten  at  this 
period,  showing  the  development  of  his  theories,  are  still  unprinted. 
A  number  of  references  to  this  work  are  to  be  found  in  the  Opus 
Maius.  The  Morals  would  probably  correspond  largely  to  the 
seventh  part  of  that  work. 

Not  only  had  this  great  encyclopaedic  compendium  been 
undertaken,  but  Bacon  had  given  considerable  attention  to 
a  matter  which  was  becoming  rather  urgent,  the  reform  of  the 
Calendar.  The  slightest  knowledge  of  the  beginnings  of  our  history 
will  remind  us  of  the  importance  attached  by  early  Christianity 
to  the  observance  of  Easter  on  the  proper  date.  By  the  middle 
of  the  thirteenth  century  the  Julian  Calendar  had  amassed  so 
great  an  error  that  it  was  perfectly  possible  that  Easter  might 
be  celebrated  a  month  later  than  the  date  on  which,  according 
to  the  spirit  of  the  rule,  it  should  fall. 

Two  works  of  Bacon  on  the  subject  are  known.  The  large 
de  Computo  is  an  historical  and  general  treatise  on  the  various 
divisions  of  time  and  on  the  methods  of  using  tables  for  the 
calculation   of  festivals   or  reducincj   Arabic   to   Christian   dates. 


140  HCKiKll   HA(T)N   AND  THE  STATK  OF 

Tliat  iiuliidcd  in  tiic  Oints  MaiuH  is  more  controversial.  It  exposes 
llic  fiuilts  oi  the  Julian  Calendar,  by  the  o])servance  of  which 
Easter  is  celebrated  on  the  wrong  date  in  tlie  tliird  and  fourte>enth 
years  of  tlie  lunar  cycle.  He  points  out  th(^  superior  advantage 
of  using  tlie  Aral)  system  of  30  years  of  12  lunations,  making 
10,631  days,  or  of  adopting  the  Hebrew  system  which  is  nearly 
the  same.  In  this  attack  on  the  (^stabhshed  order  of  things  Bacon 
stands  nearly  alone  in  his  time ;  and  thougli  his  arguments 
were  rei)eated  in  the  next  two  centuries  several  times,  it  took 
three  hundred  years  to  effect  this  simple  reform. 

In  connexion  with  his  study  of  this  work  Bacon  seems  to  have 
written  several  treatises,  one  de  Temporihus  which  once  existed 
in  the  Austin  Friars'  Library  at  York  but  is  now  lost ;  the  long 
work,  the  Computus,  written  in  1263-4  ;  and  a  shorter  treatise 
dealing  with  times  and  seasons  in  1266.  He  sums  up  his  arguments 
in  the  fourth  part  of  the  Opus  Maius,  returning  to  the  point  in 
the  Opus  Tertium. 

The  turning-point  in  Bacon's  career  was  in  1266.  Probably 
about  1264,  Cardinal  Guy  de  Foulkes  heard  of  Bacon's  writings 
from  a  clerk  in  his  service,  Raymond  of  Laon,  whom  he  com- 
missioned to  obtain  them.  In  1265  the  Cardinal  became  Pope 
under  the  title  of  Clement  IV.  In  March  1266  Sir  William  Bonecor 
was  sent  by  Henry  III  on  a  special  mission  to  the  new  Pope,  and 
he  seems  to  have  carried  with  him  a  communication  from  Roger 
Bacon,  which  Professor  Little  conjectures,  with  some  probability, 
to  have  been  the  Metaphysica  de  viciis  contractis  in  studio  theologi. 
On  receiving  this  the  Pope  replied  in  a  letter,  first  printed  by 
Martene,  asking  him  to  indicate  the  remedies  he  would  i^ropose 
for  the  evils  he  had  pointed  out,  and  ordering  him  to  send  the 
wTitings  he  had  previously  asked  for,  secretly  and  without  delay, 
any  Constitution  of  his  Order  to  the  contrary  notwithstanding. 
This  letter  is  dated  June  22,  1266. 

As  a  result  of  this  Papal  command  we  possess  the  most  widely 
known  of  Bacon's  works  :  the  Opus  Maius — a  preliminary  work 
he  calls  it — a  '  tractatus  preambulus  '  in  contradistinction  to  liis 
great  encyclopaedia,  and  with  it  three  treatises,  summaries  and 
supplements  to  it :  the  introductory  letter  and  summary  found 
in  the  Vatican  Library  by  Cardinal  Gasquet ;  the  Opus  Minus — 
a  summary  wdth  additional  remarks  on  the  causes  of  error  in  the 
church.  Biblical  textual  criticism,  and  a  short  theory  of  alchemy  ; 


SCIENCE  IN  THE  THIRTEENTH  CENTURY        141 

and  the  Opus  Tertium,  a  work  of  which  the  exact  size  is  still 
uncertain,  which  was  probably  never  completed.  The  Opus  Maius 
and  Opus  Minus,  with  some  other  treatises,  were  probably  sent 
to  the  Pope  early  in  1268,  but  as  he  died  in  the  same  year,  and 
his  successor  was  not  elected  till  1271,  no  answer  was  received  by 
Bacon  and  no  result  followed  from  them. 

Of  the  work  of  the  succeeding  years  there  is  little  to  tell. 
Bacon  seems  to  have  worked  on  his  Compendium,  to  have  com- 
pleted his  introduction  to  the  Secretum  Secretorum,  and  about 
1272  to  have  written  the  work  published  by  Brewer.  He  was 
evidently  in  residence  at  Oxford  at  this  period,  to  which  may  be 
referred  the  legends  as  to  his  construction  of  magical  mirrors  and 
perspective  glasses  referred  to  in  the  foundation  for  Greene's  play 
of  Friar  Bacon  and  Friar  Bungay.  He  was  imprisoned  in  1278  by 
the  Minister-General  of  his  Order  for  some  '  suspected  novelties  ', 
and  it  is  believed,  on  no  definite  grounds,  that  he  remained  in 
prison  till  1292,  the  date  of  composition  of  his  last  fragment,  the 
Compendium  Studii  Theologie,  published  by  Rashdall— a  work 
which  was  intended  to  be  completed  in  seven  parts,  including 
much  of  his  earlier  writing. 

It  would  be  wrong  to  infer,  because  his  name  is  rarely  quoted 
in  the  few  works  of  the  half-century  succeeding  him,  that  his 
influence  was  negligible.  Nearly  all  the  manuscripts  of  his  works 
we  possess  must  have  been  written  after  his  death.  They  range 
in  date  from  the  end  of  the  thirteenth  century  to  the  middle  of 
the  fifteenth,  and  their  form  attests  a  constant  attempt  to  edit  and 
rearrange  them  according  to  the  author's  intention.  In  the  face 
of  his  express  condemnation,  the  wish  that  his  '  dangerous  teaching 
might  be  completely  suppressed',  the  absence  of  his  name  is  easily 
understood,  but  the  influence  of  his  thought  is  clearly  discernible 
in  Oxford  teaching  up  to  the  time  of  the  Renaissance. 

In  estimating  Bacon's  position  among  the  men  of  his  own  time 
it  is  important  to  remember,  first  of  all,  the  complete  originality 
of  his  scheme.  His  great  work,  unfinished  though  it  most  probably 
was,  and  almost  beyond  the  powers  of  any  one  unaided  scholar 
to  complete,  the  Compendium  Studii  Philosophie  or  Theologie, 
as  the  case  may  be,  was  as  distinct  in  kind  as  in  form  from  the 
works  of  his  great  contemporaries.  As  we  have  already  said,  it 
was  an  age  of  encyclopaedias,  but  none  of  them  were  independent 
in  form.     Albert's  life-work  consisted  in  a  series  of  comments  on 


112  llOCKi:    I'.ACOX    AND   THK   STATE   OF 

till'  words  ol  Arintotle,  followin;^  the  order  of  his  text  with  occa- 
sional o.xcnrsiiscs  wlicii  the  subject  .sccincd  to  suggest  them,  but 
breaking  no  new  j^rouiid,  and  niakinj^  no  rcarran^cincnt  of  his 
matter.  The  great  work  of  St.  Thomas  is  (conditioned  by  tlu^ 
Sevtences,  following  its  order  with  more  originality  and  power 
than  Albert,  but,  after  all,  ado|)ting  another  man's  Hcheme.  Hi.s 
physics  are  mere  commentaries  on  the  text  of  Aristotle.  On  the 
other  hand,  the  encyclopaedia  of  X'incent  of  Reauvais  owes  nothing 
of  its  arrangement  to  Aristotle,  and  comparatively  little  to  its 
early  forerunners,  and  was,  so  far,  original.  But  there  its  origin- 
ality ceased  :  it  was  merely  a  collection  of  facts  and  dicta  collected 
from  approved  authors  by  the  industry  of  a  small  college  of  clerks, 
and  arranged  under  convenient  headings.  Jt  added  nothing  to 
human  knowledge,  no  inspiration  for  the  progress  of  thought. 

Bacon's  schematic  arrangement  was  not  only  unparalleled 
among  the  writers  of  his  time  ;  it  was  absolutely  new^  Nothing 
like  it  had  been  devised  since  the  time  of  Aristotle,  and  it  had 
the  advantage  of  not  being  obliged  to  combat  a  large  number  of 
exploded  hypotheses.  The  whole  system  of  human  thought  was 
re-cast,  and  the  plan  simplified  to  an  extraordinary  degree  to  meet 
the  necessities  of  the  age.  It  may  be  that  the  framework  of  his 
scheme  owed  something  to  Al  Farabi's  de  Scienciis,  or  to  Avicenna, 
but  in  its  conception  and  execution  its  originality  is  manifest. 
His  plan  has  already  been  described,  its  execution  was  to  be 
marked  by  the  most  rigorous  economy.  Everything  superfluous 
or  unnecessary  to  the  development  of  the  argument  was  to  be  cut 
away  ;  all  the  excrescences  which  dialectical  skill  had  embroidered 
on  the  simplest  notions  were  to  be  discarded.  Bacon  did  not 
exclude  the  notion  of  special  treatises  ancillary  to  the  main  lines 
of  his  course,  but  he  did  not  regard  them  as  necessary  to  every 
pupil.  He  thought  it  more  necessary,  for  example,  that  the  results 
of  geometry  should  be  known  as  a  whole,  than  that  the  pupil 
should  be  able  to  prove  the  fifth  proposition  and  be  ignorant  of 
the  sixth  book  of  Euclid. 

The  foundation  of  his  system  was  laid  on  an  accurate  study 
of  language :  '  Notitia  linguarum  est  prima  porta  sapientie.' 
Latin,  of  course,  was  taken  for  granted  like  Enghsh  or  French 
(is  it,  by  the  way,  noticed  that  Enghsh  is  spoken  bj^  a  Norman 
family  as  early  as  1270  ?).  But  Latin  alone  was  no  sufficient  key 
to  the  treasury  of  knowledge  :    its  vocabulary  was  too  limited, 


SCIENCE   IN  THE  THIRTKENTH   CENTURY        143 

the  masterpieces  of  tlie  world's  teaching  were  either  not  translated 
into  it,  or  were  so  badly  translated  that  they  were  wholly  mis- 
leading to  such  teachers  and  taught  as  attempted  to  profit  by 
them.  We  need  not  labour  the  point  as  Bacon  had  to  do  ;  the 
fact  remains  that  no  mediaeval  translation  of  Aristotle  or  his  com- 
mentaries is  now  consulted,  except  as  a  curiosity.  Bacon's  study 
of  languages,  Grammatica,  included  not  only  the  modern  Philology 
but  also  a  strictly  utilitarian  Logic  and  Dialectic,  sufficient  for 
the  study  of  mediaeval  science  which  was  to  follow  :  '  Grammatica 
et  logica  priores  sunt  in  ordine  doctrine.'  We  have  a  great  part 
of  Bacon's  teaching  on  the  subject,  scattered  over  many  writings. 
His  main  work  was  destructive  ;  the  schools  were  lumbered  with 
inefficient  text-books  and  antiquated  errors.  After  that  came 
reconstruction,  '  secundum  linguas  diversas  prout  valent  immo 
eciam  necessarie  sunt  studio  Latinorum  *  ;  Greek,  Hebrew,  and 
Arabic.  He  recognized  three  stages  in  the  knowledge  of  languages, 
looking  at  the  question  from  the  point  of  view  of  actual  life,  not 
of  a  teacher.  The  first  was  that  of  a  man  who  recognizes  that 
a  word  is  Greek,  Hebrew,  &c.,  can  read  it  and  even  pronounce  it, 
knows  approximately  what  grammatical  forms  it  may  take,  and 
so  on  :  something  like  a  man  who  can  read  enough  German  to 
know  the  names  of  the  streets  and  the  directions  on  the  tramcars, 
but  cannot  speak  the  language.  This  is  the  sort  of  knowledge 
of  Hebrew  or  Greek  which  Bacon  pledged  himself  to  impart  in 
three  days,  when  writing  in  his  Opus  Tertmm  and  elsewhere.  The 
second  stage  of  knowledge  was  the  power  to  read  and  understand 
in  an  ordinary  way.  '  Certes,'  he  says,  '  this  is  difficult,  but  not 
so  difficult  as  men  believe.'  His  third  stage  is  only  reached  when 
the  student  can  talk  and  write  and  preach  in  the  foreign  language 
as  in  his  own.  The  only  grammars  actually  preserved  to  our  own 
day  which  have  been  identified  are  the  Greek  and  a  fragment  of 
the  Hebrew.  It  is  doubtful  whether  he  ever  knew  Arabic  or 
composed  a  grammar  of  that  language.  He  certainly  knew 
Chaldaic  enough  to  explain  its  relation  to  and  difference  from 
Hebrew.  His  Greek  Grammar  is  a  very  remarkable  one  for  the 
time,  even  if  it  be  true  that  it  is  founded  on  a  Byzantine  original. 
As  we  have  it,  the  work  is  not  complete,  and  the  study  of  Greek 
made  no  progress  in  this  country  for  nearly  two  centuries  and 
a  half. 

This,  then,  is  his  first  distinction  in  the  study  of  lajiguages, 


141  JIOCJEll   BACON   ANJ)  THK  STATE  OF 

that  \w.  laid  down  the  ])riiicij)lo  that  every  language  lias  an 
ijidividuahty  of  its  own,  and  that  the  grannnar  apjn-opriate  for 
oni)  of  tliem,  say  Latin,  would  not  k^nd  itscilf  to  the  study  of 
another,  sueh  as  Greek.  It  is  a  ])rinei]jle  whieh  way  only  recognized 
in  practiec  towards  the  end  of  the  nineteenth  century,  and  is  still 
disregarded  by  many  writers.  But  he  was  also  distinguished  as 
a  critic. 

All  human  knowledge  was,  in  his  day,  assum(;d  to  lead  up  to 
the  study  of  theology — the  queen  of  sciences.  Whatever  progress 
was  made  on  the  great  hnes  of  modern  thought  was  made,  not 
with  that  aim,  but  with  the  intention  of  facilitating  the  formation 
of  right  conclusions  as  to  the  relation  between  God  and  man. 
If  we  are  to  undervalue  our  predecessors  on  this  account,  we  need 
not  study  the  thought  of  the  Middle  Ages.  Bacon's  criticism  of 
his  contemporaries  was  actuated  by  the  thought  that  they  were 
bad  teachers  because  they  were  insufftciently  taught,  that  they 
taught  in  error  because  they  were  unable  to  test  the  truth  of  the 
maxims  they  repeated.  His  zeal  for  truth,  his  application  of  the 
tests  of  truth,  remain  of  value  if  his  conception  of  the  highest 
truths  no  longer  satisfies  us.  His  criticism  was  applied  to  the 
text  of  the  Vulgate  ;  the  principles  of  textual  criticism  he  laid 
down  are  of  universal  application. 

A  large  part  of  Bacon's  published  work  on  the  subject  is  taken 
up  with  the  proofs  of  the  corrupt  state  of  the  Vulgate  text,  made 
worse  by  the  number  of  correctors,  for  the  most  part  ignorant  of 
both  Greek  and  Hebrew.  More  than  that,  many  of  these  correc- 
tions would  not  have  been  made  if  the  correctors  had  even  con- 
sulted a  good  Latin  grammar.  The  scheme  he  proposes  is  an 
official  attempt  to  restore  the  genuine  text  of  the  Vulgate  as 
issued  by  St.  Jerome  from  a  comparison  of  the  oldest  manuscripts, 
which  were  to  be  collected,  examined,  and  compared,  while  the 
readings  were  to  be  judged  by  the  original  Greek  or  Hebrew  from 
which  St.  Jerome  had  made  his  translation.  Here  for  the  first 
time  in  the  JMiddle  Ages  were  the  true  principles  of  textual 
criticism  laid  down,  principles  valid  for  the  work  of  every  editor 
since  his  time. 

After  the  science  of  language  had  been  thoroughly  mastered, 
so  that  the  student  was  able  to  read  the  principal  documents  of 
scholarship  in  the  original  and  follow  their  train  of  thought, 
Bacon  next  directed  his  attention  to  Mathematics.     As  we  have 


SCIENCE  IN  THE  THIRTEENTH  CENTURY       145 

already  pointed  out,  this  science  was  already  reviving  in  western 
Europe.  In  Italy  Leonardo  Fibonacci  had  published  his  Liber 
Abaci,  Campanus  had  re-edited  Euclid  and  written  on  the  sphere, 
de  Lunis  had  begun  the  study  which  was  to  become  algebra.  In 
France  Alexandre  de  Villedieu  had  written  the  Carmen  de  Algo- 
rismo,  the  popular  treatise  on  Arithmetic  ;  in  Germany  Jordanus 
Nemorarius  on  the  theory  of  numbers,  the  geometry  of  the  sphere 
and  on  triangles ;  while  the  English  John  of  Halifax  wrote  c.  1232 
the  De  sphera  mundi,  the  most  popular  text-book  on  the  subject 
of  the  Middle  Ages,  and  his  Tractatus  de  arte  Numerandi ;  and 
Peckham's  Perspectiva  communis  and  Grosseteste's  semi-mathe- 
matical tractates  were  also  published. 

Bacon's  own  reading,  a,s  evidenced  by  quotations  in  his  Com- 
munia  Mathetnatica,  was  considerable.  Besides  the  general 
scholastic  learning  of  his  day  he  quotes  from  all  the  works  of 
Euclid,  the  Almagest  and  Aspects  of  Ptolemy,  Theodosius  on  the 
Sphere,  Apollonius,  Archimedes,  Vitruvius,  and  Hipparchus. 
Boethius  is  his  main  stand-by.  The  Arabic  writers  were  well 
knoAvn  to  him,  and  early  mediaeval  writers  such  as  Adelard  of 
Bath,  Jordanus,  Anaricius,  Bernelius,  Gebert,  and  others  are  often 
quoted  ;  indeed,  we  learn  of  a  hitherto  unknown  work  by  Adelard 
from  his  writings.  It  would  seem,  however,  that  the  general 
interest  in  mathematics  of  his  time  was  strictly  utilitarian.  '  The 
philosophers  of  these  days,'  says  he,  '  when  they  are  told  that  they 
ought  to  know  perspective  or  geometry,  or  languages,  and  many 
other  things,  ask  derisively,  "  What  good  are  they  ?  "  asserting 
that  they  are  useless.  Nor  will  they  hsten  to  any  account  of 
their  utility,  and  so  they  neglect  and  despise  the  sciences  of  which 
they  are  ignorant.' 

His  own  view  of  the  value  of  mathematics  in  education  was 
a  very  high  one.  Like  Plato,  he  saw  in  it  the  master  key  to  all 
correct  reasoning  and  all  progress  in  knowledge.  '  Mathematica 
est  omnino  necessaria  et  utilis  aliis  scientiis.'  '  Impossibile  est 
res  huius  mundi  sciri,  nisi  sciatur  mathematica.'  '  Oportet  ut 
fundament  a  cognitionis  in  mathematica  ponamus.'  It  was  not  so 
much,  mathematics  for  its  own  sake,  as  mathematics  a  handmaid 
to  the  natural  sciences  and  theology.  We  have  already  referred 
to  his  classification  of  the  subject  as  speculative  and  practical, 
following  a  study  of  the  elements  of  the  science.  His  remaining 
work  is  largely  taken  up  by  discussions  of  the  meaning  of  con- 


\^ 


146  KOCJFJl    BAC^ON   AND  THK  STATE  OF 

timiity,  iiiliiiity,  (liniciisioiis,  axioms,  postulates,  dc^fiiiitions,  and 
the  like,  and  he  spends  imicli  Wnw,  on  the  various  ratios,  aritli- 
DK^tical,  i^coinc't lical,  and  liaiinonical.  But  in  puro  niatliciiiatics 
lie  was  not  an  ori^^iiiator,  lie  made  no  discoveries  in  geometry  or 
the  theory  of  numbers  :  his  title  to  remembrance  as  a  mathe- 
matician is  his  sym])athy  with  it,  his  wide  knowledge,  and  his 
insistence  on  its  value  as  the  foundation  of  a  li})eral  education. 

Bacon's  work  on  optics  was  really  a  |)art  of  a  larger  scheme 
in  his  own  mind — a  study  of  the  ])ro])agation  of  force  at  a  dis- 
tance. This  he  treated  geometrically  and  used  one  variety  of 
force  as  an  example  which  was  susceptible  of  measurement — light. 
Thus  is  explained  the  emphasis  laid  on  the  science  of  optics,  or 
perspective,  as  he  called  it.  His  main  treatises  on  it,  the  Per- 
spective and  the  Multiplication  of  Species,  were  written  before  the 
Ojjus  Maius.  The  scheme  of  the  Perspective  was  not  entirely  new, 
of  course  ;  it  had  to  include  much  that  had  been  treated  by  his 
predecessor  i\lhazcn,  and,  as  a  summary,  to  omit  man}'  of  his 
detailed  geometrical  extensions  of  theorems.  But  on  the  other 
hand,  it  carried  on  the  science  a  considerable  way,  as,  for  example, 
by  proving  that  a  concave  spherical  mirror  would  bring  the 
reflected  rays  from  different  parts  of  its  surface  to  a  focus  on 
different  parts  of  its  axis,  and  that  to  obtain  a  single  focus  the 
mirror  must  have  a  surface  produced  by  the  rotation  of  a  parabola 
or  hyperbola. 

His  study  of  the  theory  of  optics  went  hand  in  hand  with 
practical  work  ;  he  caused  to  be  constructed  concave  mirrors  for 
use  as  burning-glasses,  time  after  time,  remarking  on  the  diminish- 
ing cost  as  the  craftsman  grew  more  skilful ;  he  was  familiar  wdth 
the  use  and  properties  of  a  convex  lens  both  for  magnification  of 
objects,  i.e.  the  simple  microscope,  and  as  a  burning-glass  ;  and 
there  is  every  reason  to  suppose  that  he  was  acquainted  with  the 
combination  of  lenses  which  makes  up  the  telescope,  though  he 
only  used  it  for  terrestrial  objects  and  did  not  make  it  portable. 

It  is  this  combination  which  lies  at  the  base  of  the  legend  of 
Bacon  and  Bungay's  magic  mirror  which  had  growii  up  b}^  1385, 
'  Friar  Roger  Bacon  took  such  delight  in  his  experiments  that 
instead  of  attending  to  his  lectures  and  writings  he  made  two 
mirrors  in  the  University  of  Oxford  :  by  one  of  them  you  could 
light  a  candle  at  any  hour,  day  or  night ;  in  the  other  you  could 
see  what  people  were  doing  in  the  uttermost  parts  of  the  earth. 


SCIENCE  IN  THE  THIRTEENTH  CENTURY        147 

The  result  was  that  the  students  either  spent  their  time  in  h^rhtiiig 
candles  at  the  first  mirror  instead  of  studying  books,  or,  on  looking 
into  the  second  and  seeing  their  relations  or  friends  dying  and 
lying  ill,  left  Oxford  to  the  ruination  of  the  University — and  so 
both  mirrors  were  broken  by  the  common  counsel  of  the  Univer- 
sity.' This  legend  refers  evidently  to  the  burning-glass  and  tele- 
scope. The  latter  is  shown  to  have  existed  by  a  statement  printed 
in  1579  that  Leonard  Digges,  then  dead,  '  was  able  by  Pers])ective 
Glasses  duely  situate  upon  convenient  Angles,  in  sucli  sort  to 
discover  every  particularitie  of  the  Countrie  round  about,  where- 
soever the  Sunne  beames  might  pearse  .  .  .  which  partly  grew  by 
the  aid  he  had  by  one  old  written  book  of  the  same  Bakon's 
experiments,  that  .  .  .  came  to  his  hands  '.  This  work  of  Bacon's 
is  no  longer  known  to  exist. 

We  have  already  spoken  of  his  devotion  to  Astronomy  in  the 
modern  sense  of  the  word.  His  account  of  the  science  in  the 
Opus  Mains,  the  De  Celestibus,  and  the  fragment  of  the  Opus 
Tertium  published  by  Duhem,  not  only  shows  that  he  was  abreast 
of  the  best  work  of  his  time,  but  also  forms  the  best  epitome  of 
the  state  of  knowledge  at  the  day.  His  continual  labour  in  the 
construction  of  astronomical  tables  bore  fruit  in  his  attempt,  at 
the  reformation  of  the  calendar,  of  which  we  have  given  some 
account.  His  work  on  Chronology,  sacred  and  secular,  is  closely 
connected  with  this  subject. 

Bacon  also  takes  rank  as  one  of  the  earliest  mediaeval  \mters 
on  Geography,  and  part  of  his  treatise  was  reprinted  for  the  first 
time  by  Purchas  in  1625  from  the  Opus  Mains  manuscript.  His 
study  was  founded  in  the  first  place  on  Ptolemy,  checked  by 
modern  travel,  and  his  first  consideration  is  an  approximate 
determination  of  the  relative  amounts  of  land  and  water  on  the 
globe.  It  was  a  passage  of  this  part  of  his  work  which  had 
a  leading  part  in  deciding  Columbus  to  make  an  attempt  to  reach 
the  Indies  by  the  Atlantic  route,  as  shown  by  his  letter  from  Haiti 
to  Ferdinand  and  Isabella.  Bacon's  description  covers  the  known 
world  with  the  exception  of  western  Europe,  and  he  insists  on 
the  habitability  of  the  earth  south  of  the  equator,  and  on  the 
extension  of  Africa  to  the  south.  We  have  only  to  comj^are  this 
treatise  with  Albert's  De  natura  locorum  to  understand  the  great 
advance  Bacon  has  made. 

His  position  in  the  history  of  Chemistry  has  yet  to  be  fully 


148  ROOKR    BArON   AND  THE  STATK   OK 

investigated.  I'iie  very  large  number  of  alchemical  tracts  which 
pans  under  his  name  show  that  his  influence  upon  the  students 
of  the  next  century  wa-s  very  great.  We  are,  luiturally,  at  a  loss 
to  do  more  than  form  a  reasonable  conjecture  as  to  the  extent 
of  his  practical  acquaintance  with  the  operations  of  chemistry  or 
alchemy,  since  his  \\Titings  are  devoted  rather  to  theoretical  than 
practical  considerations.  There  was,  of  course,  a  large  number 
of  industries  which  depended  on  chemical  reactions  for  their 
/  methods  ;    brewing,  dyeing,  enamel-making,  glass-making,  metal- 

^^^  liirgy,  lime-works,   are  but  a  few  examples  ;    but  the  eyes  of 

inquirers  were  rarely  turned  towards  these,  and  a  superficial 
reason  was  given  for  the  effects  produced.  What  was  really  being 
sought  by  students  was  the  general  formula  of  the  universe, 
adopting  more  modern  terms,  its  integral  equation,  which,  once 
found,  would  resolve  any  particular  case  by  substituting  suitable 
values  for  its  constants.  Whether  he  had  made  up  his  mind  as 
to  the  existence  of  a  universal  primary  matter  in  our  modern 
sense,  taking  up  the  properties  which  made  it  a  distinct  material, 
is  doubtful.  The  theories  he  held  as  to  the  action  of  the  celestial 
bodies  on  this  earth  swayed  him  first  one  way,  then  another, 
while  the  dicta  of  Aristotle  and  Avicenna  that  no  change  can 
happen  '  nisi  fiat  resolutio  ad  materiam  primam ',  which  he 
accepted  without  questioning,  led  him  towards  its  acceptance. 
His  doctrine  of  the  multiplication  of  species  was  one  of  the  most 
fruitful  in  his  theory  of  alchemy.  Just  as  celestial  fire  produced 
fire  by  means  of  a  lens,  so  the  celestial  bodies  might  act  on 
a  suitable  primary  matter  to  produce  their  cognate  metal,  if  their 
influence  were  as  great.  The  science  of  weights  was  a  branch  of 
alchemy,  because  what  distinguished  the  four  elements  in  change- 
able matter  from  those  in  the  super-celestial  regions  was  their 
combination  with  the  quaUties  of  heaviness  and  lightness. 

Alchemy,  according  to  Bacon,  was  either  speculative  or 
practical.  Speculative  or  theoretical  alchemy  treats  of  the  genera- 
tion of  materials  from  their  elements  inanimate  or  animate.  His 
list  of  inanimate  things  comprises  metals,  gems,  stones,  colours, 
salts,  oils,  bitumen,  &c.  ;  his  animate  things  include  vegetables, 
animals,  and  men.  Alchemy  was  for  him  linked  with  Physics 
and  Medicine  in  a  chain  of  development.  Among  the  treatises 
wliich  give  us  the  clearest  views  of  his  thought  are  the  Opus 
Minus  fragments  and  the  Opus  Tertium :    by  these  the  others 


SCIENCE  IN  THE  THIRTEENTH   CENTURY         149 

are  to  be  tried  and  accepted  or  rejected.  A  striking  example  of 
the  effect  of  his  teaching  is  to  be  found  in  the  treatise  De  lapide 
philosophicif  attributed  to  St.  Tiiomas  Aquinas  but  really  written 
by  Fr.  Thomas,  chaplain  to  Robert,  son  of  Charles  of  Anjou, 
in  1296. 

Nothing  has  yet  been  said  of  his  relation  to  the  peculiar  science 
of  his  scholastic  contemporaries — speculative  philosophy.  This 
was  almost  a  creation  of  his  own  time,  due  to  the  fuller  study  of 
Aristotle  now  possible.  The  meaning  of  matter,  form,  and  sub- 
stance, the  struggle  between  realist  and  nominalist,  the  question 
of  species  and  individual,  all  involved  questions  of  the  highest 
religious  importance,  pantheism  or  theism.  Here  Bacon,  leading 
the  Oxford  schoolmen  of  later  years,  rejects  much  of  the  con- 
troversy as  useless.  There  is  no  answer  to  the  question  what 
causes  individuality  or  what  universality  :  God  makes  things  as 
their  nature  requires.  The  second  part  of  the  Communia  Natura- 
lium  alone  is  quite  enough  to  place  Bacon  in  a  high  place  among 
mediaeval  schoolmen  :  its  clear  treatment  shows  solid  thinking 
as  well  as  sound  criticism. 

Looking  back  on  the  whole  activity  of  this  remarkable  scholar 
we  may  try  to  sum  up  the  interest  he  has  for  the  modern  world. 
Perhaps  to  himself  the  question  would  have  been  otiQ§.e  :  he  was, 
like  many  men  of  science  to-day,  prepared  to  accept  results  and 
methods  without  lingering  over  the  history  of  how  they  came 
into  being.  But  on  the  other  hand,  to  the  large  and  increasing 
number  to  whom  the  history  of  scientific  thought  and  method  is 
often  almost  as  important  as  its  results,  Roger  Bacon  stands  out 
prominently  as  the  first  English  leader  of  scientific  thought.  More 
still,  he  has  the  special  English  quality  of  fighting  a  lone  battle 
for  his  views,  unsupported  as  he  was  by  his  own  order,  attacking 
its  opponent's  chiefs,  and  remaining  unshaken  to  the  end.  His 
works,  though  not  entirely  neglected,  have  usually  been  treated  as 
curiosities,  while  those  of  his  two  great  contemporaries  have  been 
held  in  reverence  for  centuries,  and  even  to-day  are  receiving  the 
full  honours  of  scholarship  in  new  editions  from  the  manuscripts. 
The  publication  of  his  remains  would  be  invaluable,  if  only  as 
marking  the  development  of  a  mediaeval  thinker,  ranging  as  they 
do  over  a  period  of  forty  years'  activity  from  his  early  lectures  at 
Paris.  In  them  we  can  trace  the  process  of  emancipation  from 
established  ruts  of  thought  and  the  entrance  of  new  conceptions. 

2391  T. 


150  ROGER    liACON 

We  ciin  lollow  liis  attempts  to  make  a  theory  to  explain  the 
whole  body  of  natural  phenomena,  the  gradual  elaboration  of 
a  mathematical  theory  of  action  at  a  distance,  which,  unfruitful  at 
the  moment,  reap]iears  in  a  fuller  form  in  )nodern  science.  We' 
see  him  as  a  pioneer  of  textual  criticism,  a  critic  of  estabhshed 
authorities  in  whom  the  spirit  of  Reynard  the  Fox  and  the  Fahlavx_ 
is  incarnated,  a  critic  of  received  doctrines  who  applies  to  them 
in  an  ever-increasing  degree  the  test  of  common  sense  and  experi- 
ment. The  work  of  such  a  one  should  be  available  to  all  the 
world  of  scholars  :  more  than  half  of  it  in  bulk  is  still  locked  up 
in  single  manuscripts  difficultly  legible  and  almost  inaccessible. 


11 


^^^ 


—        y 


w 
H 

.< 


^-'■-'■;^c:<i:i 


ir,     " 


LEONARDO   AS    ANATOMIST 

By  H.  Hopstock 

translated  from  the  norwegian  by  e.  a.  fleming 

Wisdom  is  the  daughter  of  Experience, 
Truth  is  only  the  daughter  of  Time. 

Leonardo. 

The  greater  part  of  Leonardo  da  Vinci's  anatomico-physio- 
logical  manuscripts  are  preserved  at  Windsor.  Sixty  leaves  of 
these,  with  altogether  about  400  drawings,  have  been  published  in 
facsimile  with  a  diplomatic  transcription  and  French  translation 
as  Fogli  A,  Paris,  1898,  and  Fogli  B,  Turin,  1901,  the  two  together 
constituting  the  edition  of  the  Russian  Sabachnikoff  and  the 
Italian  Piumati,  with  a  preface  by  the  French  anatomist  Duval. 
The  remaining  Windsor  manuscripts  of  129  leaves,  with  altogether 
about  1,050  drawings,  have  been  published  in  facsimile  with  diplo- 
matic transcription  and  English  and  German  translations  as  the 
six  volumes  of  the  Quaderni  d^Anatomia  by  Vangensten,  Fonahn, 
and  Hopstock,  Christiania,  1911-16. 

The  facsimiles  in  the  Fogli  show  Leonardo's  drawings  without 
colour.  The  Quaderni  contain  an  exact  reproduction  of  his 
manuscripts,  showing  the  various  tones  of  the  paper,  and  the 
shades  of  the  red  chalk,  pencil,  ink,  and  other  pigments  which  he 
used.  The  drawings  and  text  of  the  Fogli,  with  very  few  excep- 
tions, treat  of  anatomical  and  physiological  questions  only.  Of 
the  Quaderni,  three-quarters  are  concerned  with  these  subjects, 
whilst  a  quarter  of  the  drawings,  and  much  of  the  text,  deals 
with  other  matters,  especially  mathematics,  geometry,  phj^sics, 
and  art. 

The  Quaderni  show  more  clearly  than  the  Fogli  the  manner 
in  which  Leonardo  carried  out  his  anatomical  researches,  and  the 
period  during  which  these  developed.  The  pages  of  the  Fogli, 
on  the  whole,  reveal  Leonardo  as  an  independent  and  confident 
anatomist,  especially  ^vith  regard  to  his  drawings.  These  manu- 
scripts must  therefore  have  been  written  in  his  later  years.  They 
discuss  osteology,  myology,  the  peripheral  nervous  system,  the 

L  2 


152  LKOXAltDO   AS   ANATOMIST 

hloofl-vosscls,  the  .Llxioiiiiiuil  organs,  and  .so  on,  all  in  a  com- 
paratively liiicnt  and  clear  style,  'i'lie  (^iiadejiii,  on  the  otiier 
hand,  cover  a  very  lontz;  period  in  Leonardo's  investigations, 
from  his  very  first  anatomical  studies  in  1481)  up  to  iiis  latest 
years.  His  lan<!;iiaii;e  in  tlu?  Quaderni  is  conse(|ii('iitly  not  infrc- 
(lucjitiy  uncouth  and  involved,  so  that  it  is  dijlicult  to  make  out 
the  meaning.  The  style,  however,  is  extremely  characteristic 
throughout. 

Leonardo  a])p,ireiitly  at  first  made  extensive  use  of  old  ana- 
tomical literature  and  diagrams.  He  attempted  to  elucidate  and 
explain  these,  but  as  his  authorities  were  inaccurate,  so  also  were 
his  delineations  indefinite  and  clumsy.  He  then  began  to  pursue 
his  own  studies,  cautiously  and  tentatively  at  first,  and  then  with 
more  ease  and  definite  purpose,  until  at  last,  emancipated  from 
tradition,  he  stands  forth  as  what  he  is,  a  great  biologist. 

He  carried  out  his  own  precept  to  dissect  the  same  part 
repeatedly.  This  is  evident  from  the  Quaderni,  where  sometimes 
on  the  same  page,  sometimes  on  different  folios,  numerous  sketches 
appear  of  the  same  organ,  sketches  which  show  his  progress  from 
a  hesitating  student  to  a  confident  and  independent  investigator. 

The  Quaderni  show  also  that  Leonardo  dissected  animals. 
He  has  in  part  applied  these  discoveries  to  man,  and  it  is  evident 
from  some  embryological  drawings  and  sketches  of  the  processes 
of  reproduction  that  there  are  instances  in  which  he  rested  satisfied 
with  these,  though  for  the  most  part  he  finally  x^ortrays  conditions 
as  they  occur  in  man.  Yet  strange  to  say,  in  the  midst  of  his 
best  tojDographical  work,  he  occasionally  takes  an  illustration  of 
a  single  organ  from  an  animal ;  it  would  seem  that  he  has  done 
this  but  as  a  trial  or  experiment,  for  in  other  cases  the  organ 
is  correctly  reproduced. 

Certain  departments  of  anatomy,  only  lightl}^  touched  on  in 
the  Fogli,  are  made  the  subject  of  careful  stud}'  in  the  Quaderni. 
Such,  for  example,  are  the  study  of  embryology,  the  structure  of 
the  generative  organs,  the  form  and  functions  of  the  diaphragm, 
the  lungs,  the  brain  cavities,  and  especialh^  the  heart  and  vascular 
system,  as  well  as  surface  anatomy,  and  the  study  of  proportion. 
It  is  indeed  evident  from  the  Quaderni  that  Leonardo  undertook 
his  dissections,  not  only  in  order  to  obtain  anatomical  data,  but 
also,  with  the  aid  of  this  knowledge,  to  arrive  at  a  clear  under- 
standing   of   physiological   processes.       He   therefore   makes   his 


LEONARDO  AS  ANATOMIST  153 

anatomical  and  physiological  researches  conjointly,  cxpejiding  not 
infrequently  more  work  on  the  latter. 

Great  physicist  and  mathematician  as  Leonardo  is,  he  corrobo- 
rates his  physiological  investigations  by  experiments  and  by 
proofs  and  tests  drawn  from  physics  and  mathematics  ;  several 
of  his  dicta  emphasize  this  fact :  '  He  who  is  not  a  mathematician 
according  to  my  principles ',  he  says,  '  must  not  read  me ' ;  ^  and 
again,  '  Oh,  students,  study  mathematics,  and  do  not  build  without 
a  foundation  '."^  For  Leonardo  the  naturalist  it  was  a  matter  of 
course  to  seek  the  principles  of  movement  in  animals  in  the  laws 
of  mechanics. 

Under  the  heading  On  Machines  he  indicates  four  primary 
natural  forces  :  (1)  local  movement  which  is  produced  by  the 
three  other  forms  of  movement,  (2)  natural  weight,  (3)  force  and 
(4)  percussion. 

'  We  shall  therefore ',  he  says,  '  first  describe  this  local  motion 
and  how  it  produces  and  is  produced  by  each  of  the  three  other 
Powers.  Then  we  shall  describe  the  natural  weight,  although  no 
weight  can  be  termed  otherwise  than  accidental ;  but  so  it  has 
pleased  (us)  to  call  it,  to  distinguish  it  from  the  force  which  is, 
in  all  its  operations,  of  the  nature  of  weight  and  is  therefore  called 
accidental  weight ;  and  this  is  set  up  as  the  third  Power  of  Nature 
or  the  one  produced  by  Nature.  The  fourth  and  last  PoAver  shall 
be  called  percussion,  i.  e.  end  or  impediment  of  motion.  And  we 
shall  first  mention  that  every  local  involuntary  motion  is  produced 
by  the  voluntary  motor,  like  the  counterpoise  of  a  clock  lifted  up 
by  its  motor,  Man.'  ^ 

Thus  in  his  opinion  every  local  or  involuntary  movement  is, 
in  the  ultimate  analysis,  produced  by  a  motive  power  that  is 
itself  voluntary,  just  as  the  involuntary  movements  of  a  clock 
depend  ultimately  on  the  voluntary  movements  of  him  who 
raises  the  clock  weight. 

'Furthermore,  the  Elements  mutually  repel  or  attract  each 
other,  as  one  sees  that  water  expels  the  air  and  the  fire  entered  as 
heat  into  the  bottom  of  the  cauldrons  and  escapes  through  the 
bubbles  on  the  surface  of  the  boihng  water.  And  again  the  flame 
attracts  the  air,  and  the  heat  of  the  Sun  draws  up  the  water  in 
the  form  of  moist  vapour,  which  afterwards  falls  down  as  heavy 
rain  ;  but  percussion  is  the  immense  Power  of  things  which  is 
produced  in  the  Elements.'  ^ 

1  Q.  iv,  f.  14  V.  2  Q  j^  f  7  r.  3  Q  i^  fir,  4  q,  j^  f.  7  r. 


154  LKONAi:0()    AS    AXArOMlS'i' 

LuoJiaido's  general  idea  of  tiic  proper  nietlnxJ  for  the  inveati- 
<;alion  of  tlic:  Imin.in  Ixxly  and  its  parts  is  given  in  his  Plan  for 
the  Booh  : 

'  Tliis  liiy  I'xpositioji  (jf  the  liuniaji  form',  he  says,  '  sliaJi  be 
demonstrated  to  you  not  otlierwise  than  if  you  liad  the  real  man 
befoi(>  you  ;  and  the  reason  is,  tlial  if  you  want  to  know  tliorcju^hly 
the  parts  of  a  dissected  |)erson,  you  nmst  turn  him,  or  your  eye, 
examininjj;  liim  from  different  aspects,  from  below,  from  above, 
and  from  tiie  sides,  turning  liim,  and  inv<'stigating  tlie  origiji  of 
eaeii  member,  and  in  this  way  the  natural  dissection  has  satisfied 
you  as  to  your  knowledge.  J^ut  you  must  know  that  such  know- 
ledge does  not  satisfy  you  on  account  of  the  gieat  confusion  of 
])ainiicles  (membranes)  with  veins,  arteries,  nerves,  tendons, 
muscles,  bones,  and  blood,  which  colours  each  part  with  the  same 
colour,  and  the  vessels  which  empty  themselves  of  blood  are  not 
recognized  on  account  of  their  diminution  ;  and  the  integrity  of 
the  membranes  is  broken  b}^  the  examination  of  the  parts  which 
are  enclosed  in  them,  and  their  transparency,  tinged  by  blood, 
prevents  you  from  recognizing  the  parts  covered  by  them  on 
account  of  the  similarity  of  their  blood-colour  ;  and  you  cannot 
learn  to  know  these  ])arts  without  confounding  and  destroying 
the  others.  It  is  therefore  necessary  to  do  several  dissections.  .  .  , 
Thus  each  part  and  each  whole  will  become  known  to  you  by 
my  diagrams  with  the  aid  of  demonstrations  from  three  different 
aspects  of  each  part.  .  .  .  Accordingly,  the  cosmography  of  the 
microcosm  {minor  rnondo,  i.  e.  man)  will  be  demonstrated  to  you 
here  through  15  full  figures  in  the  same  order  as  has  already 
been  adopted  before  me  bj'^  Ptolemy  in  his  cosmography  of  the 
macrocosm  (i.  e.  the  world).'  ^  And  Leonardo  adds  :  '  You  must 
in  your  anatomy,  depict  each  phase  of  the  parts  from  man's 
conception  until  his  death  and  till  the  death  of  liis  bones,  stating 
which  ]3art  of  them  decays  first,  and  which  part  of  them  lasts 
longer.'  "^ 

Leonardo  was  a  well-read  man,  conversant  with  the  anatomical 
writings  of  Galen,  Avicenna,  Mondino,  and  Benedetti,  but  his 
opinion  of  authors  is  apparent  from  many  passages  in  his  works. 

'  I  do  not  understand  ',  he  says,  '  how  to  quote  as  they  do  from 
learned  authorities,  but  it  is  a  much  greater  and  more  estimable 
matter  to  rely  on  experience,  their  masters'  master.  These  men 
go  about  puffed  up,  and  boasting,  adorned,  not  with  their  own 
qualifications,  but  with  those  of  others,  though  they  will  not 
admit  mine.  They  scorn  me  who  am  a  discoverer  ;  yet  how 
much  more  do  they  deserve  censure  who  have  never  found  out 

1  Q.  i,  f.  2  r.  2  Q,  vi^  f,  22  r. 


LEONARDO  AS   ANATOMIST  155 

anything  but  only  recite  and  blazon  forth  other  people's  works.  .  .  . 
Those  who  only  study  old  authors  and  not  the  works  of  nature  are 
stepsons,  not  sons  of  Nature,  who  is  mother  of  all  good  authors.'  ^ 

The  depth  of  feeling  which  animates  Leonardo  during  his  work 
of  dissection  can  be  gauged  from  the  following  passage  : 

'  0  searcher  of  this  our  machine,  you  must  not  regret  that  you 
impart  knowledge  through  the  death  of  a  fellow  creature  ;  but 
rejoice  that  our  Creator  has  bound  the  understanding  to  so  perfect 
an  instrument.'  - 

And  what  demands  he  makes  on  the  dissector  are  seen  in  the 
following  : 

'  And  if  you  have  love  for  such  things  you  may  be  prevented 
by  nausea  ;  and  if  this  does  not  hinder  you,  you  may  be  prevented 
by  fear  of  living  during  the  night  hours  in  the  company  of  these 
quartered  and  flayed  corpses,  hideous  to  look  at ;  and  if  this 
does  not  deter  you,  perhaps  you  lack  the  good  art  of  draughtsman- 
ship, which  is  essential  for  such  demonstrations,  and  if  you  have 
the  art  of  drawing,  it  maj^  not  be  accompanied  by  the  sense  of 
perspective,  and  even  if  it  is,  you  may  lack  the  order  of  geometrical 
demonstrations,  and  the  method  for  calculating  the  force  and 
strength  of  the  muscles  ;  or  perhaps  you  lack  patience,  so  that 
you  will  not  be  painstaking.  .  .  . 

'  As  to  whether  all  these  things  have  been  in  me  or  no,  the 
hundred  and  twenty  books  written  by  me  will  furnish  sentence, 
yes  or  no,  for  in  these  I  have  not  been  hampered  by  avarice,  or  by 
negligence,  but  only  by  time.    Vale.'  ^ 

Leonardo's  nomenclature  is  very  deficient.  Bones,  muscles, 
nerves,  and  vessels,  have,  as  a  rule,  no  definite  names  but  are 
indicated  by  letters  or  some  such  means.  In  the  case  of  the  bones, 
the  old  names  that  were  in  use  by  mediaeval  writers  often  occur, 
for  example,  adiutorium  for  humerus,  furcula  for  clavicle,  focile 
maius  and  minus  for  the  ulna  and  radius  ;  the  muscles  are  also 
indicated  by  their  origins  and  insertions,  thus  'pars  domestica  and 
parssilvestris  describe  the  palmar  and  dorsal  sides  of  the  extremities, 
rascetta  and  pecten  manus  indicate  carpus  and  metacarpus  ;  and 
then  there  are  the  mediaeval  Arabic  terms  meri  for  oesophagus, 
sifac  for  jDeritoneum,  and  mirac  for  abdomen. 

Leonardo's  representation  of  embryological  conditions  is 
naturally  by  no  means  complete.    He  seems  to  have  examined  the 

^  Quoted  from  Oswald  Siren's  Leonardo  da  Vinci,  Stockholm,  1911. 
2  Q.  ii,  f.  5v.  3  Q   i^  f    i;}v. 


ir>(;  J.KONAIMX)   AS   ANATOMIST 

(•inlnyos  ot  ani mills,  liens,  and  calvoH,  befoiT  lie  studied  llie  human 
ioctus.  He  says  in  fact :  '  But  you  must  first  dissect  tlic  hatched 
vifil  I)(>tnn^  one  shows  the  difVerencM^  ])et\veen  th(^  Hver  in  the 
loetus,  and  the  lully  develojx'd  human.'  '  One  of  his  figures  ' 
is  evidently  taken  from  a  bird's  egg,  and  he  counsels  one  to 
observe  'how  the  bird  nourishes  itself  in  the  egg'.'*  He  remarks 
that  chickens  can  be  hatched  by  the  warmth  of  an  oven."* 

'  Ask  the  wife  of  Biagin  Crivelli  how  tlu^  capon  rears  and 
hatches  tlie  eggs  of  a  hen,  when  he  is  intoxicated.  Her  chickens 
are  given  into  the  care  of  a  capon,  wliich  is  plucked  on  the  under- 
side and  then  rubbed  with  nettles  and  set  under  a  basket ;  then 
the  chickens  go  in  under  it,  and  it  feels  it  is  being  tickled  by  the 
warmtli  and  likes  it,  for  which  reason  it  afterwards  leads  them 
and  fights  for  them,  jum])ing  into  the  air  against  the  goshawk  in 
ferocious  defence.'  ^ 

He  seems  also  to  have  sought  after  the  cause  of  difference  of 
sex,  and  considers  he  has  found  it  in  that  '  eggs  that  are  round- 
sha])ed  produce  males,  and  those  that  are  long-shaped  produce 
females  '.^ 

Leonardo  has  a  series  of  very  beautiful  drawings  of  the  human 
foetus  lying  in  the  uterus^  (Plate  xxvi).  The  position  of  the 
foetus  is  correct,  and  a]3parently  he  must  have  had  opportunity  to 
dissect  a  gravid  uterus,  but  much  of  his  work  must  have  been  done 
on  the  foetal  calf.  The  foetus  is  surrounded  by  three  membranes, 
the  '  animus ',  '  alantoydea ',  and  '  secondina ',  probably  correspond- 
ing to  the  amnion,  allantois,  and  chorion  of  our  notation.  He  does 
not  describe  a  placenta,  but  on  the  other  hand  his  drawings  show 
how  the  chorion  connected  in  several  places  with  the  inner  surface 
of  the  uterus  by  cotyledons,  the  male  cotyledons  on  the  chorion 
embracing  the  female  cotyledons  on  the  uterus. 

'  The  child  in  the  uterus  ',  he  says,  '  has  three  pannicuH  which 
surround  it,  of  which  the  first  is  called  Animus,  the  second  Alan- 
toydea, the  third  Secondina  ;  with  this  Secondina  (chorion)  the 
uterus  is  conjoined  by  means  of  the  cotyledons,  and  all  join  in  the 
umbilical  cord,  Avhich  is  composed  of  vessels.^  .  .  .  How  the  three 
panniculi  of  the  uterus  bind  themselves  together  by  means  of  the 
cotyledons  .  .  .  female  and  male  cotyledons.  .  .  .  Let  some  one 
give  you  the  secondina  of  a  calf  when  it  is  born,  and  observe  the 
form  of  the  cotyledons  whether  they  retain  the  male  or  female 

1  Q.  i,  f.  10  r.         ^  Q.  ill,  f.  8  v,  fig.  3.         ^  q   jji^  f   9  v.         4  q  jij^  f  7  j.. 
5  Ibid.  «  Ibid.  '  Q.  iii,  ff.  7  r.  and  8  r.  «  Q.  iii,  f.  8  v. 


I 


LEONARDO  AS  ANATOMIST  157 

cotyledons ;  I  observe  how  the  fetal  membranes  are  joined  to  the 
uterus,  and  how  they  loosen  themselves  from  it.'  ^ 

The  word  secondiiia  is  thus  used  by  him  in  various  senses  :  as 
chorion,  as  secundine,  and  as  foetal  membrane  generally. 

The  foetus  does  not  breathe  in  the  uterus,  for  it  would  drown 
if  it  did  so,  lying,  as  it  does,  in  water.^  Leonardo  considers  as  the 
reason  for  tliis  arrangement  that  heavy  things  weigh  less  in  water 
than  in  air,^  and  that  the  foetus  does  not  require  to  breathe  because 
it  is  animated  and  fed  by  the  mother's  life  and  nourishment.^ 
He  denies  the  truth  of  the  old  story  that  the  foetus  cries  or  wails 
in  the  uterus,  and  considers  that  any  sounds  that  seem  to  emanate 
from  a  gravid  uterus  must  be  caused  by  maternal  flatus.^  He 
frequently  remarks  that  '  one  soul  gov.erns  (the)  two  bodies  ',  and 
that  what  the  mother  eats,  and  the  impressions  she  receives,  leave 
their  mark  on  the  foetus.^  He  defines  the  length  of  the  full-grown 
foetus  as  a  braccio  and  the  length  of  an  adult  as  three  times  that 
of  the  full-grown  foetus.^  He  has  examined  a  foetus  which  was 
less  than  half  a  braccio  in  length  at  nearly  four  months.^  He 
remarks  '  how  in  four  months  the  child  is  half  of  its  length, 
i.  e.  eight  times  less  in  weight  than  when  it  is  born.'  ^  He  draws 
attention  to  the  fact  that  the  foetus  in  the  uterus  grows  three 
times  as  quickly  as  the  new-born  infant,  and  that  a  year  after 
birth  a  child  has  not  yet  attained  to  twice  the  length  of  a  nine- 
months-old  foetus.^"  He  has  examined  the  viscera  of  the  foetus, 
and  draws  attention  to  the  relatively  greater  size  of  the  left  lobe 
of  the  liver  at  this  stage  of  development,  and  points  out  that  it 
diminishes  after  birth."  He  seems  to  have  observed  the  conversion 
of  the  umbilical  vein  of  the  foetus  into  the  round  ligament  of  the 
liver  of  the  child.^^ 

As  a  result  of  his  study  of  conception  and  of  the  gro"\vth  and 
birth  of  the  foetus,  Leonardo  comes  to  the  conclusion  that  man 
and  his  works  are  in  no  way  things  isolated  in  nature,  but  are 
only  a  part  of  one  great  whole,  a  single  link  in  one  vast  chain, 
so  that  man  is  subject  to  the  same  '  necessita  '  as  all  other  living 
things.  He  formulates  these  thoughts  in  the  following  words  : 
'  Every  seed  has  an  umbilical  cord  which  breaks  when  the  seed  is 

1  Q.  iii,  f .  8  r.                ~  Q.  iii,  f .  7  r.            ^  Q.  iii,  f.  1  v.  *  Q.  in,  f .  8  v. 

5  Q.  iii,  f .  7  V.                 «  Q.  iii,  ff.  3  v.  and  8  v.  '  Q.  iii,  f-  7  r. 

«Q.  iii,  f.  7v.                9Q.  i,  f.  lOr.  lo  Q.  iii,  f.  7  v. 
"  Q.  iii,  f.  8  V  and  Q.  i,  f.  10  r.                         12  q.  iji^  f.  jq  v. 


158  LRONAIIDO   AS   ANATOMIST 

niatuic.  And  similarly  they  have  matrix  and  secondina  as  tlie 
herbs  and  all  the  seeds  whieh  grow  in  pods  show.'  ^  In  this  con- 
nexion we  meet  one  of  lA'onardo's  characteristically  abrupt 
transitions  of  thought.  While  sketching  a  fot^tus  in  the  intra- 
uterine position  with  elbow  bent  and  hand  prone,  he  suddenly 
asks  himself  which  muscles  flex  the  elbow-joint,  and,  immediately 
under  tlie  drawing  of  the  foetus,  makes  two  rough  sketches  of  the 
muscles  of  the  arm  with  pronated  hand  and  the  following  legend 
attached.  '  Demonstrate  here  only  those  muscles  which  serve  to 
bend  the  arm  to  a  right  angle  and  those  which  cause  it  to  turn  the 
hand  back  and  forward.  Do  not  concern  yourself  with  anything 
else,  but  demonstrate  only  the  functions  performed  by  those  muscles 
which  rise  immediately  from  the  bone  of  the  said  humerus.'  " 

Leonardo  differs  from  many  of  the  mediaeval  wTiters  who 
preceded  him  in  representing  the  uterus  with  only  one  cavity. 
The  tubes  go  outwards  and  upwards  and  the  ovaries  lie  to  the 
side  of  the  uterus.  On  the  right  the  artery  of  the  ovary  is  seen  to 
come  from  the  aorta  and  the  vein  to  go  to  the  vena  cava  inferior 
(Plate  xxvii).  The  ovaries  are  designated  as  'seed-vessels  [vasi 
spermatici)  in  the  form  of  testicles,  and  her  seed  is  first  blood  like 
that  of  the  male  '.^  He  is  aware  too  that  there  is  a  difference 
between  the  male  and  the  female  pelvis.  '  Measure  how  much  less 
the  woman's  pubic  bone  is  than  the  man's.  It  is  for  the  sake  of 
the  space  between  the  lowest  part  of  the  pubic  bone  and  the 
point  of  the  coccyx  in  ^dew  of  parturition.'  ■* 

It  is  apparent  from  various  drawings  that  Leonardo  had 
a  fairly  good  knowledge  of  the  structure  and  relations  of  the 
testis,  vas  deferens,  vesiculae  seminales,  vasa  spermatica  and 
nervi  spermatid  interni  (Plate  xxvii),  '  nerves,  originating  in  the 
vertebral  column,  which  join  the  vein  of  the  testicle  ',^  although 
here  also  he  partly  transfers  his  findings  from  animals  to  man. 

Leonardo  discusses  the  results  of  conception  from  the  union 
of  white  and  black  parents,  and  remarks  that  the  colour  of  the 
offspring  is  not  conditional  upon  the  influence  of  the  sun  but  of 
the  parents'  colour,  and  states  '  that  the  mother's  seed  has  an 
influence  on  the  embryo  equal  to  that  of  the  father  '.^ 

A  number  of  general  observations  on  Osteology  are  found  in 

1   Q.  ui,  f.  9  V.  2   Q    iii^  f    7  V.  3   Q    iii    f    1  V. 

«  Q.  iii,  f.  4  V.  5  Q  iii^  f.  3  r.  e  q  jjj^  f  §  ^- 


PLAT  K    X  X  \'  I  I 


3    :^.^JUoUp*^^ 


Ouadcrni    I  I  I   to.   i  v 


(Left)  General  structure  of  uterus  and  sources 

of  its  blood  suppl}'. 
(Right)  Male  organs. 


Z^- 


Ouadcrni  V  t"o .   i  8  r 

Topographical  anatomy  of  neck  and  shoulder  in 
a  thin  aged  individual. 


LEONARDO  AS  ANATOMIST  159 

the  Quaderiii,  whicli  could  only  have  been  written  by  one  well 
versed  in  the  subject.    In  the  Plan  for  the  Book  occurs  this  passage  : 

'  It  is  necessary  to  make  three  dissections  for  the  anatomy 
of  the  bones,  which  must  be  sawn  through  to  demonstrate  which 
is  perforated  and  which  is  not,  which  is  medullary  and  which  is 
spongy,  and  whic*h  from  without  inwards  is  thick  and  which  is 
thin,  and  whicli  at  one  place  has  great  thinness,  and  at  one  place 
is  thick  and  at  one  is  perforated  or  full  of  bone,  or  medullary  or 
spongy,  and  thus  all  these  things  will  sometimes  be  found  in  the 
same  bone,  and  there  may  be  a  bone  which  has  none  of  them.'  ^ 

In  another  place,  Leonardo  writes  :  '  Bone  is  of  inflexible 
hardness  adapted  for  resistance,  and  is  without  feeling.  It 
terminates  in  cartilages  at  its  extremities.  And  the  medulla  is 
composed  of  sponge,  blood  and  soft  fat  covered  with  the  finest 
veil.    Spongy  bone  is  a  substance  composed  of  bone,  fat  and  blood.'  ^ 

Leonardo's  treatment  of  the  hands  in  his  paintings  is  well 
known.  Under  the  heading  The  Hand  from  the  Inside  he  demands 
that  the  bones  shall  first  be  studied  in  order,  so  that  their  number, 
shape,  and  position  should  be  learnt,  and  afterwards  they  should 
be  further  examined  by  being  sawn  through  ;  they  must  then  be 
put  together  according  to  the  articulations  ;  then  the  muscles 
that  connect  carpus  with  metacarpus  and  the  tendons  which  move 
the  first,  second,  and  third  joints  must  be  demonstrated  ;  next 
the  nerves,  arteries  and  veins,  then  the  hand  as  a  whole  with  the 
skin  must  be  examined,  and  lastly  the  measurement  of  the  hand 
and  its  parts  must  be  given.  A  similar  systematic  procedure  must 
be  adopted  in  dealing  with  the  back  of  the  hand.^ 

With  the  exception  of  two  delicate  sketches  in  red  chalk  of 
the  bones  of  the  lower  limbs  set  at  the  correct  incHnation  to  the 
pelvis  (Plate  xxxv),  the  Quaderni — in  contrast  with  the  Fogli — 
contain  no  osteological  drawings  of  great  interest,  but  only 
a  few  rough  sketches,  mostly  of  the  bones  of  the  extremities. 
A  drawing  of  the  cranium,  the  cervical,  and  part  of  the  thoracic 
vertebrae  has  no  close  relation  to  the  actual  facts. ^  This  drawing 
must  date  from  the  earliest  period  of  Leonardo's  anatomical 
studies,  before  he  had  begun  to  dissect,  and  when  his  fantasy  had 
free  reign,  working  rather  on  information  gained  from  books, 
and  possibly  from  old  drawings  that  have  now  disappeared  than 
on  actual  observation. 

1  Q.  i,  f.  2  r.  2  Q  ii  £   18  V.  3  Q  i^  f  2  r.  *  Q.  ii,  f.  5  v. 


160  l.KOXAKDO   AS   ANATOMIST 

As  regards  tlic  morpliology  of  the  muscloH,  Looiiardo  writes  : 

*  Muscles  are  of  many  kinds,  some  without  tendons,  like  the 
trahcculae  in  the  right  vejitri(;le  of  the  heart,  and  otheis  simihir. 
Sonic  a.re  round  hke  tiie  abovci-rnentioned  and  isohited  {ina.sculi 
papiUdrcf^),  being  coiniected  only  by  tendons  {chordap,  tendineae) 
witii  tiiat  of  tlie  flexible  part.  .  .  .  Some  are  broad  and  tliin,  some 
broad  and  tliiek,  some  long  and  nairow,  others  long  and  tiiiek  ; 
some  arc  thin  and  oval,  some  shaped  like  a  fish,  others  like  a 
lizard,  some  are  twisted  and  some  straight.  Some  have  tendons 
along  one  side  only,  others  at  both  (mkIs,  others  are  divided  by 
several  tendons,  as  for  instance  the  longitudinal  muscles.  Some 
may  move  the  ])art  from  either  end,  others  from  one  end  only, 
another  moves  behind  its  tendon,  others  draw  their  tendons 
towards  themselves.'  * 

Leonardo  states  that  muscles  move  longitudinally,'  and  he 
speaks  generally  of  muscles  wntli  several  heads. ^  in  a  passage  on 
Definition  of  the  Instruments  he  writes  :  '  The  nuiscles,  the  func- 
tionaries of  the  nerves,  draw  to  themselves  the  tendons  which 
are  connected  to  these  members.  .  .  .  The  tendons  are  mechanical 
instruments  which  in  themselves  have  no  feeling,  but  carry  out 
whatever  is  imposed  upon  them.'  "* 

In  order  to  demonstrate  the  structure  of  the  lower  limb  and 
the  actions  of  its  muscles  he  gives  three  illustrations  of  models 
formed  from  copper  Avire  (Plate  xxviii).  These  are  in  the  main 
correct  and  to  them  Leonardo  attaches  the  following  text : 

'  How  many  muscles  originating  in  the  hip  are  formed  for  the 
movement  of  the  femur  ?  Present  the  leg  in  full  relief  and  make 
the  cords  of  red-hot  copper  ware,  and  bend  them  on  it  to  their 
natural  position,  and  when  you  have  done  this  you  will  be  able 
to  sketch  them  from  foux  sides,  and  place  them  as  they  are  in 
nature,  and  discuss  their  functions.  When  you  have  finished 
with  the  bones  of  the  lower  Umb,  give  the  number  of  all  the  bones, 
and  having  completed  the  tendons,  give  the  number  of  these 
tendons,  and  you  must  do  the  same  with  the  muscles  and  the 
nerves,  the  veins  and  the  arteries,  stating :  the  thigh  has  so  many, 
the  leg  so  many,  the  foot  so  many,  and  the  toes  so  many,  and 
then  you  must  say  :  so  many  muscles  spring  from  a  bone  and 
end  in  a  bone,  and  there  are  many  that  spring  from  a  bone  and 
end  in  another  muscle,  and  in  this  manner  you  can  describe  each 
detail  of  every  part  of  the  body,  and  especially  the  ramifications 
made  by  some  muscles  which  produce  various  tendons.'  ^ 

1  Q.  ii,  f.  15  r.  ^  q  j^^  f ,  g  j.  3  q  jji^  f  9  v. 

4  Q.  ii,  f.  18  V.  5  Q   V  f.  4r. 


I^  L  A  T  !•:     X  X  \'  1  I  1 


'•"»'.„(/i.'(      1411  .li-^v.   «<,(,'!     ...rf 


.  I       . 


f5  vrtv*]  rt«»tw 

_ A-   OfW- 


C.V^ 


r'  « 


irj) 


i*n^. 


»..'., V 


Ouadenii   \'  fo.  4  r 

Bones  of  lower  limb  to  which  wires  arc  fitted  to  illustrate 
lines  of  nuisinilar  traction 


LEONARDO  AS  ANATOMIST  161 

Leonardo  emphasizes  the  fact  that  with  the  knee  flexed  the 
action  of  tlie  sartorius  muscle  gives  rise  to  internal  rotation  and 
the  biceps  to  external  rotation,  but  when  on  the  other  hand  the 
knee  is  extended,  rotation  of  the  limb  can  only  occur  at  the  hip- 
joint.    He  adds  : 

'  Nature  has  attached  all  the  muscles  which  control  the  move- 
ments of  the  toes  to  the  bones  of  the  leg  and  not  to  the  thigh, 
because  these  muscles,  when  the  knee  is  bent,  would,  if  they  were 
attached  to  the  thigh-bone,  contract  and  become  locked  under 
the  knee-joint,  and  would  not  be  able  without  great  difficulty  and 
effort  to  work  the  toes.'  ^ 

The  biceps  hracJiii  is  described  as  a  flexor  and  supinator,  the 
brachialis  anticus  as  a  powerful  flexor  only,  the  pronator  radii  teres 
as  pronator  and  antagonist  of  the  biceps.-  All  these  are  compared 
with  the  cords  of  the  '  trepan '  which  serve  to  pronate  and 
supinate  the  hand.  The  ulna  is  characterized  as  'non-rotating' 
in  contradistinction  to  the  radius,  and  it  is  sj)ecified  that  pronation 
and  supination  take  place  '  without  alteration  of  the  bone  which 
is  called  adjutorium  (humerus)  \^  It  is  stated  that  when  the 
arm  is  bent  at  the  elbow  the  flexor  muscles  contract  whilst  the 
extensors  stretch  as  the  angle  of  the  bend  becomes  more  acute.* 
The  three  parts  of  the  deltoid  muscle  and  their  functions,  together 
with  those  of  the  pectoralis  major  and  teres  inajor,  are  correctlj^ 
reproduced.^ 

The  muscles  of  the  back  are  stronger  than  those  of  the  front, 
for,  since  one  can  bend  farther  forward  than  backward,  more  power 
is  required  to  raise  oneself  after  bending  forward  than  backw^ard.^ 

The  topographical  dissections  carried  out  by  Leonardo,  of  the 
throat  and  adjacent  parts,  are  significant.'  Of  these  he  has  made 
a  series  of  drawings  ranging  from  rough  sketches  to  illustrations 
which  reproduce  carefully  performed  dissections  in  great  detail. 
With  these  may  be  classed  a  pair  of  dehcate  silver-points  where, 
through  the  thin  skin  of  aged  subjects,  we  discern  the  fossae  of  the 
throat  with  the  underlying  muscles  (Plate  xxvii).  In  another 
drawing  Leonardo  has  topographically  reproduced  the  lower 
section  of  the  face,  the  column  of  the  neck,  the  hyoid  bone  and  its 
connexion  to  the  styloid  process,  the  larynx,  trachea,  sterno-cleido- 
mastoid,  trapezius,  splenins,  scaleni,   levator  anguli  scapulae,   the 

1  Q.  vi,  f.  17  r.  2  Q   iii  f  9  V  3  Q   iv,  f.  U  r.  *  Q.  vi.  f.  20  r. 

5  Q.  vi,  f.  13  r.  6  Q   iv',  f.  G  r.  '  Q.  v,  ff.  15-lS,  and  20. 


162 


LEOXAKBO   AS   ANATOMIST 


jujjjular  vein  witli  its  liibutaries,  the  carotid  artei*y,  the  rof/n^s 
with  th«'  superior  hirymipftl  and  the  hypoghfisal  nerveK  and  what 
seems  to  he  the  snb-maxillary  gland,  though  it  is  perhay)8  a 
lymph  node  (Plate  \.\\).  It  is  remarkable  that  in  these  regional 
draAvings  of  the  human  throat  he  should  havc^  taken  his  model  for 
the  hyoid  bone  and  larynx  not  from  a  human  subject  but  from 

an  animal,  perhaps  a  dog. 
His  serial  sections  of  the 
lower  extremities  are  also 
noteworthy.  Leonardo 
seems  to  have  been  the  first 
to  make  topographical  dis- 
sections and  serial  sections 
to  illustrate  the  structure 
of  the  parts  (Fig.  1). 

Leonardo's  papers  on 
comparative  anatomy  also 
display  his  great  skill  as  a 
dissector,  and  his  under- 
standing of  anatomical 
conditions.  As  comment- 
ary to  a  finished  drawing 
of  the  abdomen  and  lower 
limbs  of  a  muscular  man, 
he  Avrites  : 

'  In  order  to  make  the 
comparison  you  must  draAV 
the  leg  of  a  frog  which  has 
great  resemblance  to  that 
of  a  man  in  the  bones  as  in  the  muscles.  This  must  be  followed 
by  the  hare's  hind  leg,  which  is  very  muscular,  with  conspicuous 
muscles  unimpeded  by  fat.'  ^ 

On  a  folio  of  red-brown  paper,  between  exquisite  drawings  of 
muscular  men  and  of  the  skeleton  of  the  pelvis  and  the  lower 
limbs  of  a  man  and  a  horse,  in  which  some  muscles  are  marked 
out  by  cords  (Plate  xxxv),  Leonardo  thus  Avrites  : 

'  The  union  of  the  fleshy  muscles  with  the  bones  without  any 
tendon  or  cartilage — and  you  must  do  the  same  with  several 
animals  and  birds.    Represent  the  man  on  tiptoe  so  that  you  can 

1  Q.  V,  f .  23  r. 


Fig.  1.     Leonardo's  use  of  serial  sections 


LEONARDO  AS  ANATO:\IIST  1()3 

more  easily  compare  him  with  other  animals.  Draw  the  man's 
knee  bent  like  the  horse's.  In  order  to  compare  the  skeleton  of 
a  horse  with  that  of  a  man,  you  must  present  the  man  on  tiptoe, 
when  portraying  the  bones.  On  the  affinity,  which  the  conformity 
of  bones  and  muscles  of  animals  have  with  the  bones  and  muscles 
of  man.'  * 

Leonardo's  great  dissecting  skill  is  seen  again  in  the  most 
perfect  way  in  certain  figures  which  display  the  muscles  and 
tendons  on  the  distal  portion  of  the  leg  and  on  the  foot,  together 
with  a  part  of  the  crucial  ligament  as  well  as  the  vaginal  sheaths 
of  the  tendons.  In  these  figures  the  toes  are  armed  with  claws  of 
some  cat-like  animal,  perhaps  a  lion^  (Plate  xxx).  These  drawings 
are  by  no  means  faultless  in  details,  since  the  inner  and  outer 
edges  of  the  foot  have  been  interchanged,  but  they  show,  by  the 
combination  of  the  foot  of  a  man  with  an  animal's  claws,  one  of 
Leonardo's  most  outstanding  traits,  his  highly  imaginative  and 
artistic  creative  spirit.  The  treatment  of  these  sketches  with 
silver-point  and  colour,  united  to  the  author's  power  as  a  dissector 
and  artist,  give  them  a  peculiar  charm.  They  are  without  text, 
and  Leonardo  must  have  felt  that  they  conveyed  a  sufficiently 
obvious  and  clear  meaning. 

The  study  of  the  diaphragm  is  a  subject  which  Leonardo  pursues 
with  especial  predilection. 

'  It  is  shaped ',  he  says,  '  like  a  deeply  hollowed  spoon.^  ...  If 
it  were  not  arched  so  that  it  could  receive  the  stomach  and  other 
viscera  into  its  concavity  it  could  not  afterwards  contract  .  .  . 
and  exert  pressure  on  the  intestines,  and  drive  the  food  from  the 
stomach  into  the  intestines,  nor  could  it  help  the  abdominal  muscles 
to  expel  the  faeces,  nor  could  it  by  contracting  enlarge  the  thoracic 
cavity  and  compel  the  lung  to  expand,  so  that  they  may  inspire 
air  to  refresh  the  veins  coming  from  the  heart.'  * 

Leonardo  points  out  that  the  diaphragm  has  four  functions, 
primarily  it  is  a  respiratory  muscle,  secondly  it  presses  on  the 
stomach  and  drives  its  contents  into  the  intestine,  thirdly  it  aids 
the  abdominal  wall  in  the  act  of  defaecation,  and  fourthly  it 
divides  the  '  spiritual  parts '  (the  lungs  and  heart)  from  the  '  natural 
parts '  (the  abdominal  organs).^  All  these  functions  are  brought 
into  action  by  the  rise  and  fall  of  the  diaphragm.  The  way  in 
which  the  movements  of  the  diaphragm  and  the  abdominal  wall 
1  Q.  V,  f.  22  r.  2  Q.  v^  f},  ii_i4,  3  q  j^  f,  5  j. 

*  Q.  i,  f.  4  V.  5  Q.  i,  f.  o  r.  and  v. 


1(>4  LK()XAI{|)()    AS    AXATOiVllST 

ttltiTiiatc,  lii'vc  ('l>l»  and  How,  is  dcwcribed  and  illustrated  by  an 
outline  drawing.'  Leonardo  .states  tliat  the  muscles  outside  the 
ribs  {serrati)  must  regulate  them  when  the  dia[)hragm  contracts, 
as  it  would  otherwise^  draw  down  the  ribs,  it  being  attached,  to 
them  at  its  margin.- 

Lconardo's  treatment  of  the  cerebral  ventricles  clearly  shows 
the  development  of  hif^  investigations  fiojn  vague  and  groping 
efforts,  based  on  ancient  and  erroneous  views  (Plate  xxix,  upper 
figure)  to  his  own  independent  study  of  the  phenomena  (Plate 
XXIX,  lower  figure).  By  means  of  sagittal  and  horizontal  sections 
through  the  head,  he  sketches  the  cerebral  ventricles  as  three  small 
vesicles  lying  behind  each  other  and  nearly  equal  in  size,  the 
foremost  of  which  is,  by  means  of  canals  (i.  e.  nerves),  connected 
with  the  eye  and  ear.''  In  all  this  he  has  simply  followed  earlier 
authors.  On  the  same  sheet  is  drawn  a  cross-section  of  an  onion. 
After  he  has  calculated  the  layers  he  successively  cuts  through  in 
bisecting  the  head,  he  says : 

'  If  you  cut  an  onion  through  the  middle  you  will  be  able  to 
observe  and  count  all  the  circular  layers  and  cases  which  cover 
the  centre  of  the  onion.  In  the  same  way,  if  you  wish  to  bisect 
a  human  head,  you  will  first  cut  through  the  hair,  then  the  skin, 
then  the  muscular  flesh  and  the  peri-cranium,  then  the  skull,  and 
inside  that  the  dura  mater  and  pia  mater,  and  the  brain,  thereupon 
(i.  e.  at  the  base)  again  the  pia  and  dura  mater,  and  rete  mirabile 
and  the  base,  the  bone.' 

But  on  another  f oho  he  approaches  much  nearer  the  actual  con- 
ditions and  illustrates  almost  perfectly  by  horizontal  sections  and 
profile  drawings  the  inner  aspect  of  the  base  of  the  skull,  the  base  of 
the  brain,  the  surface  of  the  cerebral  hemispheres,  and  the  cerebral 
ventricles  and  their  relations  to  each  other.'*  He  enumerates  three 
ventricles  and  the  drawings  show  that  he  counts  both  the  lateral 
ventricles,  which  are  connected,  as  one  (Plate  xxix).  He  designates 
the  lateral  ventricles  as  impressiva,  the  third  cerebral  ventricle  as 
sensus  coynmunis,  and  the  fourth  as  memoria ;  this  last  seems  to 
continue  downwards  into  the  spinal  cord  as  a  thin  tube  ( ?  the 
central  canal).  The  fourth  cerebral  ventricle  is  mentioned  as  the 
source  or  meeting-point  of  '  all  nerves  wliich  give  feeling '. 

In  order  to  acquire  a  correct  idea  of  the  ventricles,  Leonardo 
performed  the  following  experiment.  Into  a  brain  removed  from 
the  cranium,  he  injected  melted  wax  through  a  hole  in  the  fourth 

1  Q.  i,  f.  G  V.  ~  Q.  iv.  f.  1  r.  ^  Q.  v,  f.  6  v.  *  Q.  v,  f.  7  r. 


4,K3r.^^jt,., 


v:r' 


fAr^V-  .  Q 


Quaderni  V  fo.  6  x- 
Ventricles  and  layers  of  head  and  eye  in  section 


^1, 


Quaderni  V  fo.  7  r 


LEONARDO  AS  ANATOMIST  165 

ventricle,  having  already  made  an  opening  in  both  the  lateral 
ventricles  and  inserted  a  tube  so  that  '  the  air  can  stream  out '. 
He  then  removed  the  brain  matter  from  the  wax  so  as  to  display 
the  shape  of  the  casts  formed  in  the  ventricles.  He  made  a  similar 
experiment  with  a  brain  without  removing  it  from  the  cranium, 
injecting  the  wax  through  a  hole  bored  through  the  base  of  the 
skull,  which  probably  led  up  through  the  infundibulum.  His 
words  are — 

'  Make  two  air-holes  in  the  horn  of  the  larger  ventricle  and 
inject  the  melted  wax  into  it,  at  the  same  time  making  a  hole 
in  the  memoria  and  fill  through  such  a  hole  the  three  ventricles 
of  the  brain  ;  and  then  when  the  wax  has  hardened,  remove  the 
brain  and  you  will  see  the  exact  form  of  the  three  ventricles.  But 
first  insert  the  fine  tubes  into  the  air-holes,  so  that  the  air  in  the 
ventricles  can  stream  out,  giving  place  to  the  injected  wax.  The 
shape  of  the  sensus  communis  filled  with  wax  through  the  hole  M 
at  the  bottom  of  the  basis  cranii,  before  the  cranium  was  sawn 
through  '  (Plate  xxix). 

These  operations  of  filling  the  soft  brain  cavity  with  a  solidi- 
fying substance  are  fraught  with  many  difficulties,  and  it  is  not 
an  easy  matter  to  get  casts  true  to  nature.  As  is  to  be  expected, 
therefore,  the  figures  show  certain  deviations  from  the  actual 
state  of  the  parts.  He  was,  however,  the  first  to  conceive  the 
idea  of  injecting  a  solidifying  substance  into  the  cerebral  cavities, 
and  he  was  the  first  to  give  a  fairly  correct  representation  of 
those  cavities.  Yet  as  recently  as  the  twentieth  century  the 
claim  of  priority  in  this  method  has  been  made^  for  a  modern  in- 
vestigator, though  it  was  in  use  nearly  four  hundred  years  before 
his  time.^ 

On  several  pages  in  the  Quaderni  are  drawings  of  a  number  of 
cerebral  nerves  and  of  the  spinal  cord.^  In  one  such  drawing 
of  the  base  of  the  brain  we  see  the  olfactory  nerves,  and  behind 
them  the  optic  tract  with  chiasma  and  optic  nerve  and  bulbs, 
behind  these  again  are  shown  branches  to  the  superior  maxilla 
from  the  trigeminal,  next  the  vagi,  and  farthest  back  the  spinal 
cord.  Elsewhere  the  vagi  are  sketched  in  their  length,  and  shown 
passing  from  the  thorax  into  the  abdomen,  where  they  obviously 

^  Cf.  Regius  on  the  Raube-Welche  drawings,  Biologische  Unlersuchungen,  1911. 

2  Cf .  Holl,  '  Leonardo  da  Vinci ',  in  the  Archiv  fiir  Anatomie  und  Physiologie, 
1911. 

3  e.  g.  Q.  V,  f.  8  r. 


2391 


M 


lOfJ  LKUNAllDO   AS  ANATOMIST 

ramify.'  On  other  |)aj>;rs  aro  smi  the  liypofflossal,  aiul  tlic  va<i;iis, 
with  the  superior  hiryiij^eal.-  Leonardo  often  mentions  tlio 
inferior  hiryngeal,  7iervi  reversiviy  a.s  he  calls  tliem.  '  The  recurrent 
ner\ cs  are  l)ent  upwards  only  because  they  would  he  lorn  asunder 
in  the  threat  movement  wliieli  tlu^  neck  makes  in  extending  itself 
forward  and  further  because  it  |)artly  carries  witli  it  tiie  trachea 
and  such  nerves.'*' 

In  one  outline  drawing  Leonardo  |)rol)ably  intended  to  repre- 
sent the  medulla  oblongata/  To  this  sketch,  indistinct  and 
obscure,  are  attached  some  passages  which  show  tliat  he  had 
grasped  the  importance  of  the  spinal  cord  by  experiments  on 
frogs.  '  The  frog  retains  life  for  some  hours  after  the  head,  heart, 
and  intestines  are  removed.  And  if  you  perforate  this  cord,  it 
immediately  shrivels  and  dies.  All  the  nerves  of  the  animals 
derive  from  here.  And  if  you  perforate  the  said  string  it  suddenly 
twitches  and  dies.'  And  on  the  back  of  the  sheet  the  description 
of  these  experimental  investigations  continues  thus  :  '  The  frog 
instantly  dies  when  its  spinal  cord  is  perforated.  And  formerly 
it  lived  without  head,  without  a  heart,  or  any  entrails  or  intestine 
or  skin.  It  thus  seems  that  here  lies  the  fundamentum  of  motion 
and  of  life.'  Similar  outline  drawings  are  found  in  others  of 
Leonardo's  manuscripts.'^ 

Both  in  the  Fogli  and  the  Quaderni,  a  cord-like  structure  is 
seen  on  either  side  of  the  spinal  cord  stretching  down  from  the 
brain  to  the  foramina  in  the  transverse  processes  of  the  vertebrae. 
There  are  several  connexions  shown  between  these  cord-like 
structures  and  the  spinal  cord,  and  they  are  also  connected  with 
the  brachial  plexus.  These  structures  are  products  of  his  imagina- 
tion :  they  cannot  be  the  vertebral  arteries.  It  may  be  that  an 
explanation  of  them  would  result  from  a  further  investigation  of 
his  sources.^ 

In  the  Fogli  much  of  the  peripheral  nervous  system  is  correctly 
reproduced,  but  in  the  Quaderni  it  is  on  the  whole  cursorily 
treated.  The  brachial  plexus  can  be  traced  sometimes  to  the 
elbow,  sometimes  to  the  wrist  and  hand.'  The  lumbar  plexus  is 
seen  to  consist  of  three  lumbar  nerves  from  which  issue  the  femoral 

1  Q.  i,  f.  13  V.  -  Q.  V,  ff.  16  r.  and  17  r.  ^  q   j   f   13  v. 

4  Q.  V,  f.  21  r,  fig.  5.  5  e.  g.  Fogli  B,  f .  4  r.  and  v.  and  f .  23. 

^  Cf.  Holl,  '  Leonardo  da  Vinci ;    Quaderni  d'Anatomia ',  v  and  vi,  Archiv 
f.  Anatomie  und  Physiologie,  1917. 
'  Q.  V,  ff.  19r.,  21r.  and  v. 


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Q 

LEONARDO  AS  ANATOMIST  167 

nerve  Avith  a  branch  to  the  inside  of  the  leg  besides  a  number  of 
other  branches,^  and  the  sacral  plexus  is  represented  with  branches 
of  the  ischiadic  nerve  distributed  to  the  pelvis,^  high  up  on  the 
thigh  ^  and  above  the  knee.  * 

Leonardo  devotes  a  large  portion  of  his  researches  to  the 
consideration  of  the  lungs  and  respiration.  His  portrayal  of  the 
lungs  seem  to  be  based  on  examination  of  animals  ^  as  well  as  of 
man.''  He  knows  the  shape  of  the  lungs  and  their  lobes.'  Their 
substance  is  dilatable,  extensible  and  spongy,  and  they  are  enclosed 
in  a  delicate  membrane  (the  pleura)  which  interposes  itself  into 
the  spaces  between  the  ribs  when  they  expand.®  He  shows  how 
the  pleura  covers  the  inner  side  of  the  ribs  and  the  surface  of  the 
diaphragm  ^  and  he  discusses  if  there  be  air  in  the  pleura.  '  Whether 
between  the  lungs  and  the  chest,  at  any  part,  a  quantity  of  air 
interposes  itself  or  not.'  ^°  Later  he  decides  against  this  view 
'  because  there  can  be  no  vacuum  in  nature,  the  lung,  which 
touches  the  ribs  on  the  inside,  must  follow  their  dilatation  '. " 

The  bronchi  ramify  in  the  lung  substance,  and  gradually 
diminish  until  they  become  blind  tubes  which  develop  minute 
vesicles  when  inflated.  These  endings  are  drawn  and  described, 
both  inflated  and  empty,  '  trachea  minima  uninflated  and  again 
inflated  which  redoubles  its  capacity  in  its  increasing  ',^^  and 
throughout  the  lungs  the  bronchi  are  accompanied  by  the  blood- 
vessels and  the  finest  ramifications  of  the  bronchi  are  in  close  touch 
with  the  most  minute  branches  of  the  blood-vessels.^"^  Whilst  in 
many  of  Leonardo's  drawings  the  two  bronchi  enter  the  lung 
near  its  apex,  others  show  approximately  the  actual  conditions 
(Plate  xxxvi),  and  here  he  says,  '  first  describe  the  entire 
ramification  of  the  trachea  in  the  lung,  and  then  the  ramifica- 
tions of  the  veins  and  arteries  each  separately,  and  tlien  all  three 
together  '.^* 

On  the  findings  of  his  experiments  with  inflation  of  the  lungs, 
Leonardo  considers  it  impossible  that  air,  as  such,  can  reach  the 
heart  from  the  bronchi  ;  on  the  contrary  he  holds  that  it  is  the 
pulmonary  arteries  that  receive  '  the  freshness  of  the  air  '  from  the 
bronchi.     '  To  me  it  seems  impossible  that  any  air  can  penetrate 

1  Q.  V,  ff.  9  r.,  20  v.,  and  21  r.                 2  q  j^^  f  9  r.              3  q.  y,  f.  9  v. 

*  Q.  V,  f.  15  r.                       5  e.g.  Q.  ii,  f.  1  r.  «  e.g.  Q.  ii,  f.  7  v. 

'  Q.  iii,  f.  4  V,  fig.  7.            s  q   j}^  f   i  j..  9  Q.  iv,  f.  3  r. 

i«  Q.  ii,  f.  7  V.                    "  F.  A,  f.  15  v.  ^2  q  \\^  f.  i  r.  and  f.  2  r. 
13  Q.  ii,  f.  Ir.                     i«  Q.  iii,  f.  10  v. 

M  2 


16S 


LKOXAKDO    AS   AXATOMIS'I^ 


into  the  licait  througli  the  t)iach(.'a  (i.  e.  tlic  hronclii)  for  he  who 
iiitlatcs  llu'sc  (Iocs  Jiot  expel  any  air  froni  any  |)art  of  these,  and 
this  oeeurs  beeause  of  the  dense  pannieulo,  vvitii  wliieli  the  whole 
ramification  of  the  trachea  is  coated,  which  ramification  goes 
on  dividing  into  the  minutest  branches  together  with  the  minutest 
branches  of  the  veins.''  And  '  the  lung  is  unable  to  transmit  air 
to  the  heart  .  .  .  and  further  the  air  which  is  inhaled  by  the  lung 
continually  enters  dry  and  cooi,  and  leaves  Aioist  and  iiot.  But 
the  arteries  which  join  themselves  in  continuous  contact  with  the 
ramification  of  tjie  trachea  distributed  through  the  lung  are  those 
which  take  up  the  freshness  of  the  air  which  enters  such  lung.' 
Leonardo  thus  represents  the  bronchi  as  a  tubular  system, 
terminating  blindly,  from  the  expanded  ends  of  which  the  inhaled 
air  passes  to  the  pulmonary  blood-vessels.  '  The  dilatation  of  the 
lungs  occurs  in  order  that  the  lungs  may  inhale  the  air  with  which 
the  veins  which  the  heart  sends  into  them  can  refresh  themselves.'  * 

Leonardo  frequently  afiftrms  that  the  diaphragm  is  the  most 
essential  respiratory  muscle  ;  but  in  deep  inhalations  such  as 
a  yawn  or  sigh,  the  contraction  of  the  diaphragm  is  insufficient  ; 
then  the  serratus  posticus  superior  comes  into  action.  This  he 
describes  as  made  up  of  six  muscles,  three  on  either  side,  which 
stretch  from  the  vertebral  column  to  the  uppermost  ribs.  The 
mode  of  action  of  these  muscles  is  demonstrated  by  levers.'^  He 
further  states  that  the  scaleni  and  the  serratus  anterior  are 
inspiratory  muscles,  and  that  they  prevent  the  diaphragm  from 
drawing  the  costal  cartilages  inwards.  This  is  also  illustrated  by 
drawings.*  Both  in  text  and  drawings  he  defines  the  internal 
intercostal  muscles  as  expiratory,  stating  that  they  proceed 
obliquely  upwards  and  forwards,  that  the  external  intercostal 
muscles  are  inspiratory  and  run  in  the  opposite  direction,  and  that 
the  intercostal  nerves,  arteries  and  veins  pass  between  the  ribs.^ 
The  thorax  expands  on  account  of  the  oblique  disposition  of  the  ribs 
and  of  the  bending  of  the  costal  cartilages,**  the  lower  ribs  move 
more  than  the  upper ;  but  in  the  case  of  irregular  breathing  Leonardo 
draws  attention  to  the  intervention  of  the  abdominal  muscles  \^dth 
action  on  the  intestines,  which  again  act  on  the  diaphragm." 

Light  sketches  appear  of  the  oblique  plane  of  the  superior 


1  Q.  u,  f.  1  r. 

-  Q.  i,  f.  4  V.    The  old  '  vena  arterialis  '  =arteria  pulmonalis. 

3  Q.  i,  f.  2  V.          4  Q.  i,  flf.  5  r.  and  8  r.  ^  q  [y  f  9  j. 

7  Q.  ii,  f.  16  V,  p.  35. 


Q.  ii,  f.  6v. 


PLA  ric    X  X  X  I 


u* 


-'l^'.Vo. -,.,„.. 

./.  r^.-.,  ^.    .^    ^^_^ ^ 

/ 

„    .>„..w   •>,v.^    . 

\ 

0  u  a  d  e  r  n  i  II  f  o .  3  v 

Dissection  of  coronary  vessels 


-i,,^  .,i««,  »-»•»» '^3j^•^r 


AW  (,«)»>*•> ^■~^—l~•••^»rrTT'> 


-v^mAiW* 


O  u  a  (1  c  r  n  i   II   f  o .   1  r 
Dissection  of  bronclii  and  bronchial  vessels 


LEONARDO  AS  ANATOMIST  169 

thoracic  aperture,  with  the  union  of  the  costal  cartilages  with  the 
sternum,^  and  also  of  the  cartilages  of  the  lower  ribs  which  form  the 
costal  arch  and  are  ranged  one  below  the  other,  like  a  part  of 
a  cable,  so  that  the  skin  may  more  easily  glide  over  the  cartilages 
when  they  move.  The  ribs  are  '  pivot-shaped  '  at  their  attach- 
ment to  the  vertebral  column  for  the  benefit  of  the  respiration.- 

Leonardo  has  observed  that  the  shoulders  move  in  breathing 
but  '  the  raising  of  the  shoulders  does  not  always  force  the  lungs 
to  inhale  '.  The  thorax  is  the  receptacle  for  the  spiritual  organs, 
the  abdomen  for  the  natural.  The  lungs  expand  and  contract 
continuously  in  all  directions,  but  mostly  downwards. '  Leonardo 
has  observed  a  calcified  focus  in  a  lung  and  meditates — as  this 
unique  observer  always  does  when  he  meets  anything  unknown 
to  him — over  the  causes  of  the  process.^  Emphasizing  the  re- 
cuperative power  of  Nature,  he  concludes  that  Nature  prevents 
a  break  in  the  bronchi,  by  the  thickening  of  the  substance  which 
becomes  cartilaginous,  and  forms  an  '  incrustation  Hke  the  shell 
round  a  nut '.  Inside  the  focus  is  found  '  dust  and  watery  humor  '. 
From  the  passage  containing  this  description,  he  draws  a  line  to 
the  focus  on  the  drawing.  In  another  manuscript  which  also  treats 
of  the  lungs  he  remarks  that  '  dust  is  injurious  \^  so  that  he  seems 
to  have  fixed  on  the  idea  of  diseases  of  the  lung  as  originating 
from  this  cause. 

Leonardo  points  out  that  the  cartilaginous  ring  of  the  trachea, 
which  is  elastic  as  a  spring,  is  incomplete  at  the  back,  where  the 
oesophagus  enters.^  '  But  the  trachea  contracts  in  the  epiglottis 
in  order  to  condense  the  air  which  seems  animated  from  the  lungs 
in  order  to  form  various  tones  of  voice.' '  He  considers  that  the 
relation  of  the  trachea  to  the  formation  of  the  voice  must  be  studied 
and  he  describes  which  and  how  many  muscles  act  on  the  larnyx 
in  phonation.  ^  '  And  thus ,  you  must  not  give  up  this  study  of 
the  voice  and  of  the  trachea  and  its  muscles  until  you  have 
acquired  full  knowledge  of  all  the  parts  contiguous  to  the  larynx 
and  of  their  functions  made  by  nature  for  the  modulation  of  this 
voice.  And  of  all  this  you  must  make  a  special  dra-vving,  sketching 
and  discussing  the  various  ^  parts.'  Then  resuming  his  experiments 
he  deals  with  various  phonetical  problems.^"  He  now  busies  him- 
self with  the  development  of  sound  and  shows,  both  in  text  and 

1  Q.  ii,  f.  6  V.  2  Q  iv^  f   1  r.  3  q  j^^  f .  3  r.  -»  Q.  ii,  f.  1  r. 

5  Q.  iii,  f.  1    V.  «  Q.  1,  f .  9  r.  '  Q.  i,  f.  o  v.  «  Ibid. 

«  Q.  i,  f.  9  r.  1"  Q.  iv,  f.  10  r.  and  v. 


170  LKOXAKDO   AS   ANATOMIST 

(liau  iiiL^--,  thill  (lie  palalc  divides  tlic  air  ciinciit,  so  that  it  goes 
paitly  thioiiLdi  the  nose,  partly  tliroiiglj  tlic  month.  He  dcscribea 
till'  position  ol  the  lips  and  tlu*  |)art  phiyed  by  the  soft  palate  in 
\\\v  formation  of  vowels  and  arranges  these  in  eonjnnetion  with 
various  consonants  in  tables.  He  compares  tlie  trachea  to  an 
organ-|)ipe,  and  tiiinks  that  the  voice  can  be  modulated  by  its 
IciiLrthening  and  shortening,  its  ex])ansion  or  contraction. 

Although  in  other  niaiuiseripts  Leonardo  has  reproduced  the 
larynx  very  clearly,  it  is  uncertain  how  exactly  he  understood  its 
function.'  He  does  not  use  the  word  larynx,  but  calls  it  sometimes 
the  '  trachea',  sometimes  the  '  uj)per  |)art  of  the  trachea',  or  its 
'  rin(j\  sometimes  the  'epiglottis'  or  the  'fistula  or  Hute,  i.e.  the 
place  where  the  voice  is  formed  '."^  He  states  that  fjy  the  dissection 
of  animals  he  will  make  an  experiment  of  pressing  the  air  in  and 
out  of  a  lung,  '  contracting  and  dilating  the  fistula,  the  generator 
of  their  voices  '. 

In  dealing  with  the  trachea  and  larynx  Leonardo  also  brings 
in  the  tongue,  which  consists  of  28  or  24  muscles,  but  he  '  notes 
how  they  transform  themselves  into  six  in  their  formation  in  the 
tongue  .  . .  and  further  it  must  be  demonstrated  where  such  muscles 
have  their  origin,  that  is  to  say  from  the  cervical  vertebrae,  where 
they  join  the  oesophagus,  and  some  from  inside  from  the  maxilla, 
and  some  from  the  outside  from  the  side  of  the  trachea  '.^  The 
tongue  takes  part  in  the  enunciation  and  articulation  of  syllables, 
sets  the  masticated  food  in  motion,  cleanses  the  mouth  and  teeth, 
'  and  its  principal  functions  are  seven,  i.  e.  extension,  retraction 
and  attraction,  thickening,  shortening,  dilation  and  straightening'. 
On  account  of  its  great  mobihty,  Leonardo  frequently  compares 
it  to  the  penis  :  '  but  here  you  might  perhaps  argue  with  the 
definition  of  the  membrum  which  receives  in  itself  so  much  natural 
heat,  that  it,  besides  its  thickening,  lengthens  very  much'.  The 
surface  of  the  tongue  in  the  eat  and  bovine  tribes  is  very  rough, 
and  as  an  illustration  of  this,  Leonardo  relates  the  following ; 
'  I  once  saw  a  lamb  being  licked  by  a  lion  in  our  town  of  Firenze 
where  there  are  always  twenty-five  or  thirty  of  them,  and  where 
they  are  bred  ;  this  lion  removed  with  a  few  strokes  the  whole 
skin  of  the  lamb,  and,  thus  denuded,  ate  it  up."  ^ 

1  FogU  A,  f .  3  r. 

2  See  C.  L.  Vangensten.  '  Leonardo  da  Vinci  og  fonetiken  ',  Videnskah'i- 
selskabets  Forhandlimjer,  No.  1,  1913. 

3  Q.  iv,  ff.  9  V.  and  10  r.  «  Q.  iv,  f.  9  v. 


PLATK    XXX  I  I 


'C^' 


Quaderni   I  I   fo.  9  v 
The  Semilunar  Valves 


'I  '         ,  VI 


-♦    f« 


Quaderni   I  \'   f  0 .  11  \ 

Above.     Glass  casts  with  valves  to  illustrate  action  of  semilunar 

valves. 
Below.     Diagrams  of  semilunar  valves;  to  the  right  the  eddies 

of  the  blood  are  shown. 


LEONARDO   A8  ANATOMIST  171 

Here  again  Leonardo  makes  a  deviation  in  his  train  of  thought. 
After  deaUng  with  the  rough  surface  of  the  leonine  tongue  on  one 
page,  on  the  next  his  thoughts  turn  for  a  moment  to  Florence, 
for  here  appears  a  lightly  sketched  representation  of  that  town  ^ 
in  the  form  of  two  inscribed  circles  joined  by  lines  which  go  to  the 
centre,  and  on  which  are  written  the  names  of  its  eleven  gates. 

In  no  less  than  three  of  the  Quaderni,  besides  other  manu- 
scripts, Leonardo  pursues,  with  surpassing  skill,  the  study  of 
the  heart  and  the  movement  of  the  blood  in  it  and  in  the  larger 
blood-vessels.  A  number  of  drawings  and  paragraphs  in  one  of 
the  Quaderni "  suggest  that  these  manuscripts  must  have  been 
written  in  his  early  days  as  an  author,  whilst  others  show  that  he 
had  dissected  and  made  much  progress  in  comprehension  of  the 
vascular  system.^  It  is  obvious  from  these  drawings  that  the 
representations  of  the  heart  are,  for  the  most  part,  based  on 
investigations  of  the  hearts  of  animals,  principally  cattle.  Occa- 
sionally however  drawings  of  the  human  heart  appear.  ^  In  several 
places  Leonardo  mentions  the  veins  and  arteries.  He  frequently 
indicates  by  the  word  '  veins  ',  both  veins  and  arteries — in  other 
words,  the  blood-vessels.  In  some  manuscripts  he  must  mean 
arteries  when  he  writes  '  veins ',  and  occasionally  it  is  doubtful 
whether  veins  or  arteries  are  implied.  He  draws  the  outer  surfaces 
of  the  heart  (Plate  xxxi),  and  by  longitudinal  and  transverse 
sections,  he  demonstrates  its  cavities,  their  form  and  projections 
(Plates  XXXIII  and  xxxiv),  with  the  trabeculae,  the  pectinati 
muscles  with  the  depressions  between  the  septum,  the  papillary 
muscles,  the  cordae  tendineae,  the  valves,  the  columnae  carneae, 
and  again  in  a  transverse  section  of  the  base  ^  he  shows  the 
venous  and  arterial  openings  with  their  similarly  disposed  valves 
(Plate  XXXIII,  upper  figure). 

Leonardo  draws  the  heart  in  the  shape  of  a  cone,  with  the 
base  upwards  and  to  the  right.  On  the  surface  of  the  heart  are 
seen  the  coronary  vessels,  arteries  as  well  as  veins.  These  '  he 
together,  the  arteries  deeper  than  the  veins,  but  some  of  the 
arterial  ramifications  lie  above  those  of  the  veins  \^  and  '  with 
regard  to  the  third  vein,  I  have  not  yet  seen  whether  it  has  an 
artery  with  it,  for  which  reason  I  shall  make  a  dissection  (really 
peel  off  the  flesh)  to  satisfy  myself  '.'     The  coronary  vessels  are 

1  Q.  iv,  f.  10  V.  2  Q  i  3  Q  ii   and  iv. 

*  e.  g.  Q.  ii,  f.  14  r.,  fig.  1.  ^  q   j^.   f    14  j.. 

«  Q.  ii,  f.  1  r.  '  Q   iv.  f.  13  v. 


172  LKONAKDO   AS   ANATOMIST 

smTomidrd  with  tat,  and  covered  by  tlie  pei-icardinm  wliicli  covers 
halt  the  width  of  the  ves.selH,  the  other  iialf  \h  covered  by  the 
flesh.'  Tiie  arteries  feed  the  heart's  substaiieo,''  and  spring  from 
the  aorta;"'  they  'issue  from  both  the  outer  oj)enings  of  th(;  left 
ventricle '.  By  this  is  perhaps  meant  Leonardo's  hemicycles, 
later  known  as  tiie  sinuses  of  Valsalva.  'J'he  coronary  veins  are 
(Milled  '  vftic,  ni're\*  probably  l)ecause  tliey  are  dark  in  colour  on 
account  of  their  venous  blood.  Jjconardo  describes  how  the  outer 
surface  of  the  heart  is  visibly  divided  by  the  coronary  vessels  ^ 
and  these  anastomose  at  the  apex." 

He  states  that  the  heart  has  four  ventricles,  two  larger  on  the 
right,  and  two  smaller  on  the  left.  The  two  lower  ones  lie  in  the 
heart's  substance,  and  the  two  upper  ones  outside  it.  He  opposes 
those  who  say  that  there  are  only  two  cavities  in  the  heart,  and 
maintains  that  if  one  means  that  the  two  right  and  two  left 
ventricles  each  only  form  one  cavity,  then  the  room  and  ante- 
room which  are  separated  by  a  small  door  are  only  one  room.' 
The  upper  or  outer  ventricles  should  in  this  case  answer  to  the 
ante-rooms  and  this  word  is  indeed  often  used  to  designate  them.® 
In  consequence  of  the  fact  that  most  of  Leonardo's  material  on 
the  subject  of  the  heart  is  derived  from  animals,  his  outer  or  upper 
ventricles  are  sometimes  to  be  taken  not  as  atria  but  as  auricles, 
and  he  occasionally  says  this  himself.  '  The  heart  has  four  ven- 
tricles, that  is  to  say,  two  upper,  called  heart-ears  ('  orechi  '), 
and  below  them  the  two  lower  ones  called  the  right  and  left 
ventricles.'  *  He  says  that  these  ears  of  the  heart  are  of  the  nature 
of  expanding  pockets,  so  as  to  receive  the  percussion  on  the 
movement  made  by  the  blood  when  it  is  forcibly  driven  out  of 
the  ventricles  when  these  contract,  and  he  compares  them  to  the 
bundles  of  wool  and  cotton  placed  on  the  bulwarks  of  a  ship  to 
soften  the  impact  of  shots  from  enemy  bombardment.^" 

It  seems  reasonable  to  assume  that  Leonardo,  who  has  dissected 
animal  as  well  as  human  hearts,  often  meant  atria  when  he  used 
the  words  '  upper  ventricles  ',  and  '  ears  '.  This  is  also  obvious 
from  a  drawing  and  observation  he  made  of  an  open  foramen 

1  Q.  ii,  f .  1  r.  2  Q  ii^  f  4  J.  3  Q  jj^  f  3  v^  4  Q.  ii^  f .  4  r. 

5  Q.  iv,  f.  13  V.  6  Q.  iv,  f.  14  V.  '  Q.  i,  f.  3  r. 

®  Holl  points  out  that  Leonardo  was  the  first  to  introduce  the  designation 
ventricles  for  the  cardiac  cavities  :  before  Leonardo,  various  other  expressions 
were  in  use,  as  sinus,  vacuitas,  or  concavitas  cordis. 

»  Q.  ii,  f .  17  V.  and  f.  3  v. 

1°  Q.  ii,  f.  3  r.    Here  is  one  example  of  the  many  images  in  which  Leonardo's 
work  is  so  rich. 


LEONARDO  AS  ANATO^MIST  173 

ovale.  '  I  have  found  from  (a)  in  the  left  to  (b)  in  the  right  ven- 
tricle a  perforation  which  I  here  note  to  ascertain  whether  it  also 
occurs  in  other  hearts.'  ^ 

The  muscles  of  the  heart  consist  of  longitudinal  and  transverse 
fibres.     In  all  the  four  ventricles  the  interior  muscles,  which  are 
adapted  for  contraction,  are  of  a  similar  nature.     The  surface 
muscles  on  the  other  hand  serve  only  the  lower  ventricles,  but 
the  upper  ones  have  a  continuous  membrane,  dilatable  and  con- 
tractable  ;  elsewhere  ^  he  states  that  the  upper  ventricles  could  not 
empty  themselves  if  they  could  not  fold  together,  and  if  they  had 
not  longitudinal,  oblique,  and  transverse  muscles,  able  to  contract. 
Leonardo  considers  and  represents  the  wall  of  the  left  ven- 
tricle as  much  thicker  than  that  of  the  right,"'  and  the  apex  of  the 
heart  to  be  formed  mostly  by  the  left  ventricle  ^  (Plate  xxxiv, 
lower  figure,  and  Plate  xxxvi,  left).     To  obtain  a  correct  idea  of 
the  shape  and  contour  of  the  heart's  cavities,  they  must  be  inflated 
before  dissection.  ^     One  can  then  find  '  cells  '  or  '  cavernosities  ' 
separated  by  rounded  walls  (i.  e.  the  trabeculae  and   pectinati 
muscles).     '  If  you  inflate  the  auricle  you  will  find  out  the  shape 
of  the  cells. '^     The  cavity  of  the  heart  is  divided  into  two  parts 
by  a  septum  in  which  are  pores,  meati,  for  the  passage  of  blood 
from  the  right  to  the  left  ventricle.    As  a  rule,  Leonardo  makes 
the  septum  quite  solid,  occasionally  with  indications '  of  the  meati, 
but  these  he  admits  he  was  unable  to  find  himself,  for  he  refers 
to  them  as  invisible.^ 

Musmili  papillares,  which  Leonardo  calls  the  muscles  of  the 
heart,  merge  '  near  the  valves '  into  the  cordae  (tendineae),  and  the 
valves  are  held  firmly  by  these  cords.  These  muscles  of  the  heart 
divide  into  two  parts,  each  having  its  own  cordae,  and  Leonardo 
has  noticed  that  the  cordae  are  fastened  to  different  parts  of  the 
cusps  of  the  valves.®  He  has  made  a  very  beautiful  drawing  of  the 
papillary  muscles  with  cordae,  fixed  to  the  tricuspid  and  bicuspid 
valves^®  (Plate  xxxiii,  upper  fig.,  and  Plate  xxxiv,  upper  fig.). 

In  some  of  his  draAvings  of  ventricles  Leonardo  sketches  the 
intraventricular  moderator  band,"  which  takes  its  origin  in  the 
septum  and  is  attached  at  the  base  of  a  papillary  muscle  or  a 
trabecula^^   (Plates    xxxiv    and    xxxvi)      This    band    he    called 

1  Qii,  f.  11  r.  2  Q.  i,  f.  4r.  3  Q.  ii,  f.  Hr. 

«  Q.  ii,  f.  4  r.  5  q  j^,  f.  13  r.  and  v.  «  Q.  iv,  f.  13  v. 

'  e.  g.  Q.  i,  f.  3  r.  s  q  j^.^  f  n  v.  »  Q.  ii,  f.  3  r. 

^»  Q.  iv,  f.  13  r.  and  v.,  f.  14  r.  "  Q.  i,  f.  14  r  ;  Q.  iv,  f.  13  r. 

12  Q.  iv,  f.  13  r. 


174  LlOONAinX)   AS   ANATOMIST 

catena,^  and  in  liis  opinion  it  serves  to  prevent  tin-  licait  dilating 
more  than  necessary,  for  witliout  this  strueture  the  heart  would 
(h'aw  too  much  blood  from  thosci  vessels  into  w  hich  it  had  previously 
throun  it  -  (Plates  xxxill  and  XXXIV). 

In  one  of  his  drawings  tlie  vena  eava  superior  and  inferior  are 
distinetly  seen  to  enter  the  right  auricle  separately.'  The  other 
drawino;s  of  these  ve.ssels  and  their  relation  to  the  heart  seem  to 
be  taken  from  animals.  To  the  j)ulmonary  artery  and  vein  he 
gives  the  old  names  of  vena  arterialis  and  artaria  venalis  resj)ectively. 

The  aorta  {vena  aorta  or  arteria  aorto)  comes  from  the  left 
ventricle.*  'The  right  ventricle  has  two  orifices,  one  in  the  vena 
aorto,  and  vvlK'n  the  heart  dilates  in  the  left  ventricle  its  base 
contracts  to  close  the  door  of  the  arteria  aorto.'  ^  The  other 
orifice  is  '  the  arteria  venalis  (pulmonary  vein),*  and  goes  from  the 
heart  to  the  lung '.  Leonardo  is  here  indefinite.  He  does  not 
mention  the  left  auricle. 

On  one  occasion  Leonardo  calls  the  pulmonary  artery  '  the 
door  of  the  lung  '.  Under  the  heading  On  the  names  of  the  vessels 
of  the  heart  he  says,  in  fact,  '  the  door  of  the  lung,  and  it  is  called 
vena  arterialis,  and  it  is  named  vena,  because  it  conveys  the  blood 
to  the  lung.'  Leonardo  has  here  erased  these  last  words  to  the 
lung,  but  that  he  meant  that  the  pulmonary  artery  carries  blood 
to  the  lung  seems  obvious  from  the  continuation  of  the  passage  : 
'  And  it  has  three  valves  which  open  from  within  outwards  (val- 
vulae  semilunares)  with  perfect  closure,  and  these  are  in  the  right 
ventricle.'  '  The  dominating  position  attributed  by  him  to  the 
aorta  is  seen  from  the  following  passage  :  '  And  in  the  middle  of 
the  base  of  the  heart  is  the  source  or  base  of  the  aorta,  founded  in 
the  centre  of  the  heart's  base,  having  power  over  the  state  of  this 
heart's  base  as  the  latter  has  power  over  the  animal's  life.'  ^ 

Leonardo  deals  often  with  the  valves  of  the  heart.  The  atrio- 
ventricular valves  are  formed,  according  to  Leonardo,  by  the 
endocardium  above  and  the  cordae  tendineae  below  ;   these  may 

1  Q.  ii,  f.  4  V. 

2  HoU  points  out  that  Leonardo  was  the  first  to  observe  these  fibres  passing 
through  the  ventricular  cavities  and  suggests  that,  in  honour  of  their  discoverer, 
they  should  be  called  Leonardo  da  Vinci's  columnae  carneae.  Tawara  in  1908 
first  pointed  out  that  these  fibres  form  bridges  through  which  the  fibres,  the 
atrio-ventricular  bundle  of  His,  reach  from  the  septum  to  the  papillary  muscles. 

3  Q.  ii,  f.  14  r. 

*  Q.  ii,  f.  2  v.  HoU  points  out  that  Leonardo  must  here  have  written  right 
for  left.  5Q,  ii^f.  13v.  «  Q.  ii,  f.  2  v. 

"  Q.  ii.  f.  2  V.  8  Q.  iv,  f.  14  V. 


LEONARDO  A8  ANATOMIST  175 

stretch  from  one  of  the  papillary  muscles  to  two  of  the  cusps  of 
the  valve.^  Valvulae  semilunares  are  portrayed  both  open-  and 
closed.'^  Leonardo  describes  how  the  inside  of  the  artery  (i.  e. 
either  of  the  aorta  or  pulmonary  artery)  is  covered  by  a  thin 
membrane  (intima)  which  merges  into  and  forms  one  side  of  the 
valves,  the  other  side  of  the  valve  being  formed  of  another  layer 
of  the  pannicle.*  A  similar  pannicle  is  found  in  the  ventricles 
(endocardium)  and  in  the  pericardium.  The  shape  of  the  closed 
semilunar  valves  seen  from  above  and  below  are  so  beautifully 
reproduced  that  they  must  have  been  copied  after  the  large  vessels 
had  been  filled  up  with  a  solidifying  substance.  Leonardo  indeed 
here  remarks  :  '  but  first  pour  wax  into  the  ports  of  an  ox  heart, 
so  that  you  can  see  the  true  form  of  these  doors.'  ^ 

In  his  opinion  the  valves  and  the  roots  of  the  great  arteries 
are  enclosed  in  the  substance  of  the  heart,  so  that  the  blood  when 
it  presses  against  the  closed  valves  will  not  destroy  these,  but 
will  break  its  impetus  against  the  walls  of  the  blood  vessels  by 
dilating  them.®  And  in  dealing  with  the  closing  of  the  semilunar 
valves  when  the  blood  passes  over  them,  he  finds,  from  his  physico- 
mathematical  reflections  that  three  aorta-valves  are  more  satis- 
factory than  four,'  for  if  their  number  were  more  than  three,  their 
angles  or  triangles  would  be  weaker  than  those  ®  formed  by  three 
valves. 

It  is  difficult  to  judge  how  Leonardo  pictured  to  himself  the 
working  of  the  heart,  the  movement  of  the  valves  and  of  the  blood. 
He  is  not  in  the  least  clear  in  his  pronouncements  concerning  them, 
and  his  remarks  on  these  points  are  spread  over  many  leaves  of 
manuscript.  He  often  says  that  when  the  ante-chambers,  the 
upper  ventricles  (i.e.  auricles),  contract,  the  heart-chambers,  the 
lower  ventricles,  expand,  and  vice  versa,  e.g.  '  On  the  two  lower 
ventricles  situated  in  the  root  of  the  heart ;  their  dilatation  and 
contraction  are  made  at  one  and  the  same  time  through  the  tlux 
of  the  flood,  and  the  reflux  of  the  blood  is  made  at  one  and  the 
same  time^  succeeding  the  first,  through  the  reflux  in  the  upper 
ventricles,  situated  above  the  root  of  this  heart.'  ^  The  movement 
of  the  blood  at  the  alternating  dilatation  and  contraction  of  the 
ui)per  and  lower  ventricles  is  thus  compared  with  ebb  and  flow. 
By  the  contraction  of  the  auricles,  the  blood  is  driven  through  the 
atrio-ventricular  openings  into  the  ventricles  which  open,  causing 

1  Q.  ii,  f.  3  r.  2  q   ^j   £f   3  ^-   ^^^^^  4  r  3  q   ii^  f.  9  v. 

*  Q.  iv,  f.  14  V.  5  Q  ii  f   12  r.  «  Q.  iv,  f.  14  v. 

'  Q.  iv,  f.  12  r.  8  Q   ^y  f    12  V.  «  Q.  ii,  f.  4  v. 


17()  LEONARDO   AS  ANATOMIST 

the  semilunar  vaKcs  to  close.  When  tlic  vciitricle.s  contract,  some 
blood  ictyinis  lo  llic  itiilc-cliainht'rs  before  the  atrio-ventricular 
valves  have  closed  entirely  ;  '  the  latter  when  so  stretched  in- 
crease somewhat  in  size  and  ajjproach  one  anotlKT,  causing  ulti- 
mately a  complete  closure  both  of  the  right  and  left  atrio-ventri- 
euiar  orifices.'^  With  the  systole  of  the  right  ventricle,  another 
j)ortion  of  the  blood  goes  through  the  j)ulmonary  artery  to  the 
lungs,  while  a  third  ])ortion  goes  through  the  septum  into  the  left 
ventricle.^  Thus  less  blood  is  driven  back  from  the  right  ventricle 
to  the  right  auricle  than  goes  from  the  auricle  to  the  ventricle,  and 
the  right  auricle  has  its  quantity  of  blood  made  good  from  the 
vena  cava  inferior,  '  through  the  liver,  the  treasurer,  the  generator 
of  blood '.  '  The  blood ',  which  comes  to  the  lungs,  '  gives  without 
liindrance  the  necessary  nourishment  to  the  pulmonary  veins, 
where  the  blood,  after  it  has  been  refreshed  in  the  lung,  returns 
for  the  most  part  to  refresh  the  blood  left  in  the  ventricle  w^here 
it  divided.'  ^  What  Leonardo  means  by  this  is  obscure,  as  he  does 
not  mention  through  which  vessels  the  blood  returns  to  the  heart. 
'  In  the  lungs  the  arteries  which  are  connected  with  the  minute 
branches  of  the  bronchi  absorb  the  freshness  of  the  air  entering 
the  lungs.'  ^ 

ElscM'here  he  asks  :  '  Whether  the  pulmonary  veins  send  back 
the  blood  to  the  heart  when  the  lung  contracts  at  the  expulsion 
of  the  air',*  and  he  says  that  the  contraction  of  the  diaphragm 
compels  the  lungs  to  expand, '  which  occurs  in  order  that  they  may 
absorb  the  air  with  which  the  veins  (vena  arterialis  =  pulmonary 
artery)  proceeding  from  the  heart  may  refresh  themselves.'  The 
blood  is  heated  in  the  heart's  cavity,  part  of  it  evaporating  (spiritus 
vitalis),  and  this  vapour,  mingled  with  dense  moisture,  is  excreted 
through  the  farthest  ends  of  the  capillaries  (' vene  chapillari ')  from 
the  skin  in  the  form  of  perspiration.'  *  When  the  left  ventricle 
contracts,  the  blood  goes  through  the  aorta  ^  ('the  upper  vessel'), 
and  the  wave  of  blood  thus  formed  goes  through  all  the  arteries,^^ 
and  with  the  pulsation  of  the  blood  in  the  heart,  which  closes  the 
valves,  '  a  tone  is  created  which  goes  through  every  artery  and 
which  the  ear  often  hears  in  the  temples '." 

By  drawings  as  well  as  descriptions,  Leonardo  discusses  the 
flow  of  the  blood  from  the  left  ventricle  through  the  opening  of 

»Q.  ii,  f.  3v.  2  Q  ji   ft   3i.    8v.,  11  r.,  and  12r.  ^Q.u,f.l7v. 

4  Q.  ii,  f.  4  V.  5  Q   ii^  f    11  J..  6  Q.  i,  f.  o  r.  '  Q.  i,  f.  4  v. 

8  Q.  ii,  f.  11  r.  9  Q.  ii,  f.  17  v.  i«  Q.  ii,  f .  13  v.         ^^  Q.  ii,  f.  3  r. 


n 


O  u  a  d  e  r  n  i    V    To .   14  r 
Details  t)f  cardiac  anatomy 


'♦♦A*  '»^<rv'|  vori  v| 


Ouaderni  I\'  fo.  8 


LEONARDO   A8  ANATOMIST  177 

the  aorta  and  its  branches.^  The  semilunar  valves  open  at  the 
ingress  of  the  blood  and  close  with  its  withdrawal.  He  theorizes 
as  to  how  far  the  arterial  ostia  open  only  with  the  central  part  of 
the  semilunar  valves,  and  to  what  extent  the  openings  of  the 
heart  could  have  closed  by  mere  muscular  action  without  valves  : 
he  comes  to  the  conclusion  that  the  closure  of  the  heart's  openings 
proceeds  both  better  and  more  quickly  with  the  aid  of  the  valves 
than  if  it  occurred  by  action  of  the  heart's  substance. 

When  the  left  ventricle  contracts,  the  blood,  as  already  stated, 
flows  into  the  aorta  ;  its  speed  is  there  varied  proportionately  to 
the  calibre  of  the  vessel.  When  the  wave  of  blood  enters  the 
aorta,  the  centre  part  of  the  wave  which  goes  directlj-  upwards  is 
higher  than  the  sides,  the  impetus  of  which  dissipates  itself  by 
the  lateral  motion.  Leonardo  proves  that  in  this  the  blood  acts 
like  other  fluids,  demonstrating  both  by  words  and  drawings  the 
action  of  water  when  it  runs  out  of  a  vertical  and  a  horizontal 
tube.'^ 

During  his  deliberations  over  the  movement  of  the  blood  in 
the  ostium  aortas,  and  above  its  semilunar  valves,  Leonardo  made 
several  experiments  with  models.  His  wax  castings  of  the  heart 
have  already  been  mentioned,^  and  in  this  connexion  he  says  : 
'  A  form  of  gypsum  to  be  inflated,  and  a  thin  glass  within,  and 
then  break  it  from  head  to  foot  '  ;  and  :  '  The  form  of  the 
glass,  to  see  in  the  glass  what  the  blood  does  in  the  heart  when 
it  shuts  the  openings  of  the  heart'."*  In  order  clearly  to  under- 
stand the  movement  of  the  blood  in  the  heart,  Leonardo  thus 
first  made  a  wax  cast  of  the  ventricles  and  their  vessels,  over 
this  he  made  a  gypsum  cast,  and  from  this  a  glass  cast.  Through 
this  glass  cast  he  has  examined  the  vortices  made  by  the  blood 
when  it  is  driven  out  by  the  systole  into  the  aorta  and  pulmonary 
artery,  as  shown  in  some  of  his  drawings^  (Plate  xxxn).  The 
semilunar  valves  close  during  these  vortices,  and  the  walls  of  the 
blood-vessels  protrude  into  the  '  semiventricles  '  or  '  hemicycles  ' 
(sinuses  of  Valsalva). 

Leonardo,  however,  finds  it  difficult  to  gauge  to  what  extent 
this  actually  occurs.  He  says  :  '  It  is  doubtful  whether  the 
percussion  caused  by  the  forcible  movement  in  the  front  of  the 
upper  arch  of  the  hemicycle  divides  into  two  parts,  of  which  one 
goes  upwards  and  the  other  backwards,  and  this  doubt  is  subtile 

1  Q.  iv,  f.  11  r.  and  v,  f.  12  r.  2  q.  [y^  f   u  y. 

3  Q.  ii,  f.  12  r.  «  Q.  ii,  f.  C  v.  ^  q  [[   g  12  r.  and    13  v. 


ITS  IJOOXAKDO    AS    ANATOMIST 

and  (lilHcnlt  to  clucidato.'  '  He  tlicii  makes  aiiollier  expeiiineiit  : 
'  Make  tliis  experiment  in  a  glass  and  move  .  .  .  the  ])arniienlae 
(i.e.  tlie  valves)  about  in  it  ' -.  And  now  his  doubt  has  vanished  ; 
he  has  eompleted  his  experiments  and  has  come  to  the  following 
eonclnsions  :  Wlien  the  l)lood  enters  tlie  hemieyeles,  it  strikes  the 
wall  of  the  aorta  and  divides  at  the  topmost  edge  of  the  hemicycle 
into  an  ascending  and  a  descending  stream.  The  descending  part 
makes  a  spiral  curve,  follows  the  concavity  of  the  hemicycle,  and 
percolates  tlu'ough  its  base  ;  it  then  follows  the  surface  of  the 
semilunar  valve,  stretches  the  valve  and  closes  it  against  the 
other  valves,  the  stream  then  turns  upwards  in  a  retrograde 
movement  and  ends  in  a  reflex  vortex.'  The  ascending  part  of 
tlie  blood-stream  also  makes  a  whirling  motion,  but  in  the  other 
direction.  This  vortex  again  forms  other  vortices,  which  gradually 
decrease  until  '  the  impetus  consumes  itself  '.  When  the  blood 
by  the  systole  of  the  left  ventricle  is  driven  through  the  mouth 
of  the  aorta,  it  strikes  against  the  blood  over  the  semilunar  valves, 
and  '  this  concussion  shakes  all  the  arteries  and  jjulses  distributed 
throughout  the  body  '.^  The  systole  collapses  simultaneously  with 
the  concussion  of  the  apex  and  the  thorax,  also  with  the  heat  of 
the  pulse,  and  the  entry  of  the  blood  into  the  auricle^  (Plates 
xxxTi  and  xxxiv). 

One  must  investigate  the  relations  of  the  recurrent  nerve  to 
the  heart,  he  tells  us.  to  see  whether  this  nerve  lends  movement  to 
the  heart,  or  whether  the  heart's  movement  is  spontaneous.®  Its 
dilatation  and  contraction  are  spontaneous,  he  concludes,  and 
these  movements  occur  on  the  heart's  longitudinal  axis. 

In  the  ventricular  hollows,  between  the  trabeculae  and  the 
pectinati  muscles,  to  which  we  have  already  referred,  the  blood 
is  driven  round  in  a  whirling  movement,'  and  because  it  does  not 
meet  any  edges  or  corners  this  movement  acquires  '  its  vertiginous 
impetus  ',  which  causes  heat,  and  this  can  become  so  great  as  to 
cause  suffocation.  Leonardo  says  that  he  has  witnessed  such  an 
occurrence  in  the  case  of  a  man  whose  heart  '  broke  '  as  he  fled 
from  the  enemy,  a  blood-stained  sweat  exuding  from  all  the  pores 
of  his  skin.  Leonardo's  thought  then  turns  to  the  general  and  vital 
purpose  of  heat,  and  he  states :  '  And  so  heat  gives  hf e  to  all  things, 
just  as  one  sees  that  the  w^armth  of  the  hen  and  turkey  hen  gives 

1  Q.  ii,  f.  13  V.  2  Q  i^.  f  11  V 

^  It  seems,  to  judge  from  fol.  11  r.,  par.  11,  and  fol.  11  v.,  par.  11,  that 
Leonardo  means  the  sinus  of  Valsalva.  ■*  Q.  iv,  f.  11  v. 

5  Q.  iv,  f.  11  r.  «  Q.  iv,  f.  7  r.  '  Q.  iv,  f.  13  r.,  par.  i:i. 


P  L  A  T  !■:    X  X  X  I  \' 


\/^  - — — ^  x^'/«:^%i' 


fS^ 


rjvw- 


Q  LI  a  d  e  r  n  i   II   f"o .   1 2  r 

Right  ventricle  pulmonaiy  artery  and  mtis- 
ciill  papillarcs.  The  eddies  of  blood  are  shown 
around  the  semilunar  valves. 


o 


\^- 


^ 


•w 


178 


Ouadcrn  i   II   to.    141- 
Ventricles,  right  auricle,  and  great  vessels 


LEONARDO  AS  ANATOMIST  179 

life  and  birth  to  their  chickens,  and  the  sun  when  it  returns  gives 
hfe  and  blossoming  to  all  fruits.'  ^ 

Leonardo  endeavoured  also  to  study  the  movement  of  the 
living  heart.  He  relates  that  when  pigs  were  killed  in  Tuscany, 
the  animal  was  turned  on  its  back,  fastened  securely,  and  an 
instrument  called  a  '  spillo  ',  used  to  draw  wine  from  casks,  is 
thrust  into  its  heart.-  He  observes  that  if  it  enters  the  heart  the 
instrument  begins  to  move  :  at  the  diastole  its  point  goes  upwards, 
and  its  handle  downwards,  with  the  shortening  of  the  heart, — the 
contrary  with  its  lengthening.  At  last,  when  the  heart  has  ceased 
to  move,  the  handle  becomes 
stationary  in  the  exact 
middle  of  the  two  extremes. 
During  the  experiment  Leo-  M 
nardo  estimated  the  length 
of  the  movements.     '  And  t.     .^     ^  •      ^  *  t         i       *i    u    _^ 

Fig,  2.     An  experiment  oi  Leonardo  on  the  heart. 

I    have   seen    this    several 

times  and  taken  such  measurements,  and  left  such  an  instrument 
in  the  heart  until  the  animal  was  cut  up.'  Leonardo  demonstrates 
the  experiment  by  draAvings,  and  points  out  that  the  movements 
of  the  instrument  do  not  continue  equal  in  extent,  giving  reasons 
for  this  (Fig.  2). 

Of  all  the  bodily  movements  Leonardo  evidently  found  that 
of  the  heart  and  vascular  system  the  most  perplexing.  To  this 
question  he  returns  again  and  again,  expending  on  it  much  of 
his  time,  his  art  of  dissection,  his  keen  observation,  and  his  know- 
ledge of  the  laws  of  physics.  He  seeks  to  elucidate  this  theme 
with  question  and  counter-question  directed  from  every  point. 
He  controverts  actual  authors  and  fancied  antagonists,  and  his 
drawings,  experiments,  and  deliberations  tell  their  tale  of  his 
unceasing  efforts  to  reach  the  ultimate  truth  concerning  this 
abstruse  problem.  The  fact  that  more  than  a  quarter  of  all  the 
anatomical  and  physiological  drawings  in  the  six  Quaderni  deal 
with  the  heart  and  its  cavities  shows  how  intense  was  his  con- 
centration on  this  subject,  and  it  is  evident  from  the  folloAving 

^  It  is  extremely  interesting  to  follow  Leonardo's  train  of  thought  in  this 
manuscript.  Par.  iii  reaches  nearly  to  the  edge  of  the  manuscript ;  it  is  therefore 
evident  that  he  did  not  intend  to  write  anything  further,  but  his  thoughts  turned 
to  the  general  value  of  heat,  and  he  made  a  note  of  them  (par.  iv)  in  the  narrow 
margin  at  the  side  of  par.  iii.  From  this  par.  iv  he  drew  a  line  to  the  foot  of 
par.  iii  to  indicate  the  order  in  which  they  should  be  read.    See  Plate  xxxvi. 

2  Q.  i,  f.  6r. 


LSO  LKONAIiDO   AS   ANATOMIST 

passajiii'  how  iit'cc.s.sarv  In*  tluni^lit  it  to  use  drawings  as  well  as 
words  for  the  purpose  of  deiuonstration.  '  With  what  words  will 
you  describe  this  heart  so  that  you  do  not  fill  a  book  ;  and  the 
more  minutely  and  elaborately  you  describe  it,  the  more  you 
will  confuse  the  mind  of  the  listener,  and  you  will  ever  require 
a  commentator  or  to  revert  to  experience,  which  in  your  case  has 
been  very  short,  and  explain  few  things  concerning  the  subject 
in  its  entirety  about  which  you  wish  full  knowledge  '  ;  ^  and  it  is 
in  connexion  with  this  subject  that  he  exclaims  :  '  Give  an  address 
on  the  shame,  which  is  necessary  for  the  students,  impeders  of 
anatomy  and  abbreviators  thereof,"  nay  not  abbreviators  but 
destroyers  should  they  be  called  who  curtail  such  a  task  as  this.'  ^ 
To  judge  from  the  Quaderni,  the  main  results  of  Leonardo's 
research  concerning  the  working  of  the  heart  may  be  stated  as 
follow^s  :  At  the  contraction  of  the  auricles  the  blood  flows  through 
the  venous  ostia  into  the  ventricles.  At  the  systole  of  the  ventricles 
the  blood  goes  out  into  the  pulmonary  artery  and  the  aorta.  By 
means  of  the  pulmonary  artery  the  blood  goes  from  the  right 
ventricle  to  the  lungs,  from  where  it  returns  '  refreshed  '  to  the 
heart — by  which  vessels  is  not  stated.  From  the  left  ventricle 
the  blood  is  driven  into  the  aorta  and  from  it  into  all  the  arteries. 
Towards  the  skin  it  passes  into  the  '  capillary  veins  '.  Blood  enters 
the  right  auricle  by  the  vena  cava. 

Leonardo  has  not  given  any  clear  description  of  the  circulation, 
his  comments  on  the  subject  being  disconnected  and  incomplete. 
He  was  not  able  entirely  to  emancipate  himself  from  the  old  idea 
of  the  passage  of  the  blood  from  the  right  ventricle  through  the 
septum  into  the  left  ventricle,  although  he  himself  seems  doubtful 
about  the  truth  of  it,  for  he  says  that  the  pores  in  the  septum 
are  invisible.  He  likewise  maintains  that  with  the  systole  of  the 
ventricles,  some  blood  returns  to  the  auricles  until  the  atrio- 
ventricular valves  have  closed  entirely.  On  the  other  hand,  one 
must  remember  that  Leonardo  has  not  given  any  systematic 
expose  of  the  subject  ;  his  remarks  are  distributed  over  many 
years  and  many  manuscripts.  Nor  is  it  surprising  that  Leonardo, 
who  was  no  physician,  and  w^ho  occasionally  fell  short  in  the 
matter  of  proportion,  of  which  as  an  artist  he  made  daity  use, 
should  be  incomplete  and  obscure  in  dealing  with  one  of  the  most 
difficult  physiological  problems.  It  is  also  to  be  noted  that 
Leonardo  did  not  seek  to  pubhsh  the  results  of  his  research — 
it  is  only  comparatively  recently  that  they  have  been  found  in 
1  Q.  ii,  f.  1  r.  2  Q.  i^  f.  4  V.  3  Q   i   f  4  r. 


^!^- 


X 


X 


01      'o 


o    -5 


r    -1 


o     5^ 


LEONARDO  AS  ANATOMIST  181 

his  manuscripts.  It  is  therefore  possible,  in  spite  ot  errors  and 
omissions,  that  he  had  a  fairly  correct  conception  of  the  circula- 
tion. It  is  certain  that  in  the  Quaderni  he  beheld  the  Promised 
Land — that  he  began  to  enter  it  seems  evident  when  one  compares 
the  Quaderni  with  the  following  statements  in  the  Fogli : 

'  By  the  ramification  of  the  veins  in  the  mesentery,  the  food 
is  drawn  from  the  corruption  of  the  aliments  in  the  intestines, 
and  eventually  it  returns  by  the  ultimate  ramifications  of  the 
artery  to  these  intestines  .  .  .'  ;  and  again,  '  the  origin  of  the  sea 
is  the  contrary  of  that  of  the  blood,  for  the  sea  receives  in  its 
bosom  all  the  rivers,  which  are  produced  only  by  the  vapours  of 
water,  risen  into  the  air  :  the  sea  of  the  blood  is  the  cause  of  all 
the  veins.  The  aorta  is  only  one  which  subdivides  into  as  many 
principal  branches  as  there  are  principal  parts  to  be  nourished, 
branches  which  continue  to  ramify  ad  infi7iitum.''  ^ 

From  this  it  may  be  inferred  that  Leonardo  came  very  near 
to  the  conception  of  the  circulation  of  the  blood. 

The  drawings  of  blood-vessels  in  the  Fogli  are  so  beautiful  that 
Leonardo  must  have  prepared  the  vessels  by  injections.  Many  of 
those  in  the  Quaderni  date  from  an  earlier  period.  A  large  and  very 
fine  full-page  drawing  in  one  Quaderni,^  named  the  'Vessel-tree' 
and  'Spiritual  Parts',  is,  however,  not  very  accurate,  although  the 
three  great  blood-vessels  springing  from  the  arch  of  the  aorta  are 
correctly  rendered  (Plate  xxxv).  His  advice  on  the  study  of  the 
blood-vessels  is,  '  Bisect  the  heart,  liver,  lungs,  and  kidneys,  so 
that  you  may  be  able  to  portray  the  complete  ramification  of  the 
blood-vessels  '.  Below  a  very  rough  sketch  of  the  vascular  system 
he  writes,  under  the  heading  Anatomia  venarmn  :  '  The  vascular 
system  must  be  treated  as  a  whole  as  Ptolemy  represented  the 
world  in  his  cosmography.  Later  the  blood-vessels  of  each  part 
must  be  described  separately  and  from  various  aspects.  Study 
the  ramifications  of  the  blood-vessels  froin  the  back,  the  front, 
and  the  sides,  otherwise  you  cannot  give  the  true  information  as 
to  their  ramifications,  form,  and  position.'  ^  Elsewhere  he  gives 
a  beautiful  and  quite  correct  representation  of  the  subcutaneous 

^  Fogli  A,  f.  4  r.  Here  is  written  '  la  vena  ',  but  there  is  no  reason  why  vena 
should  not  here  mean  vessel,  that  is  aorta,  as  it  does  in  Q.  i,  f.  1  r.,  for  example, 
where  Leonardo  calls  the  abdominal  aorta  and  the  vena  cava  inferior  le  vene 
massime,  and  in  Q.  ii,  f.  2  v.,  where  he  deals  among  other  things  with  the  aorta 
under  the  heading  '  de  nomi  delle  vene  del  chuore  ',  which  is  translated  as  '  On  the 
names  of  the  vessels  of  the  heart  '.  In  the  same  place  Leonardo  calls  the  aorta 
*  Vena  aorto  '. 

'  Q.  v.  f.  I  r.  3  Q.  V.  f.  2  r. 

2331  -     -NT 


1S2  JJ':()NAKI)()   AS   ANATOMIST 

veins  of  the  t^roin.*  One  sees  here  the  union  of  tlio  vena  saphaui 
iiKKpia  and  tlie  vena  fdiiorali.s,  wliicli  latter  is  depieted  as  lyini^ 
mesial  to  the  arteria  femoralis.  To  this  figure  the  following 
passage  is  subjoined  :  '  From  the  soft  parts  (anguinaie)  of  the 
arms  and  tliighs  go  veins,  whieh,  branching  from  the  main  veins, 
traverse  the  body  between  the  skin  and  the  flesh.  And  remember 
to  note  how  the  arteries  part  from  the  eomj)any  of  the  veins  and 
nerves.'  The  vena  dor  sails  penis  also  appears  on  the  drawing,  and 
the  remark  :  '  There  are  two  kinds  of  vein  ramifications,  simple 
and  compound  ;  it  is  the  simple  one  which  continues  dividing 
itself  indefinitely.  A  compound  vein  is  one  which  is  formed  by 
two  branches,  as  one  sees  n.m.  and  m.o.  branches  from  two  veins 
which  unite  at  m.  and  form  the  vein  m.p.  which  goes  to  the  penis.' 
This  sketch  of  Leonardo's,  like  many  others  of  his  anatomical  draw- 
ings, might  well  be  placed  in  a  modern  text-book  (Plate  xxxiii). 

One  would  expect  Leonardo's  study  of  proportion  -  to  be  dis- 
cussed in  Trattato  delta  Pittura,  a  work  which  is  composed  of 
extracts  from  various  of  his  manuscripts,  but  it  is  not.  In  that 
work  the  fact  that  Nature  never  makes  two  individuals  exactly 
ahke  is  emphasized,  the  inference  being  that  one  cannot  draw  all 
one's  figures  from  the  measurement  of  a  single  subject.  Only 
a  few  special  measurements  appear  in  this  book.  The  manu- 
scripts constituting  the  opening  section  of  one  of  the  Quaderni  ^ 
contain  the  most  important  part  of  Leonardo's  studies  of  the 
proportion  of  an  adult.  ^  These  are  sometimes  rather  obscure, 
some  of  the  points  of  measurement  being  represented  by  letters 

^  Q.  iv,  f.  8r. 

-  The  study  of  proportion  is  the  teaching  concerning  a  harmonious  relation 
between  the  body  and  its  parts  stated  in  figures  formulated  for  practical  as  well 
as  artistic  requirements.  From  ancient  times  artists  have  sought  a  basic  measure- 
ment, a  module,  by  which  they  could  establish  a  standard,  i.  e.  the  normal 
length  and  breadth  of  the  body  and  its  parts,  and  the  schedule  used  has  been 
called  a  '  canon  '.  The  length  of  the  head,  the  face,  the  hand  and  the  foot,  have 
all  been  used  for  the  purpose,  and  the  length  of  the  body  and  the  limbs  deducted 
from  these.  The  Egyptian  canon  seems  to  have  been  calculated  from  the  length 
of  the  middle  finger,  the  length  of  the  body  being  19  middle  fingers.  Judging 
from  the  Doryphorus  of  Polycleitus,  the  Greek  canon  may  be  taken  from  the 
Egyptian,  or  as  some  think,  from  the  length  of  the  head  which  should  go  eight 
times  into  the  length  of  the  body.  With  Albrecht  Diirer  the  length  of  the  body 
ranges  from  six  and  a  half  to  eight  times  the  length  of  the  head.  According  to 
^Michael  Angelo's  canons  the  length  of  the  body  seems  to  be  between  nine  and 
ten  times  the  length  of  the  head.  ^  Q.  vi,  ff.  1-12. 

^  Leonardo  states  (see  Richter,  The  Literary  Works  of  Leonardo,  dsc,  ii, 
p.  109)  that  he  will  describe  the  proportions  of  the  adult  man  and  woman,  but 
no  orderly  exposition  of  these  is  known  to  have  been  written  by  him. 


LEONARDO  AS  ANATOMIST  183 

which  do  not  appear  in  the  adjacent  sketches.  He  also  uses  for 
purposes  of  measurement  points  which  vary  in  different  individuals, 
for  instance,  the  margin  of  the  hair,  and  some  of  his  text  and  draw- 
ings  are  difficult  to  interpret.  He  is  also  liable  to  designate  the  same 
part  by  different  terms,  thus  the  base  of  the  nose  is  named^we  di  soto 
del  naso,  principio  del  naso,  and  again,  nasscimento  di  sotto  del  naso.^ 

Like  many  contemporaries,  as  well  as  earlier  and  later  artists, 
Leonardo  made  for  himself  a  canon  of  proportion,  and  as  a  basis 
for  this  he  took  sometimes  the  length  of  the  head,  sometimes  that 
of  the  face  or  of  the  foot,  but  he  also  made  use  of  others.  Thus 
he  tells  us  that  the  entire  height  is  four  times  the  breadth  of  the 
shoulders,  and  again,  that  four  times  the  breadth  of  the  shoulders 
equals  only  the  distance  from  the  sole  of  the  foot  to  the  base  of 
the  nose.  In  one  manuscript  the  head  is  the  length  of  the  hand, 
in  another  it  is  the  face  that  is  of  this  length.  One  gathers  from 
such  contradictions  that  Leonardo  has  measured  various  subjects 
of  different  heights  and  proportions. 

It  is  thus  by  no  means  easy  to  follow  Leonardo's  study  of 
proportion.  The  manuscripts  containing  this  material  are  evi- 
dently a  collection  which  he  intended  to  revise,  for  here — as 
elsewhere  in  the  abundant  material  that  he  has  left  behind  him — 
he  deals  several  times  with  the  same  subject,  probably  at  different 
periods  and  with  different  models,  and  jots  down  his  findings 
without  putting  them  in  order,  so  that  we  do  not  know  which 
of  his  measurements  are  individual  and  which  general.  A  resume 
of  the  partially  worked-up  sections  of  Leonardo's  study  of  pro- 
portion may,  however,  be  attempted. 

Bases.  The  height  of  the  head  is  the  distance  from  the  under- 
side of  the  chin  to  the  highest  point  of  the  head.  The  length  of  the 
face  from  the  lower  edge  of  the  chin  to  the  edge  of  the  hair.  The 
length  of  the  foot  is  from  the  back  of  the  heel  to  the  point  of  the 
big  toe  or  second  toe.  The  width  of  the  shoulders  is  to  be  measured 
between  the  contours  of  the  deltoid  muscles,  though  occasionally 
he  indicates  the  '  shoulder-joints  '  as  points  of  measurement. 

The  proportions  of  the  head.  Half  the  length  of  the  head  is 
from  the  crown  to  the  inner  canthus,  from  the  inner  canthus  to 
the  under  edge  of  the  chin,  or  from  the  under  edge  of  the  chin  to 
the  angle  of  the  jaw,  also  from  the  top  of  the  ear  to  the  crown  of 
the  head  ;  the  width  of  the  throat  from  back  to  front  is  also  equal 
to  half  the  height  of  the  head.    The  distance  between  the  mouth 

^  The  quotations  are  given  in  Leonardo's  own  orthography,  which  is  not  always 
consequent  (e.  g.  soto  in  one  place,  sotto  in  the  next). 

N  2 


1S4  LKOXAIIDO    AS    AX  ATOM  IS'I" 

and  the  vib^v  <►!  the  liair,  aiul  Ix'twocii  the  cliiii  and  llic  iia|)C  of 
the  neck  is  thicc-cjiiaitt'rs  tlic  Icii^tli  ot  the  head,  as  is  also  tlic 
•greatest  width  of  tlic  face. 

'V\\o  ptrc  is  diviiU'd  iiilo  (luce  ((jiial  parts,  namely,  from  the 
chin  to  th(^  base  of  the  nose,  from  iiere  to  the  root  of  the  nose, 
'  where  the  eyehrows  begin  ',  and  thence  to  the  comnieneenient 
of  the  hair.  Half  the  length  of  tlie  face  is  from  the  middle  of 
tin*  nose  to  the  chin,  qnarter  from  the  lower  edge  of  the  ehin  to 
the  orifice  of  the  mouth,  from  the  back  of  the  ear  to  the  Jiape, 
from  the  most  |)rominent  ])art  of  the  ehin  to  the  throat.  The 
width  of  the  mouth  is  also  one-quarter  the  length  of  the  face. 
From  the  labio-meutal  furrow  to  the  edge  of  the  hair  is  hve-sixths 
the  length  of  the  face,  one-sixth  from  the  labio-mental  furrow  to 
the  under  side  of  tlie  chin,  one-seventh  from  the  edge  of  the  hair 
to  the  crown,  and  from  the  base  of  the  nose  to  the  orifice  of  the 
mouth,  one-twelfth  of  the  length  of  the  face  from  the  labio-mental 
furrow  to  the  orifice  of  the  mouth  (Plate  xxxvii). 

The  height  and  iV.s-  j^roportions.  The  total  height  equals  eight 
times  the  length  of  the  head.  From  the  edge  of  the  hair  to  the 
ground  is  nine  times  the  length  of  the  face,  three  times  the  distance 
between  the  wrist  and  the  top  of  the  shoulder,  four  times  the 
width  across  the  shoulders,  four  times  the  distance  from  the  centre- 
line of  the  body  to  the  elbow  of  the  stretched  and  abducted  arm. 
Any  of  these  measures  equals  four  ells,  one  ell  (chupido)  being 
the  distance  from  the  elbow  to  the  point  of  the  middle  finger 
with  stretched  arm,  or  the  distance  from  the  point  of  the  elbow 
to  the  point  of  the  thumb  with  bent  arm.  Again,  the  height  may 
be  expressed  as  six  times  the  distance  from  the  hair  edge  to  the 
)nt  of  the  throat,  12  times  the  width  of  the  face,  12  times  the 
distance  from  the  mouth  to  the  edge  of  the  hair,  15  times  the  dia- 
meter of  the  throat  in  profile,  15  times  the  distance  from  the  chin 
to  the  eye,  16  times  the  distance  from  the  point  of  the  chin  to 
the  angle  of  the  jaw,  16  times  the  distance  from  the  chin  to  the 
inner  corner  of  the  eye,  16  times  the  distance  from  the  top  of 
the  ear  to  the  crown,  18  times  from  the  upper  bend  of  the  throat 
to  the  pit  of  the  throat,  42  times  from  the  front  to  the  back  of 
the  arm  at  the  wrist,  and  54  times  the  distance  from  the  labio- 
mental furrow  to  the  underside  of  the  chin. 

If  one  compares  some  of  these  measurements  of  the  body  with 
those  for  proportions  of  the  head,  one  finds  that  the  body  varies 
between  1^  and  sometimes  nine  times  the  length  of  the  head.    . 


LEONARDO  AS  ANATOMIST  185 

By  kneeling,  the  lieiglit  is  lessened  by  a  quarter.  When  in 
this  attitude  the  hands  are  folded  on  the  breast,  the  navel  is  the 
centre-point  and  the  elbows  are  on  a  level  with  the  navel.  In  the 
sitting  posture  the  lower  margin  of  the  shoulder-blades  and  the 
breast  will  be  on  the  same  plane  and  both  at  equal  distances 
from  the  seat,  and  from  the  crown  of  the  head,  while  from  the 
seat  to  the  crown  '  will  be  as  much  more  than  half  of  the  man  as 
tlie  thickness  and  length  of  the  testicles  '.  In  an  upright  position, 
the  aural  orifice,  the  top  of  the  shoulder,  the  great  trochanter,  and 
outer  ankle  bone  will  lie  in  a  line  (Plate  xxxvii). 

The  proportions  of  the  trunk.  The  width  of  the  shoulders  equals 
the  distance  from  the  pit  of  the  throat  to  the  navel,  and  is  twice 
the  height  of  the  head  ;  from  the  navel  to  the  root  of  the  penis 
is  equal  to  the  length  of  the  head.  From  the  nipple  to  the  navel 
is  one  foot,  as  is  also  the  distance  from  wrist  to  elbow,  and  from 
elbow  to  armpit.  The  width  across  the  shoulders  is  equal  to  the 
distance  from  the  great  trochanter  to  the  knee  and  from  here  to 
the  ankle.  The  distance  between  the  arm-pits  is  equal  to  tlie 
width  of  the  hips,  and  to  the  distance  from  the  shoulder-joint  to 
the  top  of  the  hip,  and  from  here  to  the  lower  extremity  of  the 
buttocks.  The  waist  lies  midway  between  the  shoulder-joint  and 
the  lower  extremity  of  the  buttocks. 

The  proportions  of  arm  and  leg.  From  the  point  of  the  longest 
finger  of  the  hand  to  the  shoulder-joint  there  are  four  hands  or, 
if  you  like,  four  heads,  also  three  feet  ;  one  foot  from  the  wrist 
to  the  elbow,  also  from  here  to  the  arm-pit,  and  with  bent  elbow, 
the  distance  from  the  top  of  the  shoulder  to  the  point  of  the 
elbow,  and  from  here  to  the  base  of  the  fingers  both  equal  two 
heads  ;  from  the  finger-points  to  the  arm-pits  is  equal  to  the 
distance  from  the  top  of  the  hip  to  the  knee-cap,  and  from  here  to 
the  sole  of  the  foot,  and  each  of  the  distances  is  two  feet ;  two 
feet  is  also  the  distance  from  the  sole  of  the  foot  to  the  front  of 
the  knee  bent  at  a  right  angle,  and  from  here  to  the  back  part  of 
the  buttocks  ;  the  distance  from  the  great  trochanter  to  the  knee, 
and  from  here  to  the  ankle,  are  equal. 

It  is  probable  that  Leonardo's  study  of  anatomy  first  sprang 
from  his  wish  to  represent  the  surface  anatomy  as  perfectly  as 
])ossible.  In  this  he  carried  out  his  motto  '  to  know  is  to  see  '. 
He  gradually  became  enthralled  by  his  work  of  investigation  and 
so  decided  to  continue  until  he  became  complete  master  of  the 
subject.      His   success   was   achieved   througli    his   intuition,    his 


1S()  LKOXAUDO   AS   ANATOMIST 

power  to  IjiiiidU'  a  variety  of  subjects,  lii.s  tireless  researcli,  and 
his  iiiii)aralleie(l  skill  as  a  (Iraujjjiitsinan.  He  knew  how  to  repro- 
duce as  iu>  saw,  and  lie  saw  perfectly.  On  account  of  his  intimate 
know  led ti;e  of  nearly  every  ])art  of  the  human  frame,  and  of  his 
delicate  and  artistic  treatment  of  them,  his  drawings  acquired 
a  rare  and  hitherto  unsurpassed  beauty.  He  excels  in  his  many 
delineations  of  surface  anatomy,  and  in  them  we  see  portrayed 
a  life  vigorous  in  all  its  many  richly  varied  jihases  and  a  power 
of  observation  that  pierces  all  the  layers  of  the  body.  His  plastic 
colour  drawings  of  the  body  in  different  ])Ositions,  of  whicii 
a  number  on  red-brown  and  blue-grey  paper  appear  in  the  Qua- 
derni,  show  clearly  his  greatness  alike  as  anatomist  and  as  artist. 
Under  the  heading  ^  On  the  human  shape  he  asks,  '  Which  part 
of  the  man  is  it  where  the  flesh  never  increases  when  the  man 
gets  fat,  Which  is  the  part  which,  when  a  man  gets  thin,  never 
becomes  emaciated  with  too  noticeable  an  emaciation  ?  Among 
the  parts  which  become  fat,  which  become  the  fattest  ?  Among  the 
parts  whicli  become  thin,  which  become  most  thin  ?  Among 
those  men  who  are  very  strong,  which  muscles  are  of  greater 
thickness  and  development  ?  '  And  he  continues  under  the 
heading  On  Painting  : 

'  Which  are  the  muscles  which,  in  old  age,  or  in  a  young  person 
who  is  becoming  thin,  separate  ?  Which  are  the  parts  of  the 
human  limbs  where  the  flesh  never  increases  on  account  of  some 
quality  of  the  fat,  and  where  also  the  flesh  never  decreases,  on 
account  of  some  quality  of  the  fat,  and  where  also  the  flesh  never 
decreases  on  account  of  some  degree  of  thinness  ?  What  one 
seeks  in  all  these  questions  mil  be  found  at  all  the  surface  joints, 
as  the  shoulder,  the  elbow,  the  joints  of  the  hands  and  fingers, 
the  hips,  the  knee,  ankles,  and  toes,  and  such  tilings  which  will 
be  discussed  at  their  places.' 

The  following  singular  remark  shows  Leonardo's  speculative 
turn.  He  states  :  that  Nature  has  disposed  in  front  all  the  parts 
most  liable  to  be  bruised,  for  example,  the  brow,  the  nose,  the 
skin.  If  these  parts  were  not  highly  sensitive,  they  would  certainly 
be  destroyed  by  the  man}-  blows  to  which  they  are  exxiosed.- 

Fearless  and  imperious,  zealous  and  grave,  Leonardo  reproaches 
those  who  scorn  the  mathematical  sciences  '  in  which  the  true 
knowledge  of  things  is  contained  ',  those  who  satisfy  themselves 
with  superficial  acquirements,  those  who  deliberately  abbre\date 
authors,  and  those  who  think  they  can  dissect  the  sj^irit  of  God. 
1  Q.  vi,  f.  22  r.  2  151^. 


1.* 


ro 


O      ;i 


■^'^^'i'*^'' 


^-^^^.- 


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o    ;= 


£■7-  1---  -ki. 


LEONARDO  AS  ANATOMIST  187 

He  scorns  sophists  and  despises  human  folly.  He  condemns  those 
who  make  a  god  of  their  stomach,  and  the  betrayers  of  the  weak 
and  innocent.  He  counsels  humility  and  the  recognition  of  genius, 
and  warns  against  persecuting  them  : 

'  And  if  any  one  is  found  to  be  virtuoso  and  good,  do  not  drive 
him  away,  honour  him  so  that  he  will  not  flee  from  you,  and  retire 
to  deserts  or  holes  or  other  sohtary  places  to  escape  your  snares. 
And  if  any  one  of  these  is  found,  honour  liim  for  these,  our 
earthly  gods,  merit  statues,  portraits,  and  marks  of  honour.  But 
I  had  better  remind  you  that  you  must  not  eat  their  portraits, 
as  is  done  in  some  parts  of  India,  where,  when  their  portraits 
perform  some  miracle,  the  priests  cut  them  up  when  they  are 
made  of  wood,  and  give  a  piece  to  each  inhabitant — and  not 
without  compensation  ;  and  each  shaves  his  piece  and  strews  it 
on  the  first  food  he  eats;  and  in  this  way  they  think  they 
have  eaten  his  virtue,  and  believe  that  he  thereafter  protects 
them  from  all  dangers.  What  think  you,  man,  of  your  species, 
here  :  Are  you  as  wise  as  you  think  ?  Are  these  things  which 
ought  to  be  done  by  men  ?  '  ^ 

How  his  steadfast  will  stands  out.  '  Obstacles ',  he  says,  '  do 
not  deter  me  ;  every  obstacle  can  be  overcome  by  resolution.' 
Leonardo  approaches  with  awe  and  reverence  the  anatomical 
problems  he  sets  himself,  but  he  meets  them  with  energy  and 
ardour,  and  it  is  in  the  elucidation  of  these  scientific  difficulties 
that  his  fascinating  personality,  his  creative  imagination,  most 
spontaneously  appear ;  it  is  then  that  one  meets  the  full  force 
of  this  powerful  mind. 

An  illegitimate  child,  disinherited  by  his  father,  hated  by  his 
step-brothers,  and  often  misjudged  by  his  contemporaries,  who 
regarded  him  as  a  mystic  and  one  possessed  of  many  secrets 
which  he  would  not  divulge — he  naturally  felt  forsaken  and 
misunderstood.  He  became  meditative,  and  he  commends  soli- 
tude, for  it  alone  gives  time  for  study.  '  When  you  are  alone, 
you  are  yourself  absolutely  ;  but  if  you  are  attended  by  a  single 
companion,  you  are  only  half  yourself — and  if  you  serve  two 
masters,  giving  yourself  sometimes  to  society,  sometimes  to 
thoughts  of  art — then  I  assure  you  that  in  this  you  will  fail.'  - 

Although  Leonardo  was  without  doubt  the  greatest  naturahst 
of  the  fifteenth  centurj^  and  must  have  realized  the  importance  of 
the  diverse  discoveries  he  made,  yet  he  remained  an  unassuming 
man.     'As  I  see',  he  says  in  a  proeinio,  'that  I  cannot  acquire 

1  Q.  ii.  f.  14  r.  ^  Quoted  from  Siren. 


ISS  J.KONAinX)    AS   ANATOMIST 

iiiiy  moic  iiscliil  Of  inorc  attractive^  matter  tor  study  since  those 
who  have  !i;one  before  nic  have  seeiiic*!  all  that  is  most  useful 
and  necessary,  J  shall  imitates  tlie  man  wlio,  through  poverty, 
went  last  to  the  market,  and  being  iniable  othei'wise  t(j  get  aught 
else,  seized  those  things  thrown  aside  lor  their  worthlessness — 
trivial  and  despised  wares,  the  leavings  of  many  customers.  These 
1  shall  lay  on  my  miserable  pack-ass  and  with  them  wander,  not 
through  the  big  cities,  but  through  tlie  ])oor  villages,  distributing 
them  there  and  earning  a  recompense  in  keeping  with  my  deeds.' ' 
This  attitude  may  also  be  taken  as  an  outcome  of  his  loneliness. 
A  genius,  whose  creative  imj)ulses  never  left  him  any  peace, 
Leonardo  hardly  felt  himself  held  by  any  of  the  common  bonds 
which  force  other  mortals  to  remain  where  they  have  settled 
down.  He  seeks  service  with  various  princes — Ludovico  Moro, 
Caesare  Borgia,  Louis  XI 1,  and  Frangois  I,  wherever  he  thought 
he  might  find  suitable  conditions  for  the  development  of  his  talent 
and  his  plans,  and  for  the  appeasement  of  that  force  wliich  con- 
tinually drove  him  onward,  his  insatiable  desire  to  learn,  to 
understand,  and  to  create. 

Leonardo  seeks,  line  by  line,  to  trace  the  lineaments  of  Nature 
in  all  her  moods.  He  has  the  whole  aLwaj^s  in  view,  regarding 
Nature  as  one.  He  arrives  at  the  conclusion  that  there  is  but 
one  Natural  Law  which  governs  the  whole  world,  and  that  Law 
is  Necessity.  Necessity  is  Nature's  master  and  guardian  ;  it  is 
Necessity  that  makes  the  eternal  laws.'^ 

All  Leonardo's  study  of  Nature,  a  research  which  has  been 
called  a  divine  service — is  visibly  inspired  by  a  great  love  for 
everything  in  Nature,  from  man  to  the  meanest  creature,  and 
fortune  always  follows  his  researches,  w^hether  on  the  Alps  at 
Mombosa^  he  formulates  the  first  scientific  hypothesis  regarding 
glaciers,  or  whether  in  his  study  he  is  examining  the  minute  parts 
of  the  smallest  insect  or  plant. 

'  Great  love  is  born  of  great  knowledge  of  the  objects  one 
loves.  If  you  do  not  understand  them  you  can  only  admire  them 
lamely  or  not  at  all — and  if  you  only  love  them  on  account  of 
the  good  you  expect  from  them,  and  not  because  of  the  sum  of 
their  qualities,  then  you  are  as  the  dog  that  wags  his  tail  to  the 
person  who  gives  him  a  bone.  Love  is  the  daughter  of  knowledge, 
and  love  is  deep  in  the  same  degree  as  the  knoAvledge  is  sure — 
Love  conquers  all  things.'  * 

1  Codice  Atlantico,  f.  119  r.  -  Richter  1135. 

^  Probably  Monte  Rosa.  *  Quoted  from  Siren. 


LEONARDO  AS  ANATOMIST  180 

The  man  who  says :  '  When  J  think  1  have  learned  to  hve, 
(then)  I  will  learn  to  die,'  sees  clearly  the  vanity  of  all  our  desires.' 

'  ]Man  Avho  with  ceaseless  longings  awaits  the  new  fcsti\'e  spring, 
the  new  summer,  coming  months  and  coming  years — man  imagines 
that  all  this  lingers  too  long  on  the  way,  and  does  not  ])erceive 
that  it  awaits  his  own  dissolution.  But',  he  adds,  'this  desire  is 
the  quintessence,  the  true  spirit  of  the  elements  which  feed  them- 
selves through  the  soul,  imprisoned  in  the  human  form  and  is 
always  demanding  to  return — and  I  wish  you  to  understand  that 
this  longing  is  that  quintessence  which  is  nature's  ally,  and  that 
man  is  the  model  for  the  whole  world.' " 

Leonardo's  significance  as  an  anatomist  judged  from  the 
Windsor  manuscripts  can  thus  be  shortly  summed  up:  No  one 
before  him,  so  far  as  is  known,  made  so  many  dissections  on  human 
bodies  nor  did  any  understand  so  well  as  he  how  to  inter]3ret  the 
findings.  His  account  of  the  uterus  was  far  more  accurate  and 
intelligible  than  any  that  preceded  him.  He  was  the  first  to  give 
a  correct  descri]:)tion  of  the  human  skeleton — of  the  thorax,  the 
cranium  and  its  various  pneumatic  cavities,  of  the  bones  of  the 
extremities,  of  the  vertebral  column,  of  the  correct  ])osition  of 
the  pelvis  and  the  corresponding  curvatures  of  the  column.  He 
was  the  first  to  give  a  correct  picture  of  practically  all  the  muscles 
of  the  human  body. 

No  one  before  him  had  drawn  the  nerves  and  the  blood-vessels 
even  approximate^  as  correctly  as  he,  and  in  all  probability  he 
was  the  first  to  utilize  dissections  of  a  solidifying  mass  in  research 
on  the  blood-vessels.  Nobody  before  him  knew  and  depicted 
the  heart  as  Leonardo.  He  was  the  first  to  describe  the  intra- 
ventricular moderator  band.  Whether  and  to  what  extent  he 
understood  the  circulation  of  the  blood  is  still  an  open  question. 

He  was  the  first  to  make  casts  of  the  cerebral  ventricles.  He 
was  the  first  who  employed  serial  sections.  No  one  before  him, 
and  hardly  any  one  since,  has  given  such  a  marvellous  description 
of  the  plastic  surface  anatomy,  nor  had  any  one  before  him 
brought  forward  that  wealth  of  anatomical  details  which  he 
observed,  nor  given  such  correct  information  as  regards  topo- 
graphical and  comparative  anatomy. 

Most  of  Leonardo's  anatomical  and  physiological  drawings 
must  be  said  to  belong  to  the  domain  of  science  rather  than  of 
art.     An  artist  has   no   use  for  any   knowledge  of  the  cerebral 

^  Codice  Atlantiro,  f.  252  r.  -  Quoted  from  Horzfeldt  CXX. 


190  LI^:()\AKDO   AS   ANATOMIST 

ventricles,  of  the  auatoruy  and  pliy.siology  of  tlic  licart,  of  the 
bit  nation  of  tlie  nerves  and  deeper  blood-vessels,  of  the  ramifica- 
tion of  the  hionchi  and  their  relation  to  the  j)ulnionary  vessels. 
The  man  who  takes  interest  in  such  things  and  makes  them  the 
object  of  his  study  and  research  is  surely  a  sclmlist.  It  was  in 
drawing  that  he  found  the  most  satisfactory  medium  for  dealing 
with  such  |)roblems,  and  in  tliese  drawings  he  is  scientist  and 
artist  alike.  He  has  drawn  even  the  most  intimate  anatomical 
details  with  the  accurate  objectivity  of  a  scientist  and  yet  with 
a  virile  sense  of  beauty  which  seems  unparalleled. 

Although  Leonardo  has  not  left  a  complete  and  systematic 
descriptive  anatomy  nor  even  dealt  with  all  its  chapters,  although 
he  has  not  always  given  an  exhaustive  description  of  such  chapters 
as  he  has  dealt  with,  and  although  in  his  descriptions  we  can  trace 
his  dependence  on  old  and  traditional  ideas,  yet  in  the  history  df 
science  Leonardo  will  rank  as  the  first  to  have  illustrated  anatomy 
by  drawings  from  the  object,  the  first  of  the  moderns  to  have  treated 
anatomy  in  a  methodical  and  scientific  way  by  means  of  independent 
research  and  yost-mortem  dissections.  His  singular  form  of  observa- 
tion and  concentration,  his  careful  treatment  of  the  scientific 
problems  before  him,  his  intuitive  powers  and  his  ability  draw 
right  conclusions  and  prove  them  by  experiment,  all  these  resulted 
in  the  many  discoveries  which  he  made  in  human  anatomj"  and 
physiology,  discoveries  that  j^laced  him  centuries  ahead  of  his 
contemporaries  in  kiiowdedge  and  in  thought. 

He  placed  anatomy  in  close  relation  to  physiology,  he  regarded 
the  human  organism  as  well  as  that  of  animals  and  plants  as 
ruled  by  the  general  laws  of  Nature  ;  he  is,  in  short,  a  inodern 
biologist  in  the  disguise  of  a  mediaeval  artist. 

When  we  bear  in  mind  that  Leonardo's  wTitings  and  drawings 
have  shared  the  fate  of  his  pictures — that  most  of  them  have 
been  lost  and  the  remainder  consists  of  fragments  only — when  we 
further  contemplate  what  a  wealth  of  observation,  what  a  sum 
of  natural  science  these  fragments  contain,  w'hen  we  realize  that 
Leonardo  throughout  his  life  was  busied  ^^  ith  numerous  different 
occupations,  then  we  can  only  marvel  at  the  gigantic  energy  and 
genius  that  found  time  for  such  intimate  and  painstaking  anato- 
mical research  of  a  kind  foreign  to  the  ordinary  artist.  No  one 
has  ever,  with  the  same  right  as  Leonardo,  been  able  to  apply 
the  quotation  from  Horace  which  in  a  somewhat  free  translation 


i^^ 


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PLAT  !•:    XXXVII 


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Ouaderni    VI    fo.   8  r 
Proportions  of  trunk 


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jb  ^-twK 


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yuaderni    \' I    fo.   i   r 
Proportions  of  head 


LEONARDO  AS  ANATOMIST  191 

we  find  in  one  of  his  manuscripts,  '  God  sells  us  everything  good 
at  the  price  of  fatigue.'  ^ 

One  may  ask  perhaps  what  do  we  learn  from  Leonardo's 
anatomical  \\Titings  and  drawings  ?  They  can  have  had  no  influ- 
ence on  the  development  of  anatomy,  for  the  fragments  were  not 
collected,  interpreted,  and  published  till  centuries  after  his  death. 
Is  it  not  a  sad  tale  of  labour  lost,  a  tragedy  of  genius  working  in 
vain  without  influencing  the  development  of  science  ?  And  yet 
Leonardo's  anatomical  investigations  have  not  been  altogether 
vain  ;  they  will  for  all  time  stand  out  as  a  proof  of  what  human 
genius  is  capable,  and  Leonardo  will  always  remain  a  glorious 
example  of  an  unconquerable  will,  of  continuous  and  intense 
apphcation  to  work,  of  reverent  self-restraint,  of  love  for  created 
things — a  glorious  example  whose  influence  on  posterity  has  not 
been  lost  with  the  majority  of  his  works.  Truly  he  is  to  be  regarded 
as  a  genius  of  the  highest  order  that  the  world  has  ever  known. 

To  have  had  the  opportunity  to  try  to  track  his  way  of 
reasoning,  the  development  of  his  theories,  his  methods  of 
research,  has  been  a  privilege  which  has  given  more  pleasure 
and  joy  than  one  can  easily  express.  Gratitude  is  the  predominant 
and  overwhelming  sentiment  of  one  who  has  had  the  opportunity 
of  laying  even  a  single  stone  to  the  building  now  being  reared  out 
of  the  remnants  of  the  products  of  one  of  the  world's  greatest 
investigators  and  thinkers,  a  work  of  restoration  which  yet  will 
for  ever  remain  unfinished  since  manj^  of  its  fundamental  stones 
will  be  for  ever  wanting. 

NOTE. — In  the  English  translation  of  the  manuscript  of 
Leonardo's  Quaderni  an  attempt  was  made  to  maintain  some  of 
his  quaint  personal  style  of  writing.  The  quotations  given  above, 
however,  have  not  been  given  the  identical  form  of  that  publication 
but  have  been  altered  into  a  more  readable  English. 

^  Q.  V,  f .  24  r,    Horace,  Satire  ix,  Liber  i,  vers.  59  : 

Nil  sine  maguu 
vita  labore  dedit  mortalibus. 
The  piirase  is  doubtless  derived  from  Epicharmus  in  Xenophon's  Memorabilia, 

'  "     '  Twi'  TTcIi'wv  iro'>\ov(Tiv  jjiJuv  Travra  Taya.6   ot  O^oi. 


^ 


riii:  AscLioiMADAi:  AM)  ini:  immi.sis  of 

AS(  Li:i»n  s 

Hv   K.  '\\   Wri'iiiNc  TON 

In  llic  ancient  history  of  nu'diciiu^  tlicro  an;  two  c))ochs  of 
special  interest :  its  a])parcntly  sudden  a|)|)earanee  as  an  art,  or 
rather  tlie  art  par  excellence,  with  its  miles  and  method  laid  down 
in  the  Hippocratic  treatises  in  the  fifth  century  B.C.,  and  the 
transmission  of  this  Greek  medicine  in  modified  form  to  the  nations 
of  the  west  and  north  in  the  early  Middle  Ages.  The  obscurity 
which  covers  both  processes  temjited  early  historians  to  seize  ui)on 
any  plausible  explanation,  and  they  declared  that  the  first  had 
its  origin  in  the  Asclepieia  or  temples  of  Asclejiius,  and  the  second 
in  the  monasteries  of  St.  Benedict. 

It  was  soon  objected  to  the  former  theory  that  there  is  nothing 
priestly  about  the  Hippocratic  writings,  and  that  no  ancient  author 
ever  calls  Hippocrates  a  priest,  or  represents  any  physician  as 
practising  in  a  temple.  The  controversy  thus  begun  still  continues, 
and  we  are  told  by  two  distinguished  authorities  in  the  same 
Avork  that : 

(1)  '  Born  of  a  family  of  priest  })hysicians,  and  inheriting  all 
its  traditions  and  prejudices,  Hippocrates  Avas  the  first  to  cast 
superstition  aside.  .  .  .  His  training  w^as  not  altogether  bad,  though 
superstition  entered  largely  into  it.  .  .  .  There  is  everj^  reason  to 
believe  that  the  various  *"  asclepia  "  were  very  carefully  conducted 
hospitals,  possessing  a  curious  system  of  ease  books  in  the  form 
of  votive  tablets  left  by  the  patients.  .  .  .  One  of  his  great  merits 
is  that  he  was  the  first  to  dissociate  medicine  from  priestcraft.'  ^ 

(2)  '  The  priests  of  Asclepius  were  not  physicians.  Although 
the  latter  were  often  called  Asclepiads,  this  was  in  the  first  place 
to  indicate  their  real  or  supposed  descent  from  Asclepius,  and  in 
the  second  place  as  a  complimentary  title.  No  medical  Avriting 
of  antiquity  speaks  of  the  Avorship  of  Asclepius  in  such  a  Avay  as 
to  imply  any  connexion  A\dth  the  ordinary  art  of  healing.  The  tAvo 
systems  appear  to  have  existed  side  by  side,  but  to  have  been 
distinct.  .  .  .  The  theory  of  a  development  of  Greek  medicine  from 

^  Art.  '  Hippocrates  ',  Sir  J.  B.  Tuke,  Encyclopaedia  Britannica,  ed.  1911. 


ASCLEPIADAK  ANJ)    PHJESTS   OF  A8CLEPIU8      193 

the  rites  of  Asclepius,  though  defended  by  eminent  names,  must 
be  rejected.'  ^ 

Sixty  years  earUer,  Adams,  the  Britisli  translator  of  Hippo- 
crates, and  his  French  translator,  Daremberg,  were  contradicting 
each  other  in  almost  the  same  terms.  Among  German  authorities 
on  Greek  antiquity,  von  Wilamowitz  opposes  Thraemer,  who, 
though  less  famous  as  a  scholar,  has  written  the  articles  on 
Asclej^ius  in  Roscher's  Lexicon  and  the  Pauly-W issowa  Cyclopaedia 
as  well  as  that  on  Health  Deities  in  the  Cyclopaedia  of  Religion 
and  Ethics,  now  in  progress,  and  continues  a  stubborn  upholder 
of  the  priest-physician  theory.  Finally,  the  great  name  of  Littre, 
always  mentioned  with  reverence  by  students  of  Hippocrates,  must 
be  quoted  on  the  side  of  the  priests,  though  we  may  hope  that 
with  our  present  knowledge  he  would  have  thought  differently. 

It  is  therefore  not  surprising  that,  though  the  priest  party 
were  supposed  to  have  received  a  knock-out  blow  by  the  discovery 
in  1883  of  the  Epidaurus  inscriptions,-  with  their  amazing  mixture 
of  miracles,  dogs,  snakes,  and  bare-faced  quackery,  at  the  head 
centre  of  Asclepius  worEsip,  they  should  have  rapidly  recovered, 
and  that  most  casual  references  to  the  subject  assume  rather  than 
defend  the  priest  theory,  while  a  beautiful  book  by  Dr.  Aravan- 
tinos,^  with  the  prestige  of  being  written  in  Greek,  supports  the 
same  view  with  copiousness  and  ingenuity. 

It  is  not  intended  to  discuss  here  the  v/hole  of  this  wide  and 
intricate  subject,  but  merely  to  contribute  certain  munitions  in 
the  wa}^  of  arguments  (some  perhaps  not  used  hitherto)  to  the 
side  represented  in  the  second  extract. 

The  most  important  quotations  are  : 

(1)  Strabo.  Geography,  xiv.  2.  '  The^^  sa^-  Hippocrates  was 
trained  in  the  knowledge  of  dietetics  by  the  cures  dedicated 
there  '  (the  temple  at  C*os). 

(2)  Pliny,  Natural  History,  xxix.  1.  '  Hippocrates  is  alleged 
to  have  copied  out  the  accounts  wTitten  by  the  patients  cured  in 
the  temple  of  this  god.'  He  proceeds  to  connect  this  with  a  story 
of  the  burning  of  the  temple,  apparently  by  Hippocrates  himself 

^  Art.  '  Medicine,'  Dr.  F.  Payne,  Enc.  Brit.,  ed.  1911. 

2  Ephemeris  Archaeologike,  1883-5.  For  English  translations  see  Hamilton. 
Incubation,  London,  1906,  17  ff.  ;  Withington,  Medical  History,  London,  1894, 
appendix  2. 

^  'AaK\ij7rio<;  kui  ' A(rK\r]Tritiu.      Leipzig,  1907. 


V.H  THE   ASCLEPIADAE  AND 

to  hide  the  sourco  of  his  wisdom.  A  similar  talc  liad  V>ec*n  told 
three  centuries  earlier  by  tlie  physician,  Andreas/  who,  however, 
makes  him  burn  not  the  temple  of  Cos,  but  the  hbrary  of  Cnidus. 

(3)  Fausanias.  Tour,  ii.  27,  says  he  saw  six  pillars  at  E])i- 
daurus  '  inscribed  with  the  names  of  men  and  women  healed  by 
Asclepius,  as  well  as  the  disease  from  whicli  each  suffered,  and 
how  he  was  cured '.  Two  of  these  pillars  were  discovered  in 
1883. 

(4)  Straho,  viii.  6.  '  Epidaurns  is  famous  for  the  manifestation 
(epi])hany)  of  Asclepius  and  he  is  relied  upon  to  heal  all  kinds  of 
disease,  and  has  a  tem})le  there  which  is  always  full  of  patients 
and  dedicated  tablets  on  which  the  cures  are  inscribed  just  as  at 
Cos  and  Tricca.' 

The  first  of  these  is  the  main  argument  for  the  priest  theory. 
Pliny  is  later  and  less  reUable,  and  the  story  of  the  deliberate 
burning  of  the  temple  is  universally  discrechted.  If  good  for 
anything,  it  rather  favours  the  other  side,  for  it  may  indicate 
that  no  '  cures  '  of  scientific  value  were  to  be  found  in  the  existing 
temple,  while  Andreas,  who  by  age  and  profession  was  nearer  to 
the  facts,  may  have  known  that  no  temple  ever  contained  records 
that  could  have  been  of  much  use  to  Hippocrates,  and  so  substituted 
a  library.  But  Strabo  is  a  good  authority,  and  his  statement  was 
accepted  by  Littre,"  who  even  declared  that  the  two  treatises 
known  as  Prorrhetics  I  and  The  Coan  Prenotiones  are  probably 
collections  of  temple  records — an  assertion  frequently  repeated. 

When  a  great  scholar  makes  what  appears  an  amazing  error 
it  is  well  to  get  another  great  scholar  to  point  it  out.  Daremberg 
in  his  translation  of  Hippocrates  not  only  discusses  the  general 
subject,  but  addressing  Littre  on  this  particular  point,  asks,  '  Why 
not  say  also  that  the  Aphorisms  are  derived  from  these  tablets  ; 
except  that,  from  the  little  known  of  the  temple  inscriptions,  the 
supposition  is  still  more  improbable  ?  Strabo  speaks  of  votive 
tablets  at  Epidaurus  describing  treatment.  Now  the  Coan  Pre- 
notiones contain  only  prognostic  statements,  treatment  is  rarely 
mentioned.  They  have,  then,  nothing  to  do  with  Asclepius,  nor 
with  his  priests,  nor  with  the  patients  they  treated  '.^ 

Littre   made  his   assertion  before  editing  the  treatises,   and 

^  Soranus,  Vita  Hip.,  in  Kiilm's  Hippocrates,  iii.  851. 

-  Hippocrates,  i.  48. 

^  CEuvres  choisies  d'Hippocrate,  Paris,  1855,  Introduction,  p.  85. 


THE  PRIESTS   OF  ASCLEPIUS  195 

afterwards  admitted  himself  partly  converted.^    But  his  original 
statement  is  still  repeated  by  adherents  of  the  old  theory,  thougli 
the   treatises   can   now   be   read   in   several   languages,    and   are 
obviously  attempts  to  discover  a  natural  history  of  diseases  and 
their  probable  terminations.    These,  in  a  large  proportion  of  cases, 
are  disastrous — '  they  have  a  painful  death  '  .  ,  .  '  they  are  carried 
off  quickly  '  .  .  .  '  this  symptom  is  pernicious  '  .  .  .  '  that  is  fatal '. 
How  could  this  sort  of  thing   be  derived  from  votive  tablets 
intended  to  encourage  futiu'e  suppUants,  and  advertise  the  grati- 
tude of  the  patients  and  power  of  the  deity  ?    For,  though  there 
were  doubtless  sceptics  in  the  background,  so  far  as  our  records 
go  no  one  (except  possibly  Aristophanes,  the  precise  limit  of  whose 
ridicule  is  hard  to  define)  doubted  the  fact  of  supernatural  inter- 
ference.     It  is  the  god  who  works  every  cure  throughout  the 
thousand  years  of  his  known  activity.    In  the  earlier  period  he  is 
alleged  to  have  cured  most  frequently  by  immediate  miracles, 
later  he  often  prescribed  natural  remedies,  but  the  prescription 
remained  oracular,  and  was  admitted  to  be  so  by  all  writers, 
medical  and  lay.    No  one  is  ever  described  as  going  to  an  Ascle- 
pieion  to  benefit  by  change  of  air,  &c.,  or  for  the  cure  of  a  disease 
obviously  amenable  to  '  the  art ',  any  more  than  a  Cathohc  patient 
goes  to  Lourdes  for  the  sake  of  the  climate,  or  to  get  a  tooth 
stopped.    They  all  hoped,  if  highly  favoured,  to  get  an  immediate 
miraculous  cure,  or,  faihng  that,  supernatural  advice  in  a  dream  ; 
and  unless  we  reject  a  vast  amount  of  evidence,  they  nearly 
always  got  the  dream,  and  sornetimes  the  instantaneous  cure. 

It  seems  improbable  that  any  one  should  even  begin  to  study 
the  natural  course  of  disease,  the  great  object  of  Hippocratic 
medicine,  in  conditions  where  supernatural  intervention  was  con- 
tinually expected. 

We  may  add  a  subsidiary  argument  which  seems  to  have 
escaped  notice.  The  34th  Prorrhetic  says,  '  Muttering  delirium 
with  trembhng  of  the  hands  and  carphology  are  strong  indications 
of  phrenitis,  as  with  Didymarchus  in  Cos  '.  Strangely  enough, 
though  many  locaUties  are  mentioned  in  the  Hippocratic  Collec- 
tion, this  is  the  only  patient  said  to  have  been  treated  '  in  Cos  '. 
But  if  these  are  the  records  of  the  local  Asclepieion,  they  were 
obviously  all  treated  there,  and  the  remark  is  quite  uncalled  for. 
Further,  a  large  proportion  of  the  patients  evidently  suffered  from 

^  Op.  cit.  viii.  628. 


196  'I'lIK    ASCLKIMADAK   AND 

vcrv  acute  disease,   hut    our  reeords  (tiw  liardly  a  siiifrlc  case  of 
iv  patieut  eaiiied  to  a  teiu|)le  ;    tluy  could  almost  all  walk. 

Distuihed  l)y  the  discovery  of  the  pillars  at  I'^pidaurus,  hiter 
uphohlers  of  the  Straho-Littre  view  attempt  to  distinji;uish  hctweeu 
j)illais  and  tahlets  in  (pialitv  as  well  as  size.  'I'licy  even  .suggest 
that  the  tahlets  were  hke  our  hos])ital  ciiarts  j)ut  at  the  head  of 
the  patient's  bed,  with  a  diagnosis  of  the  disease  and  daily 
remarks  ;  '  hut  this  is  inconsistent  both  with  the  words  of  8trabo 
and  all  else  we  know  of  the  ta})lets.  The  first  case  on  the  ])illars 
is  that  of  (*leo,  who  was  safely  delivered  of  a  five  years'  })oy, 
'  and  hi*  promptly  washed  himself  and  walked  about  with  his 
mother.  Now  when  this  had  happened  to  her,  she  wrote  on 
a  votive  tablet, 

'-  Marvel  not  at  the  size  of  this  tablet  but  at  the  occurrence, 
Five  years  Cleo  was  pregnant  ;    she  ii\e\)t  and  the  god  made 
her  whole  ".' 

This  lady  evidently  did  things  on  a  large  scale,  but  even  her 
tablet  only  contained  a  coui)let.  There  is  no  reason  to  suppose 
that  those  of  others  contained  more  than  a  brief  mention  of  how 
they  were  cured  by  the  god,  and  when,  in  the  late  Roman  period, 
we  meet  with  something  like  a  clinical  history  in  the  record  of 
M.  J.  Apellas,-  it  requires  much  more  than  a  tablet. 

Still,  there  must  be  some  explanation  of  Strabo's  statement, 
and  the  following  suggestion,  though  novel,  may  be  worth  notice. 
The  four  books  '  On  Diet ',  ascribed  to  Hippocrates,  end  with  the 
statement  that  the  author  has  investigated  the  rules  of  diet  as 
well  as  he  could  '  with  the  help  of  the  gods  '.  This  common 
phrase  occurs  nowhere  else  in  the  Collection.  It  would  therefore 
be  noticeable,  and  might  have  been  used  by  votaries  of  super- 
natural as  opposed  to  secular  treatment  somewhat  in  this  wsbV : 
'  Hippocrates  himself  admits  he  got  his  knowledge  of  dietetics  by 
the  aid  of  the  gods.  He  must  evidently  have  meant  Asclepius 
in  particular,  and  how  could  he  learn  his  treatment  except  from 
the  temple  cures  ?  ' 

Here  is  a  possible  origin  for  Strabo's  '  They  say ' — which  is 
after  all  a  qualification,  while  his  statement  that  there  was  no 
difference  between  the  tablets  at  Epidaurus  and  those  at  Cos, 
which  the  priest  party  now  tries  to  distinguish,  is  categorical. 

1   Aravantinos,  op.  cif..  p.  164.  ^  See  the  Epidaurus  inscriptions. 


THE  PRIESTS   OF  ASCLEPIUS  197 

To  pass  to  wider  questions  :  when  we  try  to  find  dates  for 
the  definite  establishment  of  the  therapeutic  dream  oracle  they 
strike  us  as  unexpectedly  recent.  Getting  advice  in  dreams  is, 
of  course,  as  old  as  mankind.  Some  anthropologist  has  said  that 
when  primitive  man  was  in  a  difficulty  he  first  asked  advice  of 
his  friends  ;  if  they  were  no  good  he  went  to  the  old  men,  and 
if  they  failed  him,  to  those  still  older,  the  dead.  He  slept  on 
the  tomb  of  his  ancestors  and  got  advice  in  a  dream,  as  Herodotus 
tells  us  was  the  custom  of  certain  Africans.  But  for  incubation 
in  Asclepieia  the  oldest  definite  date  is  420  B.C.,  when  the  worship 
of  the  god  was  established  at  Athens,  and  his  method  of  cure 
received  with  ridicule  by  the  sturdy  conservative  Aristophanes. 
This,  no  doubt,  shows  that  the  custom  had  been  long  in  use,  and 
there  is  one  example  of  possibly  earlier  date  in  a  fragment  of 
Hippys  of  Rhegium,  who  is  supposed  to  have  flourished  '  during 
the  Persian  wars  ',  about  480  b.  c.  This  case  also  occurs  on  the 
pillars,  which  were  set  up  two  centuries  later,  but  the  following 
is  the  Hippys  version  : 

'  A  woman  had  a  worm,  and  the  ablest  physicians  gave  up 
curing  her.  So  she  went  to  Epidaurus  and  besought  the  god  for 
deliverance  from  the  domestic  plague.  The  god  was  not  there, 
but  the  attendants  made  the  patient  lie  down  where  the  god  is 
wont  to  heal  the  suppliants,  and  she  went  to  rest  as  directed. 
But  they,  in  the  absence  of  the  god,  began  her  treatment  and  cut 
off  her  head.  Then  another  put  his  hand  down  and  took  out  the 
worm,  a  great  thing  of  a  beast,  but  they  were  no  longer  able  to 
put  the  head  back  and  fit  it  accurately  to  the  old  joining.  Then 
the  god  came,  and  was  angry  with  them  for  undertaking  a  task 
beyond  their  wisdom,  but  he  himself  by  power  invincible  and 
divine  put  the  head  back  on  the  trunk,  and  raised  up  the  guest.' ' 

On  the  pillars  the  story  is  told  with  variations  and  additions. 
The  woman  was  Aristagora  of  Troizen,  and  she  incubated  there,  but 
Asclepius  was  at  Epidaurus  and  had  to  be  sent  for — a  hint  that  if 
one  wants  prompt  supernatural  aid,  Epidaurus  is  the  place. 

Admitting  the  date  of  Hippys,  this  story  not  only  shows  the 
existence  of  lay  physicians  before  Hippocrates,  of  which  we  have 
ample  proof,  but  also  indicates  a  clear  distinction  acknowledged 
to  exist  between  human  medicine  and  the  supernatural  aid  of  the 
Asclepieia. 

It  is*  fair  to  add  that  Dr.  Aravantinos  sees  in  this  case 
a  pretended  tracheotomy  by  medical  student    deacons.      Then 

1  Aelian,  H.A.  ix.  33. 

2391  jj 


198  THE   ASCI.EPIADAK   AND 

enters  tlie  |»ii('s1  |»livsi(iitii  iiiid  iuiniiniKtcrH  a  strong  emetic  or 
vermifuge.  In  tlie  pillar  versioji  Aselepius  extrac:ts  the  worm 
after  gastrotomy.  The  ])atient  meanwhile  is  under  narcosis  from 
maiuhagora,  or  the  hke,  and  dreams  of  decapitation  followed  by 
gastric  disturbance,  llcr  story,  though  not  accurate,  was  con- 
sidered edifying,  and  was  |)ublished  accordingly.  The  priest 
physicians  kept  their  real  treatment  secret  and  performed  sham 
superficial  operations  to  mislead  and  increase  the  wonder  of  the 
public'  There  is  something  to  be  said  for  this,  but  its  bearing 
on  our  present  ])roblem  lies  in  the  apj)lication. 

Apart  from  the  above,  Greek  literature  of  the  fifth  century 
has  nothing  to  say  about  the  thera])eutic  dream  oracle.  It  is 
perhaps  not  strange  that  Athenian  writers  should  ignore  it,  and 
we  may  notice  that  they  always  speak  of  medicine  as  a  secular 
art.  Thucydides,  describing  the  plague  at  Athens,'^  contrasts  the 
human  art  of  medicine  with  prayers,  divinations,  and  the  like, 
saying  that  they  were  equally  useless.  Sophocles,  in  the  famous 
ode  in  the  Antigone,^  puts  the  healing  of  diseases  among  the 
things  achieved  by  unaided  man.  Even  Aeschylus  classes  medicine 
with  agriculture  and  navigation  as  a  natural  art,  and  if  he  gives 
it  a  demigod  as  founder,  he  is  not  Asclepius  but  Prometheus  ^ — 
a  myth  which  the  Hippocratics  with  their  emphasis  on  prognosis 
would  have  readily  explained. 

But  the  silence  of  Herodotus  is  remarkable.  He  came  from 
the  immediate  neighbourhood  of  Cos,  from  a  Dorian  colony  founded 
by  Troizen,  as  was  Cos  by  Epidaurus,  though,  like  the  Hippocratic 
Asclepiadae,  he  wTites  in  Ionic.  He  was  interested  in  medicine, 
giving  us  vivid  glimpses  of  certain  physicians  and  mentioning 
medical  schools,  as  to  which  it  is  noteworthy  that  while  the  oldest 
Asclepieia  are  all  in  Greece  proper,  the  oldest  medical  schools  are 
all  outside.^  He  was  still  more  interested  in  the  gods  and  their 
strange  oracles  ;  yet  he  has  no  word  of  Asclepius  or  the  great 
therapeutic  oracle  supposed  to  exist  close  to  him  and  to  be  a  main 
source  of  the  medicine  of  the  age  ;  and  that  though  he  mentions 
other  dream  oracles  both  among  Greeks  and  barbarians. 

1  Op.  cit.,  p.  118.  2  ii  47  3  Lijie  354  4  p^^m.  460,  484. 

5  There  is,  perhaps,  as  much  to  be  said  for  the  suggestion  that  the  prominence 
of  the  dream  oracle  in  Greece  proper  hindered  the  development  of  medical  schools 
there  as  for  the  theory  that  it  gave  origin  to  the  actual  schools  of  Cos,  Cnidus, 
Rhodes,  Cyrene,  and  Croton. 


THE  PRIESTS   OF  ASCLEPIUS  109 

Most  amazing  is  the  silence  of  the  Hippocratic  writers  them- 
selves. Omitting  the  late  and  spurious  '  Letters  ',  the  collection 
contains  literally  one  word  on  the  subjedt ;  the  name,  Asclepius, 
coming  after  Apollo  in  the  Oath.  And  even  the  Oath  gives  some 
evidence  against  the  priest  theory,  for  it  is  taken  by  visiting 
practitioners.  '  Into  whatever  houses  I  enter  I  will  go  for  the 
good  of  the  patients.'  These  Asclepiadae  are  great  travellers 
(7r€/otoSevraO>  and  if  they  settle  anywhere  they  practise  not  in 
a  temple  but  a  surgery  (tarpetoi/),  concerning  which  there  is 
a  special  treatise.  There  are  also  two  works  of  great  antiquity 
and  excellence  On  the  Art  and  On  Ancient  Medicine  deahng  with 
its  nature  and  history.  Here  surely  we  might  expect  something 
about  Asclepius,  his  priests  and  his  temples,  but  there  is  nothing, 
nor  do  the  writers  show  the  least  consciousness  that  the  Art  is 
being,  or  has  been,  freed  from  superstition. 

This  Art  makes  no  claim  to  supernatural  aids  or  inspired 
knowledge,  but  '  clearly  has  and  ever  will  have  its  essence  in 
causation  and  the  power  of  foretelling  '.  In  other  words,  relying 
on  the  uniformity  of  causal  sequence  in  nature  we  can,  from 
observation  of  like  cases,  foretell  the  probable  sequence  of  events 
in  diseases,  and  the  modifications  which  may  be  produced  by 
changes  in  diet  and  other  agencies.^ 

The  author  of  Ancient  Medicine,  perhaps  Hippocrates  himself, 
also  makes  diet  the  main  source  of  the  art,  but  knows  nothing 
of  temple  cures.  It  was  observed  of  old,  he  says,  that  if  healthy 
men  ate  the  coarse  uncooked  food  of  animals  they  were  taken 
ill,  and,  similarly,  if  the  sick  followed  the  diet  of  the  healthy 
they  became  worse,  and  combining  these  observations  with  reason 
men  proceeded  to  establish  by  experiment  the  rules  of  dietetics. 
This  he  calls  a  great  invention  elaborated  and  perfected  with  no 
mean  display  of  intelligence  and  observation.^ 

The  healing  art,  he  adds,  '  possesses  all  things  from  of  old, 
a  principle  and  a  beaten  track  along  which  in  the  course  of  ages 
many  splendid  discoveries  have  been  made,  and  along  which  the 
rest  will  be  discovered,  if  competent  men,  knowing  the  things 
already  discovered,  set  out  thence  on  further  inquiries.  He  who, 
rejecting  these,  takes  another  road  and  claims  to  have  discovered 
something  is  deceived  and  deceives  himself,  for  it  is  impossible  '.^ 

This  idea  that  the  method  of  medical  progress  by  observation 

1  De  Arte,  §  6,  Littre,  vi.  10.         ^  §  ^  Littre,  i.  580.  ^  §  2,  Littre,  i.  572. 

0  2 


2(M)  THK   ASC^LEPJADAE  AND 

aii(i  reason  lias  lon^  been  cstahliKlied  is  n^pcated  cleewhore/  and 
though  '  (harms,  auudot.s,  and  other  sucli  vulgarity  '  may  be  used 
by  some,  there  in  no  .suggestion  that  true  votaries  of  the  art  have 
ever  been  deluded  by  these  or  other  suyx^rstitions.  Wliat  is 
objected  to  is  not  priestcraft,  but  theorizing  [)hilosophy. 

The  Ancient  Medicine  contains  the  one  intimation  that  the 
art  was  thought  worthy  to  })e  ascribed  to  a  god.^  We  look  out 
hopefully  for  Asclepius,  but  the  writer  tells  us  instead  that  this 
saying  is  justified  because  medical  discovery  depends  on  the 
application  of  reason  to  the  nature  of  man. 

Physicians  are  called  hrjixLovpyoif^  '  practisers  of  a  public  art ' 
as  in  Homer,*  and  Plato,  our  best  authority  on  Hippocrates, 
classes  the  physician  with  Pheidias  and  Polyclitus  as  an  '  artist '. 
If  you  pay  any  of  these  men  money  they  will  teach  you  their 
art,  medicine,  or  sculpture/  Similarly,  Socrates  is  made  to  draw^ 
his  comparisons  with  about  equal  frequency  from  the  arts  of  the 
cobbler,  the  pilot,  and  the  physician. 

The  Collection  also  contains  a  treatise  On  Dreams.^  Certain 
diviners  are  said  to  be  skilled  in  predicting  from  dreams  things 
about  to  happen  to  cities  and  individuals,  but  when  they  try  to 
interpret  dreams  foreboding  bodily  affections  they  get  hopelessly 
muddled  owing  to  their  ignorance  of  physiology.  The  writer  then 
makes  a  laudable  attempt  at  a  naturahstic  theory  of  dreams, 
connecting  them  with  bodily  states,  but  there  is  not  a  word  about 
therapeutic  dreams.  Various  gods  are  mentioned  who  may  be 
prayed  to  for  preservation  of  health  and  prevention  of  disease, 
but  Asclepius  is  not  among  them. 

Diviners  come  off  badly  in  these  treatises.  Ignorant  physicians 
who  quarrel  with  one  another  and  give  contradictory  advice  are 
said  to  bring  scandal  on  the  art,  '  and  almost  make  it  resemble 
the  art  of  divination,  for  this  is  how  diviners  act  '.^  Another 
treatise  holds  up  to  reprobation  certain  '  cheating  diviners  '  who 
persuade  young  women  recovered  from  hysteric  affections  to 
dedicate  their  best  dresses  '  and  many  other  things  '  to  Artemis, 
and  liints  that  they  would  be  better  used  to  get  married  in.^ 

The  forty-two  plinical  histories  of  the  '  genuine  '  Hippocrates 

1  Littre,  vi.  342  ;   Loc.  Horn.,  §  46.  ^  §  14   Littre,  i.  600. 

3  §  1,  Littre,  i.  570.  *  Od.  xvii.  384.  ^  Protagoras,  311  b. 

«  Littre,  vi.  640.  '  Littre,  ii.  242,  3Iorh.  Acut.  3. 

8  Littre,  viii.  468,  Morb.  Virg.  1. 


THE  PRIESTS  OF  ASCLEPIUS  201 

correspond  in  number  with  the  forty-two  '  Cures  of  Apollo  and 
Asclepius  '  on  the  pillars,  but  in  everything  else  it  is  impossible 
to  imagine  a  greater  contrast.  Most  of  the  Hippocratic  cases  end 
fatally,  and  the  treatment  of  those  who  recover  is  rarely  con- 
sidered worth  mention.  The  temple  cures  are  instantaneous  or 
nearly  so  ;  '  when  day  appeared  he  went  away  healed  '  is  the 
usual  ending,  the  few  instances  of  delay  being  due  to  want  of 
faith  or  over  hastiness  of  the  attendants,  as  with  Arist agora. 

To  sum  up :  if  there  was  a  therapeutic  dream  oracle  at  Cos 
in  the  fifth  century,  the  Hippocratic  writers  will  have  nothing  to 
do  with  it,  they  will  not  even  mention  it.  As  von  Wilamowitz 
says,  '  The  Epidaurian  colonists  carried  Asclepius  with  them  to 
Cos,  but  not  medicine.  Where  medicine  is  concerned  '  the  god 
disappears.  Instead  of  the  priest  comes  the  physician  ;  instead 
of  the  dream  oracle,  science  ;  instead  of  Asclepius  the  Asclepiad  '.^ 

A  partial  explanation  of  this  remarkable  silence  may  be  found 
in  the  practical  certainty  that  the  Asclepiadae  were  not  only  not 
priests  but  not  Dorians.  Our  earliest  information  about  them  is 
a  chapter-heading  from  Theopompus.  '  Concerning  the  physicians 
in  Cos  and  Cnidus,  how  they  are  called  Asclepiadae,  and  how  they 
first  came  from  Syrnus  ',  a  town  in  Caria.  They  came,  then,  from 
the  East,  not  West,  and  belonged  to  an  older  stratum  of  Greek 
emigrants.  They  wrote  in  a  dialect  more  Homeric  than  Doric, 
and  held  the  Homeric  view  of  Asclepius,  that  he  was  a  mere  man, 
the  founder  of  their  guild  and  ancestor  of  its  more  prominent 
members.  They  were,  perhaps,  astonished  by  the  appearance  of 
their  patron  as  a  Dorian  earth-god  followed  by  mystic  snakes ; 
and  though  they  may  soon  have  established  a  modus  vivendi  with 
the  invaders,  a  difference  of  view  as  to  Asclepius  remained  per- 
manent, for  both  Galen  ^  and  Pausanias  ^  tell  us  that  it  was 
disputed  even  in  their  time  whether  Asclepius  was  a  deified  man 
or  '  a  god  from  the  beginning  '. 

There  is  evidence  of  this  difference  at  Cos.  The  temple  certainly 
acknowledged  the  primacy  of  Epidaurus,  whence  it  got  its  snakes, 
but,  according  to  another  story,  it  was  founded  direct  from  Tricca, 
the  home  of  the  Homeric  and  purely  human  Asclepius.  A  deified 
hero  might  appear  and  give  advice  at  his  tomb,  as  did  Amphiaraus, 
but  an  epiphany  of  Asclepius,  like  that  of  the  high  gods,  might 

1  Isyllos  von  Epidaurus,  Berlm,  1886,  pp.  37  and  103. 

2  i.  22.  Kiihn's  edit.,  Protrept.  9.  Mi.  26. 


202  TKE  AS(  LEPIADAE   AND 

occui-  aii\  wlioro,  for  he  was  also  an  rrnf)o(lim(Mit  of  tlio  <irvn,t 
carth-spiiit  in  his  capacity  of  couiisc^llor  and  licalcr.  I'ossihly 
tluTc  was  first  a  sinipk^  sliriiic  at  ('os,  where  the  Asclepia(la(3 
celebratiMi  th«"  iiicniorv  of  their  patron  but  did  not  expect  liim 
to  a.p|)eai"  ;  while  the  dream  oracle  and  the  snakes  came  later 
trom  Kpi<laurus,  and  were  for  a  time  deliberately  ignored  by  tlie 
medical  school. 

So  much  for  the  silence  of  Hippocrates,  or  rather,  of  the 
Ascle|)iadae,  the  importance  of  which  as  regards  our  ])roblem, 
es|)ecially  when  combined  with  what  they  do  say,  has  perhaps 
been  overlooked. 

Neither  Celsus  nor  the  autlior  of  the  brief  outline  of  medicaf 
history  in  the  Introduction,  formerly  ascribed  to  Galen,^  men- 
tion priest-|)hysicians,  and  the  former  tells  us  that  Hiy)pocrates 
separated  medicine  from  philosophy. 

For  the  bearing  on  the  question  of  inscriptions  concerning 
medical  men  and  priests  the  reader  should  refer  to  the  work  of 
Pohl  [De  Graecorum  medicis  jmblicis,  Berlin,  1905),  where  full 
references  are  given.  The  writer  sums  up  his  conclusion  thus  : 
'  In  the  latest  age,  then,  the  true  art  of  medicine  and  that  of  the 
priests  of  Asclepius  got  mixed,  after  arising  from  widely  separated 
sources  and  continuing  a  long  time  distinct.' 

The  slight  modification  we  would  make  in  this  statement  may 
be  illustrated  from "  another  point  of  view,  not  yet  sufficiently 
studied,  the  attitude  of  later  medical  writers  towards  the  oracle. 

We  have  seen  that  the  earlier  ignore  it,  and  our  first  available 
reference  is  from  Rufus  of  Ephesus,  called  by  Oribasius  '  the 
Great ',  whose  fragments  reveal  a  man  of  much  ability  and  sober- 
mindedness. 

A  certain  Teucer,  afflicted  with  epilepsy,  went  to  the  Ascle- 
pieion  at  Pergamus  and  besought  the  god  to  heal  him.  Asclepius 
appeared,  as  usual,  in  a  dream,  and  asked  whether  he  would  like 
another  disease  instead.  Teucer  replied,  this  was  not  his  most 
earnest  desire,  in  fact  he  would  rather  be  healed  entirely  ;  but  if 
that  was  impossible,  and  the  other  disease  less  troublesome,  he 
would  accept  it.  The  god  replied  that  it  was  less  troublesome, 
and  was  also  the  best  cure  for  his  complaint.  Thereupon  he  was 
attacked  by  a  quartan  fever,  but  was  delivered  from  his  epilepsy.^ 

^  xiv.  674.  Introductio  seu  Medicus.  > 

2  Oriba^jiui?,  xlv.  30,  Daremberg's  edition,  iv.  86,  Paris,  1862. 


THE  PRIESTS  OF  ASCLEPIUS  203 

This  is  told  in  illustration  of  the  Hippocratic  Aphorisms  that 
fevers  generally,^  and  quartans  in  particular,-  relieve  spasms, 
a  principle  which,  according  to  Rufus,  had  been  successfully 
utilized  in  medicine. 

We  pass  to  Galen  with  great  expectations,  for  he  was  a  native 
of  Pergamus.  He  calls  Asclepius  his  ancestral  god  (though  he 
was  not  an  Asclepiad),  and  tells  us  he  saved  his  life  at  least  once 
by  curing  a  disease,  and  perhaps  again  by  warning  him  not  to 
go  with  Marcus  Aurelius  to  the  Danube.  He  therefore  became 
a  special  OepanevTrj^  or  votary  of  the  god.  Yet  the  vast  bulk  of 
his  extant  works  affords  us  only  four  or  five  cases,  including  his 
own.  This,  he  says,  was  '  a  pernicious  abscQss  \'''  but  he  describes 
it  elsewhere  as  a  chronic  pain  between  the  liver  and  diaphragm.* 
He  was  then  a  young  man  and  thought  he  was  going  to  die,  but 
Asclepius  in  a  dream  recommended  bleeding  from  an  artery  and 
he  rapidly  recovered.  The  god  ordered  the  same  treatment  in 
the  case  of  another  '  votary  '  with  a  chronic  pain  in  his  side,  and 
it  was  partly  owing  to  these  '  cures  '  that  Galen  became  convinced 
of  the  value  and  safety  of  arteriotomy,  of  which  he  previously 
had  doubts. 

A  third  case  is  that  of  the  corpulent  Nicomachus,^  whose 
treatment  unfortunately  is  not  given,  but  may  be  connected  with 
a  remark  made  elsewhere  that  patients  will  obey  the  directions 
of  Asclepius  even  to  the  extent  of  going  entirely  without  drink 
for  fifteen  days,  which  they  would  never  do  on  the  orders  of 
physicians,^ 

A  fourth  cure  is  that  of  '  elephas  ',  supposed  to  be  leprosy.^ 
Here  the  patient  was  summoned  by  the  god  from  Thrace  to 
Pergamus,  and  the  treatment  ordered  was  the  internal  use  of 
theriac,  a  famous  medicine  containing  viper's  flesh,  combined  with 
viper' s-flesh  ointment.  The  disease  was  thereby  converted  into 
'  lepra  ',  which  was  cured  '  by  drugs  ordered  by  the  god  '.  Accord- 
ing to  Galen,  the  treatment  of  elephas  by  viper's  flesh  had  been 
discovered  accidentally  some  time  before,  and  had  been  success- 
fully used  by  himself.  There  is  also  evidence  that  it  had  been 
employed  by  Archigenes  half  a  century  earlier  (Aetius,  xiii.  121). 

1  iv.  57,  Littre,  4,  522.  2  y   70,  Littre,  562. 

^  xix.  19,  Kiihn.s  edition,  Libr.  Propr.,  2.  *  xi.  314  ff.,  Venesect.  23. 

5  vi.  869,  Dif.  Morb.  9.  «  xvii6.  137,  In  Hipp.  Epid.  vi.  4,  8. 

'  xii,  315,  Sim  pi.  Med.  xi.  1. 


■204  THE   A8(:LEP]AI)AE   AND 

Filially,  ^v('  iiavo  arecoriuncndatioji  in  adicam  of  a  local  a])|»lit'atioji 
for  Hwolloii  tongue,  confirming  Calcn's  advice  against  that  of  other 
phyKicianH,  but  this  is  not  clearly  attributed  to  Asclepius.' 

In  these  cases  th(5  treatment,  so  far  as  known,  contains  an 
element  of  recognized  medicine,  but  the  theurgic  side  remains 
prominent.  It  is  the  god  who  cures,  and  the  patients  attribute 
their  recovery  to  his  supernatural  interference.  So,  too,  Rufus 
and  Galen,  as  will  be  clearer  to  those  who  look  up  the  context, 
show  not  the  slightest  doubt  of  the  supernatural  (character  of  the 
intervention.  They  may  point  out  the  medicinal  nature  of  the 
means,  and  some  circumstances  which  favour  success,  but  the 
cure  is  essentially  divine  even  when  it  gives  divine  sanction  to 
human  methods.  There  is  no  true  mixture  :  the  '  Cures  '  of 
Asclepius  are  separated  to  the  last  from  those  of  the  art  by 
a  strong  element  of  miracle  :  they  are  two  distinct  things,  and 
medical  writers  show  no  consciousness  that  they  ever  had  been, 
or  were  tending  to  become,  the  same.  The  latest  recorded  temple 
cure  is  as  purely  miraculous  as  the  earliest,  though  in  a  different 
way. 

Archiadas  of  Athens  had  a  daughter  afflicted  by  a  painful  and 
incurable  disease.  So  he  besought  Proclus  the  philosopher  to 
intercede  with  Asclepius  for  her  cure.  Proclus,  whose  benevolence 
equalled  his  wisdom,  at  once  went  to  the  Asclepieion,  '  fortunately 
not  yet  plundered  ',  and  prayed  according  to  the  ancient  rites. 
The  patient  felt  a  sudden  change  in  her  condition  and  great  relief, 
and  when  the  philosopher,  having  ended  his  petitions,  came  to 
see  the  effect,  he  found  her  '  delivered  from  her  pains  and  in 
perfect  health  '.    This  was  in  the  latter  part  of  the  fifth  century.^ 

The  closing  of  the  Asclepieia  was  followed  almost  immediately, 
or  even  preceded,  by  the  establishment  of  dream  oracles  in 
Christian  shrines,  especially  that  of  SS.  Cyrus  and  John  at 
Alexandria.  Seventy  of  their  cures  are  recorded  by  Sophronius, 
Patriarch  of  Jerusalem  (d.  640),  who  had  himself  been  healed 
by  them.  They  closely  resemble  those  of  Asclepius,  the  chief 
difference  being  that  the  saints  are  represented  as  indignant  at 
any  suggestion  that  their  cures  are  not  miraculous  throughout, 

1  X.  971,  Meth.  Med.  xiv.  9. 

2  Marinus,  Vita  Prodi.  For  translation  see  Taylor,  Proclns,  London,  1788, 
i.  26.  The  god  also  appeared  to  Proclus  on  his  deathbed,  "  and  Avould  probably 
have  cured  him  had  he  desired  it,'  op.  cit.  i.  27. 


THE  PRIESTS  OF  ASCLEPIUS  205 

and  inflict  severe  punishment  on  a  rash  physician  who  declared 
that  some  of  their  prescriptions  might  be  found  in  Galen  and 
Hippocrates}  In  fact  secular  and  sacred  medicine  are  in  open 
opposition. 

To  return  to  the  fifth  century  B.C.  and  the  origin  of  Hippo- 
cratic  medicine.  While  not  professing  to  solve  that  obscure  and 
interesting  problem,  it  is  hoped  that  some  additional  reasons  for 
rejecting  the  superficial  view  that  '  it  originated  in  the  health 
temples  '  are  given  in  these  notes.  What  can  be  said  in  favour 
of  that  view  may  be  found  in  the  works  noticed  at  the  beginning. 
It  may  seem  to  some  that  the  arguments  there  adduced  do  not 
outweigh  the  single  fact  (the  most  certain  in  medical  history)  that 
in  the  fifth  century  B.  c.  medicine  was  known  throughout  Greece 
as  an  art,  the  chief  of  arts,  too  long  to  be  learnt  in  this  short  hfe. 
For  arts  are  not  learnt  in  temples  by  observing  real  or  supposed 
supernatural  intervention,  but,  as  the  Hippocratic  writers  tell  us, 
by  experience  and  the  apphcation  of  reason  to  the  natures  of  men 
and  things. 

^  Mai,  Spicilegium,  vol.  iii,  case  30,  Rome,  1840. 


V) 

V 


THE   SCIENTIFIC    WORKS    OF   CALILEO 
(15(>4— 1642) 

WITH  SOME  ACCOUNT  OF  HIS  LIFE  AND  TRIAL 

Being  a  Review  of  Favaro's  Kdizione  nazionale  delle  Opere  di 
(r'a/i7eo  (1890-1909) 

Bv  J.  J.  Fahie 

PAGE   I  PAGE 

I.  The    Galileiaii    Researches    of           i  III.  Life  Work  (1593-1632)      .      .   217 

Antonio  Favaro    ....   206  j    ly.  The     Trial     and    Abjuration 

II.   Early     Manhood     ot     Galileo  |  (1633) 257 

(1564-92) 207  I     V.  Declining  Years  (1634-42)      .   272 

1.    The  Galileian  Researches  of  Antonio  Favaro 

In  the  current  year  1920,  Professor  Antonio  Favaro,  of  Padua 
University,  completes  forty-four  years  ^f  Galileian  studies.  The 
result  is  monumental ;  besides  editing  the  National  Edition  of 
Galileo's  Works  in  twenty  large  quarto  volumes,  Favaro  has 
published  over  450  separate  studies  on  matters  relating  to  the 
life,  times,  and  activities  of  the  great  master.  The  vastness  of  the 
labour  involved  in  this  kind  of  literary  work  can  be  appreciated  only 
by  those  who  have  themselves  engaged  in  historical  researches. 

Antonio  Favaro  was  born  on  the  21st  of  May,  1847,  in  the 
Villa  Favaro  at  Fiesso  d'Artico,  on  the  Brenta,  and  about  half-way 
between  Padua  and  Fusina.  He  was  educated  at  the  L'niversities 
of  Padua,  Turin,  and  Ziirich,  and,  after  a  few  years  of  private 
teaching,  was  elected  in  1872  to  the  newly  created  chair  of 
Graphical  Statics  in  the  University  of  Padua,  being  then  only 
twenty-five  years  of  age.  A  few  years  later  he  was  appointed 
Director  of  the  Scuola  d' applicazione  per  gli  Ingegneri.  In  1877 
he  pubhshed  his  first  work  in  Padua,  his  Lezioni  di  Statica  grajica. 
This  same  year  was  destined  to  be  of  the  first  importance  in  the 
ordering  of  his  life,  for  at  this  time,  stimulated  in  the  first  instance 
by  a  suggestion  from  the  poet  Giacomo  Zanella,  Favaro  began  to 
devote  himself  to  the  study  of  the  life  and  work  of  Galileo. 


PLATE    XXXIX 


From  a  portrait  in  the  P^odleian  brought  from  Florence  in  1661 


THE  SCIENTIFIC  WORKS   OF  GALILEO  207 

After  four  years  of  close  study  and  research,  chiefly  amongst 
the  303  volumes  of  Galileian  MSS.  and  papers  in  the  National 
Library  at  Florence,  FaVaro  came  to  the  conclusion  that  a  new 
and  complete  edition  of  Galileo's  works  was  necessary.  After  six 
years  of  strenuous  advocacy  he  had  the  satisfaction  of  seeing  his 
ideas  crowned  with  the  highest  recognition.^  On  the  20th  of 
February,  1887,  King  Umberto  issued  a  Royal  Order  decreeing 
the  publication  of  a  new  and  complete  edition  of  the  works  of 
Galileo,  at  the  cost  of  the  State,  and  under  the  care  of  the  Minister 
of  Public  Instruction.  Favaro  was  appointed  Editor-in-Chief,  and 
there  were  nominated  as  his  coadjutors  Professor  Tsidoro  Del 
Lungo,  of  the  Accademia  della  Crusca,  who  was  to  occupy  himself 
with  all  that  concerned  the  care  of  the  text,  and  Professors 
Genocchi,  Govi,  and  Schiaparelli  to  assist  in  surmounting  the 
scientific  difficulties  that  might  present  themselves.-  The  first 
volume  appeared  in  1890,  and  the  twentieth  and  last  in  1909. 
The  series  represents  a  magnificent  tribute  by  the  Italian  people 
to  the  greatest  scientific  genius  that  their  nation  has  produced. 

In  our  exposition  of  the  science  of  Galileo,  we  shall  follow  the 
chronological  order  adopted  in  the  National  Edition,  prefixing  to 
our  presentment  in  each  case  a  note  indicating  all  the  places  in 
the  National  Edition  where  the  particular  matter  is  dealt  with. 

We  desire  to  express  our  obligations  to  Mr.  John  Murray  for 
kindly  allowing  us  to  utilize  part  of  the  material  of  our  book 
Galileo  ;   His  Life  and  Work,  London,  1903. 

II.    Early  Manhood  of  Galileo,  1564-92 
1.   Training  and  Education 

Galileo  Galilei  was  born  of  Florentine  parents  at  Pisa  on  the 
15th  of  February,  1564.  Here  he  passed  the  first  ten  years  of 
his  life,  and  he  received  his  early  education,  partly  at  the  school 
of  one  Jacopo  Borghini,  and  partly  at  home,  where  he  was  helped 
in  the  study  of  Greek  and  Latin  by  his  father,  who  was  a  good 
scholar  and  mathematician,  and  an  authority  on  the  theory  and 
practice  of  music. 

At  the  age  of  twelve  Galileo  was  sent  to  the  monastery  of 

Vallombroso,  near  Florence,  for  a  course  of  the  '  Humanities  ', 

^  Intorno  ad  una  niiova  edizione  delle  Opere  di  Galileo,  Venezia,  1881. 
-  Per  la   Edizione  nazionale  delle  Opere  di  Galileo — Esposizione  e  Disegno, 
Firenzc,  1888. 


208  rHK  SCIENTIFIC.^   WORKS   OF  GALILEO 

the  iitt'rarv  <'(lu(;ati())i  then  coiiHidciod  in(liH])ensablo  for  a  well- 
horn  youth.  Here  he  made  himself  acquainted  with  the  best 
Latin  authors,  and  acquired  a  fair  eommand  of  (-licek.  For  the 
course  on  logic,  as  then  taught,  he  had  little  taste,  contenting 
himself  with  what  scra])s  of  elementary  science  and  philosophy 
he  could  pick  out  of  the  lessons. 

From  early  boyhood  Galileo  was  remarkable  for  mental 
ay)titudes  of  various  kinds,  coui)led  with  a  very  high  degree  of 
mechanical  skill  and  inventiveness.  His  favourite  pastime  was 
the  construction  of  toy-machines  or  models,  such  as  wind  and 
water  mills,  boats,  and  other  common  mechanical  contrivances. 
When  unable  to  supply  some  essential  part,  he  would  adapt  the 
machine  to  an  entirely  new  or  quaint  purpose,  never  resting 
satisfied  until  he  saw  it  work. 

As  he  grew  he  imbibed  from  his  father  something  of  the  theory 
and  practice  of  music,  and  became  skilful  with  the  lute.  He  was 
also,  it  is  said,  a  creditable  performer  on  the  organ  and  one  or 
two  other  instruments.  Music,  and  especially  the  lute,  gave  him 
pleasure  through  life  and  afforded  the  greatest  solace  in  later 
years,  when  blindness  was  added  to  his  other  afflictions.  His 
talent  in  drawing  and  painting  was  equally  striking.  In  later  life 
he  used  to  tell  his  friends  that,  had  circumstances  permitted  him 
to  choose  his  own  career,  he  would  have  decided  to  become 
a  painter.^  Galileo  was  also  very  fond  of  poetry,  and  Tiis  essays 
on  Dante,  Tasso,  and  Ariosto,  as  well  as  some  verses  and  the 
fragment  of  a  play,  bear  ^\4tness  to  a  cultivated  taste.  ^ 

In  1581,  when  seventeen  and  a  haK  years  old,  Galileo  was  sent 
to  study  medicine  and  philosophy  at  the  University  of  Pisa, 
a  course  which  his  father,  who  was  in  straitened  circumstances, 
regarded  as  hkely  to  prove  lucrative. 

2.  On  the  Pulsilogia^ 

About  a  year  after  his  matriculation  (1582-3),  Gahleo  made 
his  first  discovery — that  of  the  synchronism  of  the  oscillations  of 

^  Among  the  circumstances  which  assisted  the  rise  and  progress  of  the  re- 
formed Florentine  School,  Lanzi  includes  '  the  readiness  with  which  the  celebrated 
Galileo  imparted  to  artists  his  discoveries  and  the  laws  of  perspective  '.  History 
of  Painting,  Bohn's  edition,  vol.  i,  p.  210. 

^  These  are  collected  in  vol.  ix  of  the  National  Edition  of  his  works. 

3  Cf.  Nat.  Ed.,  vol.  x,  p.  97  ;   vol.  xix,  pp.  603,  648. 


THE  SCIENTIFIC  WORKS   OF  GALILEO 


209 


the  pendulum,  timing  the  excursions  by  his  pulse.  This  was  the 
first  attempt  at  accurate  measurement  of  any  bodily  function,  as 
well  as  the  basis  of  the  modern  clocks.  He  was  not,  however,  then 
thinking  of  clocks,  but  only  of  the  construction  of  an  instrument 
which  should  mark  with  accuracy  the  rate  of  the  pulse  and  its 
variation  from  day  to  day.  He  quickly  gave  form  to  his  idea, 
and  it  was  welcomed  with  delight  by  physicians,  and  was  long  in 
general  use  under  the  name  of  Pulsilogia.  Sancto  Santorio,  Pro- 
fessor of  Medicine  at  Padua,  was  the  first  to  give  diagrams  of  the 
Pulsilogia  in  his  Methodus  Vitandorum  Errorum  in  Arte  Medicu 
(Venice,  1602),  three  of  which  we  reproduce  (Figs.  1-3). 


-= 


n 


I    I   '    I    I   I   I   I   I    I    I   I   I   I   I   I    I   I    M   I 


I   I    ll 


IJ 


i 


Fig.  1. 


Fig.  2. 


Fig.  3. 


Fig.  1  shows  a  weight  at  the  end  of  a  strmg  held  at  the  toj)  of  a  scale,  which  can 
be  graduated  so  as  to  show  the  number  of  pulsations  per  minute.  The  string  is  gathered 
up  in  the  hand  till  the  oscillations  of  the  weight  coincide  with  the  beats  of  the  patient's  pulse. 
Then,  a  greater  length  of  string,  i.  e.  a  longer  pendulum,  would  indicate  a  slower  pulse,  and 
a  shorter  length  a  more  lively  action.  In  Fig.  2  an  improvement  is  made  by  connecting  the 
scale  and  string ;  the  length  of  the  latter  is  regulated  by  turning  the  peg  a,  and  a  bead  h . 
on  the  string  indicates  the  rate  of  pulsation.  Fig.  3  is  still  more  compact,  the  string  being 
adjusted  by  winding  (or  unwinding)  upon  an  axle  or  drum  at  the  back  of  the  dial  plate. 

In  many  of  his  subsequent  experiments  and  investigations, 
Galileo  utilized  this  principle,  as  in  his  innumerable  experiments 
on  motion,  his  long-continued  observations  on  the  periods  of 
Jupiter's  satellites,  and,  just  before  he  died,  in  the  design  ot 
a  pendulum  clock. 

Vincenzio  Viviani,  a  pupil  and  the  earliest  biographer  of  Galileo, 
tells  us  that  the  young  Galileo's  attitude  from  the  first  in  the 
philosophical  classes  was   not   at   all  to  the   satisfaction  of  his 


210  IHI^]   SCMKNTirir   WOIIKS   OF  GALILEO 

tcacliors,  owin^  to  his  hahil  ol  cxamininj^  cvory  asHertion  to  see 
wliat  it  was  worth.  In  consoquencc^  of  tlii.s  lie  soon  acquired 
a  reputation  anions  th<'  professors  and  students  for  hold  contradic- 
tion, and  was  (hd)he(l  '  Tlic  Wrangler  '.  His  (^ager  cpiestioning, 
especially  of  the  di(;tates  of  Aristotle,  found  no  favour  in  their 
eyes. 

The  first  volume  of  the  National  Edition  opens  with  what  the 
editor  calls  Juvenilia,  written  in  or  hefoni  the  year  L^84,  and 
entirely  in  Galileo's  own  hand.  They  are  commentaries  in  Latin 
on  the  De  (kielo  and  kindred  tractates  of  Aristotle,  and  are  almost 
entirely  transcripts  of  lectures  he  had  attended.  Beside  their 
personal  interest  these  Juvenilia  are  of  value  for  the  light  they 
throw  on  the  scholastic  character  of  the  teaching  then  prevalent 
in  Italy. 

3.  Galileo  and  the  State  of  Mechanics  in  Italy  at  the  end  of  the 

sixteenth  century 

Up  to  Galileo's  time  the  study  of  mathematics,  although 
included  in  the  Rotoli  or  lists  of  University  lectures,  was  practically 
neglected  in  all  the  Universities  of  Italy,  though  Commandino 
(1509-75)  and  Maurolico  (1494-1575)  had  recently  revived  a  taste 
for  the  ^vritings  of  Euclid  and  Archimedes  ;  and  Vieta  (1540-1603), 
Tartaglia  (1500-59),  Cardano  (1501-76),  and  others  had  made  con- 
siderable progress  in  algebra.  Guido  Ubaldi  del  Monte  (1540-1607),' 
soon  to  become  a  warm  friend  and  patron  of  Galileo,  Besson  (d.  c. 
1580),^  Ramelli  (1531-90),^  and  one  or  two  others  had  done  some- 
thing towards  the  application  of  statics,  the  only  part  of  mechanics 
as  yet  cultivated.  Thus  Guido  Ubaldi 's  Mechanicorum  Liber  of  1577 
consists  of  little  more  than  bald  descriptions  of  the  mechanical 
powers — the  balance,  the  lever,  the  pulley,  &c.  He  explains 
combinations  of  pulleys  at  great  length,  and  reduces  their  theory 
to  that  of  the  lever,  but  his  solution  of  the  problem  of  equilibrium 
is  very  erroneous.  The  other  contemporary  works  on  mechanics 
consist  solely  of  descriptions  of  actual  and  imaginary  machines, 
with  no  reference  to  general  principles.  There  was,  in  fact,  no 
general  recognition  of  the  necessity  of  applying  mathematics  to 
the  study  of  mechanisms. 

^  Mechanicorum  Liber,  Pisauri  (now  Pesaro),  1577. 

2  Theatrum  Instrumentorum,  Lyon,  1582. 

^  Le  diverse  ed  artificiose  macchine,  Paris,  1588. 


THE  SCIENTIFIC  WORKS   OF  GALILEO  211 

To  the  close  of  his  nineteenth  year,  Galileo  knew  nothing  of 
mathematics,  and  appears  to  have  been  first  led  to  study  geometry 
by  his  fondness  for  drawing  and  music,  the  underlying  principles 
of  which  he  wished  to  understand.  His  father  tried  to  prevent 
these  studies,  but  the  natural  bent  of  the  young  man's  mind  was 
not  to  be  denied. 

During  the  winter  and  spring  of  1582-3  the  Court  of  Tuscany 
was  at  Pisa,  and  among  the  suite  was  one  Ostilio  Ricci,  mathe- 
matical tutor  to  the  Grand-Ducal  pages,  and  a  friend  of  the 
Galilei  family.  The  tutor  and  the  young  student  became  friends. 
Going  on  one  occasion  to  pay  Ricci  a  visit,  Galileo  found  him 
lecturing  to  the  pages  on  some  problem  in  Euclid.  He  did  not 
enter,  but,  standing  by  the  door,  followed  the  instruction  with 
rapt  attention.  This  was  the  awakening  of  a  new  craving  of  the 
intellect,  under  the  influence  of  which  he  found  himself  drawn 
repeatedly  to  the  class-room.  Each  time,  concealing  himself 
behind  a  door,  he  listened,  Euclid  in  hand,  to  the  teacher's  demon- 
strations. At  last,  taking  courage,  he  begged  the  astonished  tutor 
to  help  him,  which  Ricci  readily  consented  to  do.  Henceforth, 
mathematics  were  more  studied  than  medicine,  for  which,  truth 
to  say,  he  never  showed  any  relish.  For  some  unknown  reason, 
however,  after  nearly  four  years'  residence,  and  without  taking 
the  doctor's  degree,  Galileo  withdrew  from  the  University,  and 
went  home  to  Florence  about  the  middle  of  1585,  where,  still 
under  the  guidance  of  Ricci,  he  devoted  himself  heart  and  soul 
to  mathematics  and  physics.  From  Euclid  he  passed  to  Archi- 
medes, whose  work  in  mechanics  he  was  destined  to  continue,  and 
for  whom  he  then  conceived  a  life-long  veneration.^ 

4.  The  Hydrostatic  Balance  ^ 
In  1586,  when  fresh  from  the  study  of  the  great  Syracusan's 
work  on  hydrostatics,  Galileo  constructed  a  hydrostatic  balance 
(La  Bilancetta)  for  finding  with  accuracy  the  relative  weights  of 
any  two  metals  in  an  alloy.  In  describing  it  he  refers  to  the 
popular  account  of  the  way  in  which  Archimedes  detected  the 
fraud  committed  by  the  goldsmith  in  the  making  of  Hiero's  crown. 
He  doubts  the  correctness  of  that  oft-told  story,  the  results  of 
which,  he  says,   are  fallacious,   or  at  least  little  exact,   and  he 

1  Nat.  Ed.,  vol.  i,  pp.  231-42.  2  ^f  ^at.  Ed.,  vol.  i,  pp.  211-28. 


212  THK  SCIKNTIFIC   WORKS   OF  GALILP^O 

believes    tlial    liis    own    '  most   exact    method  '    was    that    really 
employed  by  Archimedes  himself. 

Take  a  lever  a  b  (Fig.  4)  at  least  a  yard  long  (the  ioiigor  it  is, 
the  more  accurate  its  indications)  and  d(^licat(^ly  suspend  it  from 
its  centre  c,  and  at  the  end  b  let  there  be  means  of  attaching 
the  body  to  be  tested,  say  an  alloy  of  gold  and  silver,  and  its 
counter-weight  at  the  other  end  a.  First,  take  a  piece  of  pure 
gold  and  weigh  it  in  air  ;  now  immerse  it  in  water  ;  it  will  seem 
to  be  lighter,  and  the  counterpoise  d  must  be  moved  from  a  to, 
say,  E  to  obtain  a  balance.  Then,  as  many  times  as  the  space 
c  A  contains  the  space  a  e,  so  many  times  is  gold  heavier  than 
water.  Proceed  in  the  same  way  with  a  piece  of  pure  silver. 
When  placed  in  water  it  will  seem  to  lose  more  of  its  weight  than 

At ^ ' E 9 -B 


C±] 


6 


Fig.  4. 


the  gold,  and  its  counterpoise  will  have  to  be  moved  to,  say,  f, 
showing  that  silver  is  specifically  less  heavy  than  gold  in  the  ratio 
a  E  to  A  F.  Now  taking  the  alloy,  it  is  clear  beforehand  that  it 
will  weigh  less  than  an  equal  volume  of  pure  gold,  and  more  than 
an  equal  volume  of  pure  silver.  Weigh  it  in  air,  and  then  in  water, 
when  it  will  be  found  that  its  counterpoise  must  be  moved  to 
some  point  between  e  and  f,  say,  G.  From  this  we  conclude  that 
the  weight  of  the  gold  in  the  alloy  is  to  that  of  the  silver  as  F  G 
is  to  E  G. 

5.  The  Centre  of  Gravity  in  Solid  Bodies  ^ 
After  this  work  Galileo  passed  to  the  investigation  of  the 
centre  of  gravity  in  solid  bodies.  The  results  are  embodied  in  an 
essay  first  circulated  in  manuscript,  and  only  printed  in  1638, 
as  an  appendix  to  the  Leyden  edition  of  his  Dialoghi  delle  Nuove 
Scienze.  His  first  intention  was  to  prepare  an  exhaustive  treatise 
in  completion  of  the  work  of  Commandino  on  the  same  subject. 
There  chanced,  however,  to  fall  into  his  hands  the  book  of  Luca 
Valerio  (1552-1618),'  the  NeapoUtan  mathematician,  in  which  he 


1  Cf.  Nat.  Ed.,  vol.  i,  p.  182  ;   vol.  viii,  p.  313  ;   vol.  xvi,  p.  524. 

2  De  Centra  gravitatis  solidorum,  Rome,  1604. 


1 


THE  SCIENTIFIC   WORKS  OF  GALILEO  213 

found  the  matter  treated  so  fully  that  he  discontinued  his  investi- 
gations, although,  as  he  tells  us,  the  methods  he  employed  were 
quite  different  from  those  of  Valerio.  This  study,  however, 
attracted  the  attention  of  the  Marquis  Guido  Ubaldi  del  Monte  of 
Pesaro,  himself  an  able  mathematician,  who  introduced  the  author 
to  the  notice  of  Ferdinando  I,  Grand  Duke  of  Tuscany. 

Late  in  1587  Galileo  made  his  first  journey  to  Rome,  probably 
with  the  object  of  finding  there  some  opening,  or  in  furtherance  of 
liis  designs  on  the  chair  of  mathematics  at  Bologna,  which  had 
been  vacant  since  1583.  The  visit  led  to  his  acquaintance  with 
Father  Cristoforo  Clavio  (1557-1612)  of  the  Society  of  Jesus, 
a  celebrated  mathematician,  to  whom  mainly  the  world  is  indebted 
for  the  reform  of  the  calendar  in  1582.  In  later  years  he  was 
a  stout  opponent  of  the  new  astronomical  doctrines  of  the  younger 
man,  though  before  his  death  on  the  6th  of  February,  1612,  he 
l)ecame  one  of  Galileo's  most  distinguished  converts. 

Evidently  while  in  Rome  the  two  new  friends  had  been  dis- 
cussing mathematics,  for,  on  his  return  to  Florence,  Galileo  sent 
a  letter  to  Clavio,  under  date  8th  January,  1588  (the  earliest  of 
his  letters  known),  respecting  his  theorem  on  the  centre  of  gravity 
of  a  rectangular  conoid,  or  truncated  pyramid.  '  Those  ',  he  says, 
'  to  whom  he  had  already  submitted  it,  were  not  satisfied,  and, 
therefore,  he  could  not  be  so  himself.'  In  this  dilemma  he  sohcits 
the  learned  Father's  opinion,  adding  that,  '  if  it,  too,  was  unfavour- 
able, he  would  not  rest  until  he  had  found  such  a  demonstration 
as  would  be  convincing  to  all.' 

Galileo's  efforts  to  secure  employment  in  Bologna  were  frus- 
trated, and  he  was  equally  unfortunate  in  successive  applications 
for  similar  posts  at  Padua,  Pisa,  and  Florence.  Disappointed  by 
repeated  rebuffs,  he  and  a  young  Florentine  friend  decided, 
towards  the  end  of  May,  1589,  to  seek  their  fortunes  in  the  East. 
They  had  reached  Milan,  and  were  setting  out  for  \^enice  en  route 
to  Constantinople,  when  the  mathematical  chair  at  Pisa  became 
again  vacant.  Once  more  he  applied  for  the  post  ;  and  this  time 
was  successful,  through  the  joint  influence  of  his  Maecenas,  the 
Marquis  Guido  Ubaldi  del  Monte,  and  Cardinal  Francesco  del 
Monte,  brother  of  the  Marquis.  He  was  still  barely  twenty-five 
and  a  half  years  old.  The  salary  itself  was  insignificant,  only 
sixty  scudi  per  annum,  or  about  £14  of  our  money;  moreover,  the 
appointment  was  for  three  years  only,  though  renewable.  But  in 
his  needy  circumstances  even  this  meagre  opportunity  was  not  to 

2391  p 


21  i  THE  SCIKNTIFK^   WOKKS   OF  (iAJJLKO 

1)(^  rrjr(;t(Hl,  and  tho  ofHicr  would  ai'icr  all  cnahlc  hi  in  to  add  sonie- 
tliin<^'  1()  liis  means  by  private  tnition. 

().  ('ertain  Mathematical  ProblpmH 
No  sooner  was  he  settled  in  his  new  oflice  than  he  resumed 
his  pliysieo-niatlieniatieal  investigations.  in  tiie  first  y<;ar  he 
earned  to  ji^reater  len<^th  his  studies  on  tli(^  centre  of  gravity  of 
solids,  and  arrived  at  Jesuits  whieh  excitcid  afresh  the  admiration 
of  Guido  Uhaldi  del  Monte.  At  about  the  same  time  he  undertook 
the  investigation  of  that  particular  curve  which  is  described  by 
a  point  in  a  circle  (as  a  nail  in  the  rim  of  a  wheel)  while  it  revolves 
along  a  surface.  To  this  curve  thus  described  he  gave  the  name 
( 'ycloid.  This  curve  (known  as  Aristotle's  wheel)  and  its  properties 
had  long  been  a  puzzle  to  geometers,  and  had  passed  into  a  proverb 
— '  Rota  Aristotelis  quae  magis  torquet  quo  magis  torquetur.'  He 
attempted  the  problem  of  its  quadrature,  and  guessed  that  the  area 
contained  between  the  cycloid  and  its  base  is  three  times  that  of 
the  describing  circle,  but  he  was  unable  to  show  this  geometrically 
— a  task  which  his  disciple  Torricelli  (1608-47)  achieved  soon 
after  his  death. ^  Galileo  recommended  the  curve  as  a  form  of  arch 
for  bridges,  and  it  is  said  to  have  been  appHed  in  the  construction 
of  one  across  the  Arno  at  Pisa  (?  the  present  Ponte  di  Mezzo). 

Side  by  side  with  these  studies  Galileo  was  at  this  time  steadily 
revolving  those  novel  ideas  on  motion  which  were  to  be  the  basis 
of  his  latest  and  greatest  work.  In  pursuance  of  these  ideas, 
he  now  began  a  systematic  experimental  investigation  of  the 
mechanical  doctrines  of  Aristotle. 

Galileo  was  not  the  first  to  call  in  question  the  authority  of 
Aristotle  in  matters  of  science.  Cardinal  Nicholas  de  Cusa  (1401- 
64)  was  among  the  earliest  to  enter  the  lists.  ^  The  philosopher, 
Peter  Ramus  (1515-72),  was  another  early  opponent,  and  suffered 
the  penalty  for  his  convictions  in  the  massacre  of  St.  Bartholomew. 
Leonardo  da  Vinci  (1452-1519)  also  held  some  very  correct  views 
on  mechanics,  and  even  anticipated  Galileo  in  a  few  instances." 

1  Opera  Geometrica,  Florence,  1644.  Cf.  Nat.  Ed.,  vol.  xviii,  p.  153.  Huygens 
applied  the  tautochronic  property  of  this  curve  to  the  better  regulation  of  pendulum 
clocks.  ^  Cusa,  De  Docta  Ignorantia,  Paris,  1514. 

3  His  wTitings,  mostly  short  notes  and  memoranda,  were  not  known  in 
Galileo's  time.  They  remained  in  MS.,  practically  lost  to  the  world,  till  1797,  when 
Venturi  brought  them  to  light  in  his  Essai  sur  les  Ouvrages  physico-mathematigues 
de  Leonard  de  Vinci,  Paris,  1797.  Cf.  Favaro's  '  Leonardo  da  Vinci  e  Galileo ' 
(Estratto  dalla  Raccolta  Vinciana,  July  1906),  and  '  Leonard  de  Vinci  a-t-ilexerce 
une  influence  sur  Galilee  et  son  ]^cole  ?  '  {Scientia,  December  1916). 


THE  SCIENTIFIC  WORKS   OF  GALILEO  215 

Rizzoli/  again,  in  a  posthumous  work,  had  condemned  the  peri- 
patetic philosophy  in  forcible  terms,  declaring  that,  although 
there  were  many  excellent  truths  in  Aristotle's  Physics,  the 
number  was  scarcely  less  of  false,  useless,  and  ridiculous  ])ropo- 
sitions.  Giovanni  Battista  Benedetti,^  another  sixteenth-century 
writer,  had  written  expressly  to  confute  several  of  Aristotle's 
mechanical  problems,  and  so  clearly  expounded  some  principles 
of  statical  equilibrium  that  he  may  be  regarded  as  a  precursor 
of  Galileo.  Tartaglia  ^  had  discussed  the  theory  of  projectiles,  and 
Varrone  wrote  on  the  force  of  inertia,  and  recognized  the  power 
of  gravity  as  the  cause  of  accelerated  motion  in  falling  bodies. 

But  while  Galileo  was  thus  by  no  means  the  first  ta  question 
the  authority  of  Aristotle,  he  was  undoubtedly  the  first  whose 
questioning  produced  a  profound  and  lasting  effect  in  men's 
minds.  The  reason  is  not  far  to  seek.  Galileo  came  at  the  fitting 
moment,  but,  above  all,  he  came  armed  with  a  new  instrument — 
experiment. 

7.    Sermones  de  Motu  Gr avium  ^ 

The  results  of  these  earher  isolated  investigations  on  the 
foundations  of  dynamics  are  given  at  great  length  in  the  treatise 
Sermones  de  Motu  Gr  avium,  written  in  1590^  and,  as  was  then  the 
custom  of  Galileo  and  for  many  years  after,  the  work  was  first 
circulated  in  manuscript.  It  did  not  appear  in  print  until  two 
hundred  years  after  his  death, ^  and  then  in  an  incomplete  form. 
These  Sermones  consist  chiefly  of  objections  to  Aristotelian  doctrines, 
but  a  few  of  the  chapters  are  devoted  to  an  entirely  new  field  of 
speculation.  Thus,  the  11th,  13th,  and  17th  Sermones  relate  to  the 
motion  of  bodies  along  planes  inclined  at  various  angles,  and  of 
projectile  motion  ;  the  14th  enunciates  a  new  theory  of  accelerated 
motion  ;  while  in  the  16th  his  assertion,  that  a  body  falling 
naturally  for  however  great  a  time  would  never  acquire  more  than 
an  assignable  degree  of  velocity,  shows  that  he  had  alreadj^  formed 
accurate  notions  of  the  action  of  a  resisting  medium.® 

^  Rizzoli,  Antibarbarus  philosophica,  Frankfurt,  1674. 

-  Benedetti,  Speculationum  liber,  Venice,  1585. 

^  Tartaglia,  Quesiti  et  Inventioni  diverse,  Venezia,  1546. 

*  Cf.  Nat.  Ed.,  vol.  i,  pp.  245-419. 

^  In  Alberi's  Le  Opere  di  Galileo,  Florence,  1842-56. 

^  Most  of  these  theorems  were  afterwards  developed  and  incorporated  in  his 
larger  work,  Dialoghi  delle  Nuove  Scienze,  Leyden,  1638,  and  they  can  best  be 
studied  in  that  admirable  compendium. 

P  2 


21(5        mK  scikntikk;  woiiks  of  galilko 

C^alili'o  did  not  contciiL  liiui.st'lt  with  wiitinjj;  and  oirculatiiig 
liis  Stnmme.Hy  but  as  .soon  as  he  succeeded  in  demonstrating  the 
falsehood  of  any  Aristotelian  proposition  lie  did  not  hesitate  to 
(l(Mi()un('(>  it  from  his  professorial  chair. 

S.  rul)lic  ICxpc  rime  ids  on  F((lliii(j  liodu.s,  l')0()-l  ' 
From  professorial  denunciation  he  proceeded  to  those  pubhc 
experiments  w  itli  wliich  the  leaning  tower  of  Pisa  has  become  for 
ever  associated.  Aristotle  had  said  that,  if  two  different  weights 
of  tlie  same  material  were  let  fall  from  the  same  heiglit,  the  two 
would  reach  the  ground  in  a  period  of  time  inversely  proportional  to 
their  weights.  Galileo  maintained  that,  save  for  an  inconsiderable 
difference  due  to  the  disproportionate  resistance  of  the  air,  they 
would  fall  in  tlie  same  time.  The  Aristotelians  ridiculed  such 
'  blasphemy  ',  but  Galileo  determined  to  make  his  adversaries  see 
the  fact  with  their  own  eyes.  One  morning,  before  the  assembled 
professors  and  students,  he  ascended  the  leaning  tower,  taking 
with  him  a  10  lb.  shot  and  a  1  lb.  shot.  Balancing  them  on  the 
overhanging  edge,  he  let  them  go  together.  Together  they  fell, 
and  together  they  struck  the  ground. 

Neglecting  the  resistance  of  the  air,  he  now  boldly  announced 
the  law  that  all  bodies  fall  from  the  same  height  in  equal  times.  The 
correctness  of  this  law  was  easily,  if  roughly,  established  by  the 
leaning  tower  experiments,  but,  as  the  vertical  fall  was  too  rapid 
to  admit  of  exact  measurement,  he  made  use  of  the  inclined  plane 
— a  long  straight  piece  of  w^ood,  along  which  a  groove  was  accurately 
made,  and  down  which  bronze  balls  were  free  to  move  with  the 
least  friction.  With  this  he  proved  that,  no  matter  what  the 
inclination  of  the  plane,  and,  consequently,  no  matter  what  the 
time  of  fall,  the  movement  of  the  balls  was  always  in  accordance 
with  liis  law.  In  these  investigations  he  utilized  his  discovery  of  the 
isochronism  of  pendulum  oscillations  as  a  measurement  of  time. 

It  might  have  been  thought  that  such  experiments  would 
have  settled  the  question.  Yet  with  the  sound  of  the  simul- 
taneously fallen  weights  ringing  in  their  ears,  the  Aristotelians 
still  maintained  that  a  weight  of  10  lb.  would  reach  the  ground  in 
a  tenth  of  the  time  taken  by  a  weight  of  1  lb.  A  temper  of  mind 
like  this  could  not  fail  to  produce  ill-will,  and  we  learn  that,  with 
the  exception  of  the  newly  appointed  Professor,  of  Philosophy, 

1  Cf.  Xat.  Ed.,  vol.  i,  p.  249  ;   vol.  xix,  p.  606. 


THE  SCIENTIFIC^   WORKS   OF  GALILEO  217 

Jacopo  Mazzoni,  the  wliole  body  of  the  teaching  stall  now  turned 
against  their  young  colleague. 

Stimano  infamia  il  confessar  da  vecchi 
Per  falso  quel  die  giovajii  apprendero. 

Viviani,  after  Horace. 

Soon  a  wholly  unforeseen  circumstance  came  to  their  aid,  and 
led  to  Galileo's  retirement  from  Pisa.  Giovanni  de  Medici,  natural 
son  of  Cosimo  I,  was  at  the  time  Governor  of  Leghorn.  He  was 
not  unskilled  as  an  engineer  and  architect,  and  had  himself  just 
designed  a  monster  machine  which  he  wished  to  use  in  cleaning 
the  harbour.  A  model  was  submitted  to  the  Grand  Duke,  and 
Galileo  commissioned  to  examine  and  report  on  it.  He  did  so, 
and  declared  it  useless — an  opinion  which  subsequent  trial  fully 
confirmed.  Smarting  under  this  failure,  the  inventor  was  induced 
to  combine  with  the  Aristotelians,  to  whose  machinations  were  now 
added  intrigues  at  Court.  The  position  became  intolerable,  and 
Galileo  resigned  his  post  before  the  three  years'  term  had  expired, 
and  once  more  returned  to  Florence  about  the  middle  of  1592. 


III.    Life  Work,  1593-1632 
1.    Early   Years  at  Padua^ 

Galileo  had  not  long  to  wait  for  a  new  post,  for  on  the  22nd  of 
September,  1592,  he  was  appointed  to  the  mathematical  chair  in 
Padua.  Here  he  displayed  at  once  extraordinary  and  varied 
activity.  Besides  the  routine  lectures  on  Euclid,  the  Sphere,  and 
Ptolemy's  Almagest,  he  gave  special  courses  on  Military  Archi- 
tecture and  Fortifications,^  on  Mechanics,  and  on  Gnomonics. 
On  these  and  other  subjects  he  prepared  treatises  which  long 
circulated  in  manuscript  among  his  pupils.  Some  were  printed 
many  years  afterwards  ;  others,  like  the  treatise  on  Gnomonics,  are 
lost ;  while  others  again  found  their  way  into  the  hands  of  persons 
who  did  not  scruple  to  claim  and  publish  them  as  their  own. 

The  treatise  on  the  Sphere,  first  pubhshed  in  Rome  in  IQoi^,^ 
is  supposed  by  some  to  be  apocryphal,  as  it  teaches  the  Ptolemaic 
cosmogony,  placing  the  earth  immovable  in  the  centre  of  the 

^  Cf.  Nat.  Ed.,  vol.  ii,  pp.  9-146.  In  this  there  is  nothing  very  original,  his 
object  being  to  lay  before  the  student  a  compendium  of  the  most  apjiroved 
principles  of  miUtary  science  as  then  known. 

-  Trattato  della  Sfera  di  Galileo,  &c.,  by  Urbano  Daviso,  under  the  pseudonyui 
of  Buonardo  Savi.    Cf.  Nat.  Ed.,  vol.  ii,  pp.  20.5-55. 


21S         rnK  sciKN'nnc  works  of  galileo 

universe,  and  adducing  tlic  usual  ortiiudox  arguments.  But  we 
luive  it  from  Oalileo's  own  hand  that  for  many  years  he  taught  the 
Ptolemaic  systeni  in  his  elasses  in  deference  to  popular  feehng, 
altiioni^h  at  heart  he  was  even  then  a  follower  of  Copernicus.^ 

2.    On  Mechanics  - 

The  treatise  Delle.  Mcccanicht  was  written  in  1594,  and  deals 
with  the  ])owers  of  the  balance,  the  lever,  the  windlass,  the  screw, 
the  pulley,  cogged  wheels,  and  the  endless  screw  ;  and  concludes 
with  a  note  on  '  The  Force  of  Percussion  ',  added  later,  apyjarently 
in  1599.  Galileo  had  not  yet  discovered  the  principle  of  the 
decomposition  of  forces,  but  in  his  present  treatment  of  these 
subjects  he  ingeniousl}^  uses  the  theory  of  the  screw,  reducing  the 
screw  to  the  inclined  plane,  the  inclined  plane  to  the  pulley,  and 
the  pulley  to  the  simple  lever.  Here  for  the  first  time  is  mentioned 
that  condition  of  equilibrium,  regarded  from  an  entirely  new 
aspect,  to  which  modern  mechanics  owes  all  its  splendid  achieve- 
ments. This  condition  of  equihbrium  is  now  called  the  principle 
of  virtual  velocities,  and  the  credit  of  its  discovery  is  with  Gahleo, 
who  undoubtedly  perceived  its  importance. 

3.  Machine  for  Raising  Water  ^ 
While  carrjdng  on  his  professorial  duties,  giving  private  lessons, 
and  waiting  learned  tracts,  Galileo  was  occupied  in  giving  practical 
form  to  his  ideas  on  the  proper  application  of  mechanics  to 
machinerj^  Thus,  towards  the  end  of  1593,  he  devised  a  machine 
for  raising  water,  of  small  dimensions  but  of  great  power,  so  con- 
structed that  one  horse  could  raise  the  w^ater  and  distribute  it 
through  twenty  channels.  The  Venetian  Government  gave  him  the 
monopoly  of  this  invention  for  a  period  of  twenty  years,  though 
it  does  not  appear  to  have  been  used  in  a  practical  way.^ 

1  See  his  letter  to  Kepler  dated  August  4,  1597.  His  lectures  on  the  New 
Star  (p.  220,  infra)  may  be  regarded  as  his  first  public  note  of  antagonism  to  the 
ruling  astronomj'.    Cf.  Favaro,  Galileo  e  lo  Stttdio  di  Padova,  vol.  i,  pp.  148-67. 

2  Cf.  Nat.  Ed.,  vol.  ii,  p.  149  ;  vol.  viii,  pp.  216,  321. 

3  Cf.  Nat.  Ed.,  vol.  xvi,  p.  27  ;   vol.  xix,  p.  126. 

*  The  early  biographers  of  Galileo,  Viviani  and  Gherardini,  state  that  he 
was  often  employed  '  to  his  great  honour  and  profit  '  in  the  construction  or 
superintendence  of  other  machines  for  use  in  the  Venetian  State,  but  repeated 
searches  in  the  archives  of  Venice  and  Padua  do  not  afford  any  ground  for  this 
statement.  Cf.  Favaro,  Intorno  ai  servigi  straordinarii  prestati  da  Galileo  alia 
Bepublica  Veneta,  Venezia,  1890. 


THE  SCIENTIFIC   WORKS  OF  GALILEO  219 

4.    The  Geometrical  and  Military  Compass  ^ 

In  1597,  however,  he  invented  a  more  profitable  instrument, 
and  one  that  came  into  very  extensive  use,  the  Geometrical  and 
Military  Compass.  This  instrument  is  now  known  as  Gunter''-s 
Scale,  or  the  Sector.  It  consists  of  two  straight  rulers  connected 
by  a  joint  so  that  they  can  be  set  to  any  required  angle.  On  one 
side  are  four  sets  of  lines  : 

Arithmetical  lines,  which  serve  for  the  division  of  lines,  the 
solution  of  the  Rule  of  Three,  the  equalization  of  money,  the 
calculation  of  interest. 

Geometrical  lines,  for  reducing  proportionally  superficial  figures, 
extracting  the  square  root,  regulating  the  front  and  flank  forma- 
tions of  armies,  and  finding  the  mean  proportional. 

Stereometrical  lines,  for  the  proportional  reduction  of  similar 
solids,  the  extraction  of  the  cube  root,  the  finding  of  two  mean  propor- 
tionals, and  for  the  transformation  of  a  parallelopiped  into  a  cube. 

Metallic  lines,  for  finding  the  proportional  weights  of  metals 
and  other  substances,  for  transforming  a  given  body  into  one  of 
another  material  and  of  a  given  weight. 

On  the  other  side  of  the  instrument  are  : 

Polygraphic  lines,  for  describing  regular  polygons,  and  dividing 
the  circumference  of  the  circle  into  ^qual  parts. 

Tetragonical  lines,  for  squaring  the  circle  (approximately)  or  other 
regular  figure,  for  reducing  several  regular  figures  to  one  figure,  and 
for  transforming  an  irregular  rectilineal  figure  into  a  regular  one. 

Joined  lines,  used  in  the  squaring  of  the  various  portions  of 
the  circle  and  of  other  figures  contained  by  parts  of  the  circum- 
ference, or  by  straight  and  curved  lines  together. 

There  is  joined  to  the  compass  a  quadrant,  which,  besides  the 
usual  divisions  of  the  astronomical  compass,  has  transversal  lines 
for  taking  the  inclination  of  a  scarp  of  a  wall.- 

5.    The  Thermo7neter  ^ 
To  a  somewhat  later  period  may  be  referred  his  invention  of 
the  air  thermometer.     The  date  is  uncertain,  for  while  Viviani 
asserts  that  the  instrument  was  designed  during  the  first  term  of 

1  Cf.  Nat.  Ed.,  vol.  ii.  pp.  337-601  ;  vol.  xix,  pp.  167,  222. 

2  The  treatise  on  this  subject,  Le  Operazioni  del  Compasso  geomeirico  e  inililare 
(1606),  is  Galileo's  first  printed  work,  and  was  entirely  set  up  in  his  own  house 
in  Padua.  »  Cf.  Nat.  Ed.,  vol.  xvu,  p.  377. 


220 


THE  SCIKNTITK;   WOIIKS   OF  (JAJJLKO 


Fig.  o.      (Jalileo's 
thermometer. 


his  profcssorHliij)  at  I'adua  (ir){)2-8),  otluT  t'vitlcncc  takes  us  back 
only  to  about  H)(I2.  'I'lius  liciiodetto  ('astcUi  (1577-1643),  ^vritiIlg 
to  F(M(linan(lo  (Vsarini,  on  tlic  2()tli  of  September,  Hi.'JS,  says  : 

'  1  reineinber  an  experiment  wliieh  our  Si<i;nor  (ialileo  sliowcd 
me  more  tiiaii  lliirty-live  years  ago.  He  took  a  small  glass  bottle 
about  the  si/e  of  a  hen's  egg,  the  neek  of  which  was  about  two 
palms  long  (about  22  inches],  and  as  narrow  as 
a  straw.  Having  well  heated  the  bnll)  in  his  jiand, 
he  inserted  its  mouth  in  a  vessel  containing  a  litth^ 
water,  and,  withdrawing  the  heat  of  his  hand  from 
the  bulb,  instantly  the  water  rose  i]i  the  neck 
more  than  a  palm  above  its  level  in  the  vessel. 
It  is  thus  that  he  constructed  an  instrument  for 
measuring  the  degrees  of  heat  and  cold.' 

In  this  instrument  different  degrees  of  tem- 
perature were  indicated  by  the  expansion  or 
contraction  of  the  air  which  remained  in  the 
bulb ;  so  that  the  scale  was  the  reverse  of  that 
of  the  thermometer  now  in  use,  for  the  water 
would  stand  at  the  highest  level  when  the  -weather 
was  coldest.  So  long  as  the  orifice  of  the  tube 
remained  open,  this  instrument  could  not  be  an  efficient  measurer 
of  temperature,  for  it  would  be  impossible  to  distinguish  the 
effects  of  heat  and  cold  from  the  effects  of  varying  atmospheric 
pressure.  It  Avas,  in  truth,  a  barometer  as  well  as  thermometer, 
although  Galileo  did  not  recognize  this  (Fig.  5). 

His  friend  Sagredo  of  Venice  (1571-1620)  was  the  first  to 
divide  the  tube  into  100  degrees  in  1613.  Sagredo  also  appears 
to  have  experimented  with  closed  tubes  from  about  1615  ;  but 
it  was  not  until  many  years  later  (1653),  after  the  death  of  Galileo, 
that  the  jn^actice  of  closing  the  orifice,  after  exhausting  the  air, 
was  introduced.^ 

6.    Xew  Star  of  1604  - 

In  1604  a  new  star  appeared  with  great  si)lendour  in  the  con- 
stellation Serpentaiius.    Maestlin,  one  of  the  first  to  notice  it,  says : 
'  How'  wonderful  is  this  new  star  !    I  am  certain  that  I  did  not 

^  The  credit  of  this  capital  improvement  is  due  to  Leopoldo  de'  Medici, 
brother  of  Ferdinando  II,  Avho  adopted  the  plan  of  filling  the  tube  with  spirit, 
boiling  it,  and  sealing  the  orifice  whilst  the  contained  spirit  was  in  an  expanded 
state,  thus  obtaining  a  partial  vacuum,  and  depriving  the  instrument  of  its 
barometrical  property.  -  Cf.  Xat.  Ed.,  vol.  ii,  pp.  269-305,  526. 


THE  SCIENTIFIC  WORKS   OF  GALILEO  221 

see  it  before  the  29tli  of  September,  nor,  indeed,  on  account  of 
several  cloudy  nights  had  I  a  good  view  till  the  6th  of  October. 
Now  that  it  is  on  the  other  side  of  the  sun,  instead  of  surpassing 
Jupiter  as  it  did,  and  almost  rivalling  Venus,  it  scarcely  equals 
the  Cor  Leonis,  and  hardly  surpasses  Saturn.  It  continues,  how- 
ever, to  shine  with  the  same  bright  and  strongly  sparkling  light, 
and  changes  colour  almost  every  moment,  now  tawny,  then 
yellow,  presently  purple  and  red,  and,  when  it  has  risen  above  the 
vapours,  most  frequently  white.' 

Gahleo  appears  to  have  noticed  the  new  star  about  the  15th  of 
October.  The  appearance  of  the  new  phenomenon  had  given  rise 
to  the  most  bewildering  statements.  Some  said  it  was  a  Ught 
in  the  inferior  regions  of  space,  in  '  the  elementary  sphere  ',  that 
is,  in  that  sphere  of  the  four  elements  below  that  heavenly 
and  incorruptible  region  where  the  Aristotelian  school  placed 
the  heavenly  bodies.  Others  thought  that  it  was  an  old  star 
hitherto  unnoticed  ;  others  again  believed  that  it  was  a  new 
creation,  while  the  astrologers  deduced  from  it  the  wildest 
forebodings. 

After  observing  the  new  star  for  some  time,  Galileo  expounded 
his  views  upon  it  in  three  extraordinary  lectures,  which  were 
dehvered  to  the  public  in  the  great  hall  of  the  University  in 
December,  1604.  Unfortunately,  only  fragments  of  these  lectures 
have  come  down  to  us,  but  from  these  and  one  or  two  other 
references,^  we  learn  that  his  purpose  was  to  indicate  the 
position  of  the  new  phenomenon  as  '  far  above  the  sphere  of 
the  Moon '. 

Now,  unlike  his  contemporaries,  Tycho  Brahe  and  Kepler,  who 
thought  that  new  stars  were  temporary  conglomerations  of  a 
vapour-fiUing  space,  Galileo  had  suggested  that  they  might  be 
products  of  terrestrial  exhalations  of  extreme  tenuity,  at  immense 
distances  from  the  earth,  and  reflecting  the  sun's  rays — an  hypo- 
thesis which,  as  we  shall  see  later  on,  he  also  applied  to  comets. 
From  the  absence  of  parallax  he  showed  that  the  new  star  could 
not  be,  as  the  current  theory  held,  a  meteor  engendered  in  our 
atmosphere,  and  nearer  to  us  than  the  moon,  but  that  it  must  be 
situated  beyond  the  planets  and  among  the  remote  heavenly 
bodies.      This    was    inconceivable     to     the     Aristotelians,    who 

^  Cf.  Dijesa  contro  alle  Calunnie  di  Baldassare  Capra,  Nat.  Ed.,  vol.  ii,  and 
Postille  al  Libro  d' Antonio  Rocco,  Nat.  Ed.,  vol.  vii. 


222  THK   SCIKXTIFKl    WOi^KS   OF  (iALII.KO 

lliouglit  ()l  tlic  outer  sjilitTc  ol  the  UiiivcrHC  as  au  iucuniiptible 
and  uiicliangeable  heaven,  subject  neitlier  to  growth  nor  to  decay, 
where  nothing  was  created  or  destroyed. 

7.    On  Magnetism  ' 

Gahleo's  study  of  tlie  magnetic  properties  ol  tlu;  loadstone 
dates  Iroiii  about  1600,  apparently  after  he  had  seen  the  J)e 
Magnete  of  William  Gilbert  of  Colchester  (1544-1600),  which  was 
published  in  London  in  1600.  Gilbert's  book  had  very  great 
attraction  foi-  him,  firstly,  because  its  arguments  traversed  many 
of  the  principles  of  the  Aristotehan  school,  and  secondly,  because 
it  contained  a  number  of  original  experiments,  coupled  with 
philosophical  reflections  of  a  far-reaching  kind  which  appealed  to 
his  own  daring  spirit.  Both  8agredo  and  Paolo  Sarpi  (1552-1623), 
ins  Venetian  friends,  tell  us  that  at  this  time  (1602)  Galileo  had  not 
only  repeated  many  of  Gilbert's  experiments,  but  made  new  ones  of 
his  own,  especially  on  the  best  method  of  arming  loadstones. 

During  the  long  vacations  at  Padua  Galileo  was  wont  to  return 
to  Florence,  where  he  gave  lessons  to  the  young  Prince  Co^mo 
de'  Medici.  In  the  summer  of  1607  he  had  evidently  been  re- 
hearsing the  wonderful  properties  of  loadstones,  and  on  returning 
to  Padua  he  sent  his  pupil  a  stone  which  he  had  picked  up  in 
Venice,  about  ^  lb.  in  weight,  not  elegant  in  form  but  very  powerful. 
In  the  letter  which  accompanied  it  he  speaks  of  another  stone 
belonging  to  Sagredo. 

'  This  is  elegantly  shaped,  and  weighs  about  5  lb.  I  have  made 
it  capable  of  sustaining  5^  lb.  of  iron,  and  I  think  I  can  make  it 
do  more  before  it  leaves  my  hands.  Much  diligence  is  required  in 
finding  the  true  poles  of  these  stones,  that  is,  where  their  virtue 
is  most  robust,  and  where,  consequently,  their  full  sustaining  power 
is  manifested.  This  sustaining  force  depends  as  much  on  the 
quahty  of  the  armature  as  on  the  stone  itself.  Not  every  piece  of 
iron  of  any  size  and  shape  is  equally  sustained,  but  well-made 
steel  of  a  particular  size  and  figure  is  most  powerfully  attracted. 
Then  again,  a  slight  shifting  of  the  armatiu:es  from  their  true 
positions  causes  a  great  variation  in  the  sustaining  force.  In 
the  last  four  days  I  have  so  arranged  that  the  stone  now  bears 
1  lb.  more  than  its  o\^aier  was  ever  able  to  make  it  carry,  and 
I  hope,  after  preparing  some  pieces  of  the  finest  steel,  to  make  it 
sustain  still  more.' 

^  Cf.  Xat.  Ed.,  vol.  ill,  p.  279  et  seq . ;  vol.  x,  pp.  89, 185  et  seq.  ;   vol.  xiii,  p.  328. 


THE  SCIENTIFIC  WORKS   OF  GALILEO  223 

He  then  describes  a  curious  case  of  what  is  now  called  super- 
posed magnetism  : 

'  I  have  also  observed  in  this  stone  another  admirable  effect 
which  I  have  not  met  with  in  any  other,  namely,  that  the  same  pole 
repels  or  attracts  the  same  piece  of  iron  according  to  distance. 
Thus,  placing  an  iron  baU  on  a  smooth  and  level  table,  and  quickly 
presenting  the  stone,  at  a  distance  of  about  one  finger,  the  ball 
moves  away,  and  can  be  chased  about  at  pleasure.  But  now, 
when  the  stone  is  sharply  withdrawn  to  a  distance  of  about  four 
fingers,  the  ball  moves  towards  it,  and,  with  a  little  dexterity,  can 
be  made  to  follow  it  about.' 

Ultimately  Galileo  was  able  to  secure  this  stone  also  for  Prince 
Cosimo,  and  in  an  accompanying  letter  to  Chief  Secretary  Belisario 
Vinta,  dated  3rd  May,  1608,  he  writes  : 

'  I  send  for  his  Highness  the  loadstone  which,  after  many 
experiments,  I  have  finally  made  to  sustain  a  weight  of  12  lb.,  or 
more  than  double  its  own,  and  I  am  certain  that,  had  I  more  time 
and  more  suitable  tools  at  my  disposal,  I  could  have  done  better 
still.  I  have  fashioned  the  two  armatures  in  the  form  of  anchors, 
in  allusion  to  the  fable  of  a  stone  so  large  and  powerful  as  to  hold 
securely  a  ship's  anchor.  The  form  is  also  convenient  for  attaching 
weights  to  measure  its  holding  capacity.  I  have  purposely  not 
made  these  anchors  equal  to  the  largest  weights  that  I  know  the 
stone  will  carry,  first,  to  leave  a  margin  of  safety,  so  that  it  will 
hold  them  firmly  when  presented,  and  secondly,  because  I  am  of 
opinion  that  its  power  may  vary  according  to  locality  with  respect 
to  the  poles  of  the  great  magnet,  the  earth  ;  for,  whereas  along  the 
equinoctial  line  both  poles  will  be  of  equal  strength,  one  may  be 
more  powerful  than  the  other  in  the  northern  hemisphere,  and 
vice  versa  in  the  southern.  Hence  I  am  led  to  believe  that  the 
more  powerful  pole  sustains  here  in  Padua  somewhat  more  than 
it  can  in  the  more  southerly  latitude  of  Florence  or  Pisa.^  .  .  . 

'  I  have  marked  the  poles,  so  that  one  can  readily  see  where  the 
anchors  or  armatures  should  be  applied ;  that  with  the  greater 
weight  should  be  attached  to  the  more  robust  pole,  and  the  less 
heavy  one  to  the  weaker  pole,  taldng  care  to  apply  them  at  the 
same  instant,  for  I  have  found,  not  without  great  astonishment, 
that  the  stone  more  willingly  supports  two  weights  together  than 
one  alone.  Thus,  a  piece  of  iron,  so  heavy  as  not  to  be  supported 
when  aj)plied  alone,  will  be  held  if  at  the  same  time  another  piece 
is  applied  to  the  other  pole.  ...  I  have  in  mind  some   other 

^  Here  he  confuses  two  properties  of  the  magnet,  (1)  its  portative  force,  and 
(2)  its  directive  force  or  '  inclination  '. 


224  INK   SCIKNTIKK'    WOI^KS   OK   (iAhlLEO 

aititict's  to  icndci-  tlic  stone  still  iiioio  nuirvellowsly  j)()wcif ill,  and 
1  am  ccrtaiii  tluit  I  shall  not  fail.  I  hclicvc^  J  can  mak(^  it  sustain 
four  times  its  own  \v(Mjj;ht,  or  20  II).,  uliicli,  for  such  a  lai'^c  stone, 
is  soincthiu^';  very  adniirabk!.  indeed,  I  havt;  no  douf)t  that  with 
proper  cutting  it  can  be  made  to  sup])ort  more  tlian  .*J0,  and  even 
•40  11).  I  have  noticed  in  this  stone,  not  only  that  it  never  tires 
of  holding  a  weight,  but  that  with  time  it  invigorates  itself  the 
more.'  ^ 

The  '  other  artifices  '  referred  to  in  the  letter  consisted  in 
))reaking  up  large  stones,  shaping  the  best  pieces  so  as  to  Vjring 
out  tlunr  maximu7Ti  of  polarity,  and  providing  them  with  suitaVjle 
armatures,  with  the  result  that  the  portative  force  of  the  selected 
])ieces  far  exceeded  his  own  first  and  Gilbert's  achievements  in  the 
same  direction.  Thus,  in  the  De  Magnete,^  the  English  philosopher 
speaks  of  a  stone  (weight  not  given)  which  normally  could  sustain 
4  oz.  of  iron,  but  which,  when  capped  with  steel,  could  support 
12  oz.  '  But ',  he  goes  on,  '  the  greatest  force  of  a  combining,  or 
rather  united,  nature  is  seen  when  two  stones,  armed  with  iron 
caps,  are  so  joined  by  their  concurrent  (commonly  called  contrary) 
ends  that  they  mutually  attract  and  raise  one  another.  In  this 
way  a  w^eight  of  20  oz.  of  iron  is  raised,  when  either  stone  unarmed 
would  only  allure  4  oz.' 

Galileo  went  far  beyond  this,  since  he  was  able  to  fashion 
small  stones  of  extraordinary  power.  Of  such  a  one  he  speaks  in 
a  letter  to  Cesare  Marsili,  dated  27th  June,  1626.  It  weighed 
6  oz.,  and  unarmed  could  only  support  2  oz.,  but  when  armed  it  was 
able  to  sustain  160  oz.,  or  tw^enty-six  times  its  own  weight.  He 
had  this  by  him  when  writing  his  Dialogue  of  1632,  where  he 
speaks  of  it  as  still  in  his  possession.  Later  he  appears  to  have 
presented  it  to  the  Grand  Duke  of  Tuscany,  Ferdlnando  II,  as  we 
gather  from  Castelli's  Discorso  sopra  la  Calamita  {circa  1639-40).^ 

^  These  tAso  stones  were  lost  in  after  years,  for  in  1698  Leibnitz  searched  for 
them  in  vain. 

2  Chapter  XVII,  book  11. 

^  This  stone  is  now  preserved  in  the  Tribuna  di  Galileo,  Florence.  The  weight 
is  in  the  form  of  a  tomb  {sepolcro),  a  form  which  was  probably  suggested  by  the 
legend  of  Mohammed's  coffin  suspended  in  the  air  by  loadstones. 

The  Editor  of  the  Florentine  edition  of  Galileo's  Works,  1718,  mentions 
another  small  stone  fashioned  by  Galileo,  and  of  still  more  extraordinary  power. 
It  weighed  only  three-tenths  of  a  grain,  yet  could  support  121  grains  (vol.  i, 
Preface,  p.  xlvi).  This,  if  true,  beats  Sir  Isaac  Newton's  stone,  which  he  wore 
set  in  a  ring.    It  weighed  3  grains,  and  was  able  to  support  746  grains. 


THE  .SCIENTIFIC  WORKS   OF  GALILEO  225 

8.    Development  of  Galileo'' 8  Ideas  on  Mechanics,  1590-1609  ^ 

In  the' years  1590  to  1609,  Galileo  completed,  or,  at  least,  laid 
the  foundations  of,  his  Dialoghi  delle  Nuove  Scienze  of  1638.  In 
the  6th  Day  of  these  dialogues,  he  speaks  of  Paolo  Aproino  as 
assisting  at  a  great  number  of  experiments  in  Padua  on  diverse 
problems  in  mechanics,  and  especially,  '  on  the  marvellous  prob- 
lems of  percussion  '.  On  the  29th  of  November,  1602,  we  find  him 
writing  to  the  Marquis  Guido  Ubaldi  on  the  fall  of  bodies  through 
two  successive  chords  of  a  quadrant  (discussed  in  3rd  Day), 
and  on  pendulum  oscillations  of  different  amplitudes.  In  1604-6 
he  further  studied  the  properties  of  the  inclined  plane,  and  took 
up  the  subject  of  naturally  accelerated  motion  (discussed  in 
3rd  Day).  During  1609  he  was  occupied  with  the  strength  of 
beams  and  their  resistance  to  fracture  (discussed  in  2nd  Day). 
In  the  same  year  he  investigated  the  motion  of  projectiles  as 
applied  to  artillery,  using  the  experiences  derived  from  his  many 
visits  to  the  arsenal  in  Venice  (discussed  in  4th  Day),  and  the 
coherence  of  the  particles  of  solid  bodies  (discussed  in  1st  Day). 
In  fact,  about  May,  1609,  he  was  intending  to  pubUsh  an  account 
of  all  these  studies  as  a  complete  system  of  mechanical  philosophy, 
when  the  telescope  and  consequent  astronomical  work  intervened, 
and  turned  his  energy  in  another  direction. 

Writing  of  this  period,  1602-9,  Favaro  says : 

'  In  truth  the  house  of  Galileo  in  Padua  was  not  only  a  place 
for  genial  intercourse  ;  not  only  a  school  to  which  flocked  students, 
ItaUans  and  foreigners  from  every  country  in  Europe,  but  more 
than  this,  it  was  a  laboratory,  where  his  marvellous  mechanical 
talent  knew  how  to  devise  ever  new  expedients.  It  was  an  academy 
in  the  true  sense  of  the  word,  where  the  gravest  problems  in 
physics,  in  mechanics,  in  astronomy,  and  in  mathematics  were 
discussed  with  perfect  freedom,  and  where  it  was  possible  to 
submit  the  deductions  of  reason  to  the  salutary  test  of  experiment, 
and  the  results  of  experiments,  in  their  turn,  to  reasoning  and 
calculation.  Thus  it  may  be  said  that  the  principal  problems  in 
the  Dialoghi  delle  Nuove  Scienze  were  raised  and  discussed  within 
the  walls  of  Padua.'  ^ 

1  Cf.  Nat.  Ed.,  vol.  ii,  p.  259  ;  vol.  x,  pp.  97,  228,  244,  248. 

-  Galileo  e  lo  Studio  di  Padova,  2  vols.,  Firenze,  1883,  vol.  i,  p.  314.  Much 
the  same  may  be  said  of  his  Dialogue  of  1632,  where  many  of  the  arguments  arc 
drawn  from  his  experiments  in  Padua. 


22t)  INK   SCIKNTIFK'    WOPvKS   OK  (^\LIL^:() 

(Jiililco  had  lonij;  been  dcsiious  to  jvliiiii  to  liis  native  'riiscaiiy, 
and  lie  MOW  {  M)()9)  oprncd  iicgotiatiojis  with  tlic  ('liici  Secretary 
of  the  (iraiid  Duke,  oxplaiiiiii^  that  what  he  especially  Hought  was 
leisure  to  puisne  his  researches  without  the  dist i-actioii  an<l  stfaiii 
of  teaching  and  leet  nrinii;. 

"  Tlie  works  w  hicii  L  have  to  linisli  ',  hv.  wrote  in  May  lOliJ, 
'are  chiefly:  (1)  two  books  on  the  system  or  structure  of  the 
Universe,  an  ininiense  ujidertaking  full  of  ])hilosophy,  astronomy, 
and  geometry  ;  (2)  three  books  on  local  motion,  a  science  entirely 
new,  no  one,  ancient  or  modern,  having  discovered  any  of  the 
many  admirable  consequences  which  ]  demonstrate  in  natural  ajid 
\  iolent  motions,  so  that  I  may  with  reason  call  it  a  new  science 
invented  by  me  from  its  very  first  principles  ;  (3)  three  books  on 
mechanics,  two  of  them  on  the  demonstration  of  principles,  and 
one  of  problems.  Although  others  have  treated  this  subject,  no 
one  either  in  quantity  or  quahty  has  done  a  quarter  of  what  I  am 
writing  on  it.  I  have  also  treatises  on  natural  subjects  such  as  on 
sound  and  speech  ;  on  light  and  colours  ;  on  the  tides  ;  on  the 
composition  of  continuous  quantity ;  on  the  movements  of 
animals ;  and  others.  I  have  also  an  idea  of  vn^iting  some  books 
relating  to  the  military  art.  .  .  . 

'  Then  I  need  not  say  what  an  amount  of  labour  will  be  required 
to  fix  the  periods  of  the  four  new  planets,  a  task  the  more  laborious 
the  more  one  thinks  of  it,  as  they  are  separated  from  one  another 
by  very  brief  intervals,  and  are  all  very  similar  in  size  and 
colour.' 

Some  of  the  treatises  named  in  this  letter  are  now  lost,  partly 
through  the  accidents  of  Galileo's  stormy  life,  and  in  transport 
from  place  to  place,  and  partly,  through  the  extraordinary  negli- 
gence and  criminality  of  custodians.  The  loss  of  the  essay  on 
Continuous  Quantity  is  particularly  to  be  regretted.  It  is  to  his 
early  disciple  Buonaventura  Cavalieri  (1598-1647),  who  refused  to 
publish  his  own  book  ^  so  long  as  he  hoped  to  see  Galileo's  printed, 
that  we  owe  The  Method  of  Indivisibles,  which  is  recognized  as 
containing  some  of  the  germinal  ideas  of  Newton's  Fluxional 
Calculus.  The  treatises  on  Sound  and  Speech,  and  on  Light  and 
Colours,  were  probably  never  completed,  but  we  find  fragments 
of  them  in  later  works,  as,  II  Saggiatore  and  the  Dialogues  of  1632 
and  1638.  Similarly,  of  the  movements  of  animals  we  have  the 
fragment  Intorno  al  camminare  del  cavallo.^ 

^  Geometria  indivisibilibus  continuorum  nova  quadam  ratione  iiromota,  Bologna, 
1635.  2  Xat.  Ed.,  vol.  viii,  last  section. 


^  c 

O  ~a 

■/)  c 

— i  o 


7)     ^ 

'o  ^ 

^  -a 


o 
'-J 


O 

o 


THE  SCIENTIFIC   WORKS   OF  GALILEO  227 

9.    The  Invention  of  the  Telescope  ^ 

Leaving  aside  the  vexed  question  of  the  priority  of  invention 
of  the  telescope,  and  of  the  reports  of  it  which  circulated  in  Italy 
from  about  November  1608,'^  we  pass  to  GaHleo's  own  account 
of  his  share  in  the  discovery.  Of  this  there  are  three  slightly 
discordant  versions — one  to  his  brother-in-law,  Landucci,  dated 
29th  August  1609,  the  second  in  Sidereus  Nuncius,  published  in 
March  I6I0,  and  the  third  in  II  Saggiatore,  1623.  In  the  first 
version  (probably  the  most  reliable,  as  being  nearest  in  time) 
he  says  : 

'  I  write  now  because  I  have  a  piece  of  news  for  you,  though 
whether  you  will  be  glad  or  sorry  to  hear  it  I  cannot  say,  for  I  have 
now  no  hope  of  returning  to  my  own  country,  though  the  occur- 
rence which  has  destroyed  that  hope  has  had  results  both  useful 
and  honourable.  You  must  know  then  that  about  two  months 
ago  (i.  e.  about  June  1609)  a  report  was  spread  here  that  in 
Flanders  a  spy-glass  had  been  presented  to  Prince  Maurice,  so 
ingeniously  constructed  that  it  made  the  most  distant  objects 
appear  near,  so  that  a  man  could  be  seen  quite  plainly  at  a  distance 
of  two  miles.  This  result  seemed  to  me  so  extraordinary  that  it 
set  me  thinking,  and,  as  it  appeared  to  me  that  it  depended  upon 
the  laws  of  perspective,  I  reflected  on  the  manner  of  constructing 
it,  and  was  at  length  so  entirely  successful  that  I  made  a  spy-glass 
which  far  surpasses  the  report  of  the  Flanders  one.  As  the  news 
had  reached  Venice  that  I  had  made  such  an  instrument,  six  days 
ago  I  was  summoned  before  their  Highnesses  the  Signoria,  and 
exhibited  it  to  them,  to  the  astonishment  of  the  whole  Senate. 
Many  of  the  nobles  and  senators,  although  of  a  great  age,  mounted 
more  than  once  to  the  top  of  the  highest  church  tower  in  \^enice, 
in  order  to  see  sails  and  shipping  that  were  so  far  off  that  it  was 
two  hours  before  they  were  seen  without  my  spy-glass,  steering 
full  sail  into  the  harbour  ;  for  the  effect  of  my  instrument  is  such 
that  it  makes  an  object  50  miles  off  appear  as  large  as  if  it  were 
only  five  miles  away. 

'  Perceiving  of  what  great  utility  such  an  instrument  would 
prove  in  naval  and  mihtary  operations,  and  seeing  that  his  Serenity 
the  Doge  desired  to  possess  it,  I  resolved  on  the  24th  inst.  to  go  to 
the  palace  and  present  it  as  a  free  gift.    On  quitting  the  presence- 

1  Cf.  Nat.  Ed.,  vol.  iii,  pp.  18,  60,  869 ;  vol.  x,  pp.  250-3  ;   vol.  xix,  p.  587. 

■^  Favaro  discusses  these  questions  very  fully  in  Galileo  e  lo  Stvdio  di  Padoua, 
vol.  i,  ch.  xi,  and  in  La  Invenzione  del  Telescopio  secondo  gli  tdtimi  Studi, 
Venezia,  1906.  Cf.  Drinkwater's  Life  of  Galileo,  1833,  pp.  20-6  ;  Grant's  Hisloru 
of  Physical  Astronomy,  1852,  pp.  514-37. 


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THE  SCIENTIFIC  WORKS   OF  GALILEO  229 

chamber  I  was  commanded  to  bide  awhile  in  the  hall  of  the 
Senate,  whereunto  the  Procurator,  Antonio  Prioli,  one  of  the 
heads  of  the  University  of  Padua,  came,  and,  taking  me  by  the 
hand,  said  that  the  Senate,  laiowing  the  way  in  which  I  had  served 
it  for  seventeen  years  at  Padua,  and  being  sensible  of  my  courtesy 
in  making  it  a  present  of  the  spy-glass,  had  ordered  my  election 
(with  my  goodwill)  to  the  Professorship  for  life.' 

This  telescope  is  unfortunately  lost.  It  is  mentioned  with 
some  particulars  in  his  Sidereus  Nuncius,  and  consisted  of  a  leaden 
tube,  with  a  plano-concave  eye-glass  and  a  plano-convex  object- 
glass,  and  had  a  magnifying  power  of  three  diameters.  From  other 
sources  we  learn  that  the  tube  was  2-39  metres  long  and  about 
42  millimetres  diameter  (see  Fig.  6,  p.  228).  This  instrument  was 
shown  for  the  first  time  in  public  on  the  21st  of  August^  1609, 
from  the  top  of  the  campanile  of  San  Marco,  when  the  farthest 
object  that  could  be  seen  clearly  was  the  campanile  of  the  Church 
of  San.  Giustina  in  Padua,  distant  about  35  kilometres. 

10.    Invention  of  the  Microscope  ^ 

The  invention  of  the  telescope  could  hardly  fail  to  lead  to  the 
disclosure  of  the  principle  of  the  microscope,  which  at  first  was 
but  a  telescope  adapted.  John  Wodderborn,  a  Scotch  student 
who  attended  Galileo's  lectures  at  Padua,  in  a  defence  of  his 
master  (published  in  1610),^  states  that  he  '  heard  Galileo  describe 
in  what  manner  he  perfectly  distinguishes  with  hig  telescope  the 
organs  of  motion  and  of  the  senses  of  the  smaller  animals,  especi- 
ally in  a  certain  insect  which  has  each  eye  covered  b}^  a  rather 
thick  membrane,  which,  perforated  with  seven  holes,  like  the 
visor  of  a  warrior,  alloAvs  it  sight  \^ 

In  1614,  the  Frenchman,  Jean  Tarde,  called  on  Galileo,  whom 
he  found  ill  in  bed,  and  he  says  that 

'  Galileo  told  me  that  the  tube  of  a  telescope  for  observing  the 
stars  is  no  more  than  2  feet  in  length  ;  but  to  see  objects  well, 
which  are  very  near,  and  which  on  account  of  their  small  size 
are  hardly  visible  to  the  naked  eye,  the  tube  must  be  two  or  three 
times  longer.  He  tells  me  that  with  this  long  tube  he  has  seen 
flies  which  look  as  big  as  a  lamb,  are  covered  all  over  with  hair, 

^  Cf.  Nat.  Ed.,  vol.  xiii,  pp.  36,  40,  199,  201,  208. 

^  John  Wodderborn,  Scotobritannus,  Quatuor  problematum  quae  Martinus 
Horky  contra  Nuntium  Sidereum  de  quatuor  planetis  novis  disputanda  proposuit 
confutatio,  Padua,  1610. 

^  Nat.  Ed.,  vol.  iii,  pp.  151-78. 

2391  Q 


230  TUK   S(MKNTIFir   WORKS   OF   (IWALKO 

and  have  very  pointed  nails,  by  means  ol  wliieii  tliey  keo|)  ilicm- 
sclves  uj)  and  walk  on  glass,  althougli  hanging  feet  upwards.'  ^ 

In  //  Sagyialorc  and  in  N'iviani's  biographieal  sketch  there  are 
similar  referenci^s,  the  latter  adding  that  in  ]()12  (iahleo  y)resented 
a  niieroscope  to  the  King  of  Poland.  All  this  shows  that  he  was 
well  ae(piainted  from  the  first  with  the  use  of  his  invention  qua 
microscope.  For  many  years,  however,  he  gave  tlu^  matter  little 
attention — not,  indeed,  until  his  visit  to  Romc^  in  1624,  when  he 
found  the  microscope  discussed  as  a  novelty  whicli  nobody  could 
understand. 

An  optician  of  Middelburg  had  invented  a  form  of  microscope 
about  1590,  in  which  objects  were  seen  inverted.  One  of  these 
instruments  he  ])resented  to  the  Archduke  diaries  Albert  of 
Austria,  who  in  turn  gave  it  to  Cornelius  Drebbel,  a  Dutchman, 
then  living  in  London.  For  many  years  after,  the  instrument 
was  practically  forgotten ;  but  about  1621  Cornelius  Drebbel 
appears  to  have  resumed  its  manufacture."  In  the  following  year 
Jacob  Kuffler,  a  relative  of  Drebbel,  brought  a  specimen  to  Rome, 
a  present  from  Nicholas  Fabri  de  Peiresc  of  Paris  (1580-1637)  to 
one  of  the  Cardinals.  Unfortunately,  Kuffler  died  before  he  had 
time  to  explain  the  management  of  the  instrument,  and  so  it 
remained  a  mystery.  Two  years  later  two  other  specimens  arrived, 
also  sent  by  de  Peiresc,  with  brief  instructions  as  to  their  use. 
One  of  these  was  nothing  more  than  a  magnifying  glass,  but  of 
the  other,  consisting  of  two  glasses,  nobody  in  Rome  could  make 
anything,  '  although  they  had  the  help  of  mathematicians  '. 

At  this  moment  Galileo  arrived.  The  instrument  was  show^n 
him,  and  he  at  once  told  his  friends  that  he  had  himself  made 
a  somewhat  similar  instrument  many  years  previously,  '  which 
magnified  things  as  much  as  50,000  times,  so  that  one  sees  a  fly 
as  large  as  a  hen  '.  He  made  some  specimens,  showing  objects 
erect,  which  he  sent  to  his  friends,  and  soon  his  microscopes  were 
in  as  great  request  as  his  telescopes.  Amongst  others,  he  sent  one 
to  Prince  Federigo  Cesi,  on  the  23rd  of  September,  1624,  with  the 
following  letter  : 

^  Cf.  Nat.  Ed.,  vol.  xix,  p.  589.  Tarde's  voyages  in  Italy  are  in  MS.  at  the 
Bibliotheque  nationale,  Paris. 

^  Charles  Singer,  '  Notes  on  the  Early  History  of  the  Microscope  ',  in  the 
Proceedings  of  the  Royal  Society  of  Medicine,  Historical  Section,  1914,  vol.  vii, 
p.  247,  and  '  The  Dawn  of  Microscopical  Discovery,'  Journal  of  the  Royal  Micro- 
scopical Society,  1915,  p.  317,  and  the  article  bj-  him  in  this  volume. 


THE  SCIENTIFIC  WORKS   OF  GALILEO  231 

'  I  send  your  Excellency  a  little  spy-glass  [occhialhw)  for 
observing  at  close  quarters  the  smallest  objects,  which  I  hope 
will  afford  you  the  same  interest  and  pleasure  that  it  has  to  me. 
I  delayed  sending  it  because  my  first  attempts  were  imperfect  by 
reason  of  the  difficulty  in  fashioning  the  lenses.  The  object  is 
placed  on  a  movable  circle  (at  the  base  of  the  instrument),  which 
can  be  turned  in  such  a  way  as  to  show  successive  portions, 
a  single  pose  being  unable  to  show  more  than  a  small  part  of  the 
whole.  As  the  distance  between  the  lerts  and  the  object  must  be 
precisely  adjusted  in  order  to  see  things  that  are  in  rehef,  it  is 
necessary  to  bring  the  glass  nearer  to  or  farther  from  the  object 
according  to  the  parts  to  be  examined.  Therefore  the  little  tube 
is  made  adjustable  on  its  stand  or  guide.  The  instrument  should 
be  used  in  a  strong  light,  or  even  in  full  sunlight,  so  as  to  illuminate 
the  object  as  much  as  possible. 

'  I  have  examined  with  the  greatest  delight  a  large  number  of 
animals,  amongst  which  the  bug  is  most  horrible,  the  gnat  and  the 
moth  very  beautiful.  I  have  also  been  able  to  discover  how  the 
fly  and  other  little  animals  are  able  to  walk  on  windows-panes  and 
ceiHngs  feet  upwards.  But  your  Excellency  will  now  have  the 
opportunity  of  observing  thousands  of  other  details  of  the  most 
curious  kind,  of  which  I  shall  be  glad  to  have  an  account. 

'  P.S. — The  little  tube  is  in  two  pieces,  so  that  you  may 
lengthen  it  or  shorten  it  at  pleasure.'  ^ 

11.    The  Siderius  Nuncius 

First  Telescopic  Discoveries  in  the  Heavens  ~ 

After  exhibiting  his  telescope  in  Venice,  Gahleo  returned  to 
Padua,  and  at  once  constructed  a  third  instrument,  of  which  he 
only  says  that  '  it  made  objects  appear  more  than  sixty  times 
larger  ',  equivalent  to  a  magnifying  power  of  about  eight  diameters. 
But  in  a  very  few  days  he  had  a  much  better  telescope  which 
enlarged  four  hundred  times.  With  this  in  the  autumn  of  1609  \ 
he  made  his  first  discoveries  in  the  heavens — an  immense  number 
of  fixed  stars,  more  than  tenfold  the  number  at  that  time  cata- 
logued.    He  noticed  the  propertj^^  of  irradiation  common  to  all 

^  The  only  relics  (two  tubes)  of  these  instruments  now  known  to  exist  are 
preserved  in  the  Tribuna  di  Galileo,  Florence.  The  lenses  are  missing,  and  the 
genuineness  of  the  tubes  themselves  is  doubtful.  For  much  interesting  informa- 
tion on  this  subject  see  Prof.  Govi's  '  The  Compound  Microscope  invented  by 
Galileo ',  in  Journal  of  the  Royal  Microscopical  Society,  1889,  pp.  574  et  seq.,  and 
the  two  articles  by  Charles  Singer  quoted  above. 

^  Cf .  Nat.  Ed.,  vol.  iii,  Part  1,  passim  ;  vol.  x,  pp.  273,  410  ;  vol.  xix,  pp.  229, 
610. 

i        Q  2 


T,V1  W'lIK   SCIKXTIIK     WOl'vKS   OF  GALK.KO 

Imiiinous  bodies,  jind  tlic  .scintillation  ol  tlic  fixed  stai>>,  which 
dilTcrciitiatcd  them  from  the  planets.  Upon  directing  the  telesco})c 
to  the  more  consj)icuons  star-elusters,  he  was  astonished  to  find 
tliat  they  contained  a  j^reat  num})er  of  other  stars  too  faint  to  he 
recognized  by  the  naked  eye.  Thus,  the  numlx-r  of  the  Pleiades, 
from  six  or  seven,  now  rose  to  tliirty-six  ;  while  in  Orion,  instead 
of  thirty-seven,  he  now  counted  as  many  as  eighty  stars.  Next, 
examining  portions  of  the  Pvlilky  Way  and  other  nebulous  patches 
he  resolved  them  into  congeries  of  stars  of  various  magnitudes. 
Tiuning  to  the  moon,  he  brought  it  to  a  distance  of  less  than  three 
semi-diameters  of  the  earth,  making  it  appear  about  twenty 
times  nearer  and  four  hundred  times  larger  than  when  seen  by 
the  nnaided  eye. 

Early  in  January,  1610,  Galileo  had  constructed  a  still  more 
powerful  telescope,  which  showed  objects  more  than  thirty  times 
nearer  and  nearly  one  thousand  times  larger.  With  this  instru- 
ment he  not  only  verified  and  completed  the  observations  begun 
the  previous  autumn  with  his  fourth  telescope,  but  he  also  dis- 
covered Jupiter's  moons. 

Writing  to  a  friend  at  the  Tuscan  Court  on  30th  January, 
1610,  he  thus  alludes  to  this  series  of  discoveries  : 

'  I  give  thanks  to  God,  who  has  been  pleased  to  make  me 
the  first  observer  of  marvellous  things  unrevealed  to  bygone 
ages.  I  had  already  ascertained  that  the  moon  was  a  body  very 
similar  to  the  earth,  and  ^lad  shown  our  8erene  Master,  the  Grand 
Duke,  as  much,  but  imperfectly,  not  then  having  such  an  excellent 
spy-glass  as  I  now  possess,  which,  besides  shov/ing  the  moon  most 
clearly,  has  revealed  to  me  a  multitude  of  fixed  stars  never  before 
seen,  being  more  than  ten  times  the  number  of  those  that  can  be 
seen  by  the  unaided  eye.  Moreover,  I  have  ascertained  what  has 
al\^-ays  been  a  matter  of  controversy  among  philosophers,  namely, 
the  nature  of  the  Milky  Way.  But  the  greatest  marvel  of  all  is 
the  discover}'  of  four  new  planets.  I  have  observed  their  motions 
proper  to  themselves  and  in  relation  to  each  other,  and  wherein 
they  differ  from  the  motions  of  the  other  planets.  These  new  bodies 
move  round  another  very  great  star,  in  the  same  way  as  Mercury 
and  ^^nus,  and,  peradventure,  the  other  known  planets,  move 
round  the  sun.  As  soon  as  my  tract  is  printed,  ...  I  shall  send 
a  copy  to  his  Highness,  the  Grand  Duke.' 

Tliis  tract  is  the  Sidereus  Nunciu-s,  the  preface  of  which  is 
dated  4th  March,  1610.  In  this  epoch-marking  treatise  he  gives 
the  results  of  his  observations.  He  speaks  first  of  the  moon. 
The  discovery  of  spots,  added  to  those  already  visible  to  the 
naked  eye,  and  observations  on  the  changes  of  light  on  those 


THE  SCIENTIFIC  WORKS  OF  GALILEO  233 

spots,  led  him  to  the  conclusion  that  the  surface  of  the  moon,  far 
from  being  smooth  and  polished  according  to  the  tlien  accepted 
opinion,  was  rough  with  deep  depressions  and  high  mountains. 
The  brilliant  parts  he  inferred  Avere  land,  while  those  which 
remained  obscure — the  permanent  spots — he  regarded  as  water. 
The  illuminated  edges  of  the  moon  showed  themselves  smooth 
and  without  those  indentations  which  one  would  expect  from  the 
inequalities  of  the  surface.  Galileo  explained  this  appearance 
(1)  by  supposing  that  the  mountainous  parts  masked  each  other 
as  it  were,  so  that  at  the  distance  of  the  earth  the  intervening 
depressions  were  not  discernible,  and  (2)  by  the  existence  of  a  lunar 
atmosphere  of  a  density  such  as  to  reflect  the  solar  rays  while  not 
obstructing  the  vision.  From  the  appearance  of  illuminated 
mountain-tops  in  the  dark  part  of  the  moon,  at  some  little  cUstancc 
from  the  broken  line  along  which  sumise  or  sunset  was  general, 
he  was  able  to  judge  of  the  height  of  some  of  the  mountains, 
and  his  calculation  agrees  very  well  with  the  modern  estimate. 
The  higher  mountains  were  found  to  rise  four  or  five  miles  above 
the  general  level. 

Gahleo  remarked  the  feeble  hght,^  which,  in  the  first  and  last 
quarters  of  the  moon,  makes  visible  to  us  that  part  of  its  chsk 
which  is  no  longer  illuminated  directly  by  the  sun.  After  showing 
that  the  light  did  not  originate  in  the  moon  itself,  that  it  was  not 
caused  by  sunhght  passing  through  its  body,  that  it  was  not 
reflected  there  from  Venus,  he  concludes  that  it  can  only  be  due 
to  the  sunlight  reflected  from  the  earth  to  the  moon,  and  thence 
reflected  back  to  our  eyes.  He  contended  therefore  that  our  earth 
shines,  like  the  moon  and  planets,  by  light  from  the  sun  ;  that  it 
far  exceeds  the  moon  in  luminosity  ;  and  that  since  it  is  a  moving 
planet  it  is  thus  fully  comparable  to  the  other  heavenly  bodies. 

In  using  the  telescope  to  examine  the  fixed  stars  and  comparing 
them  with  the  planets,  Galileo  observed  a  remarkable  difterence. 
While  the  planets  showed  themselves  as  disks,  like  little  moons, 
the  stars  appeared  but  little  larger  than  with  the  naked  eye,  just 
bright  specks  sending  forth  twinkling  rays.  He  explained  this 
apparent  failure  of  the  telescope  to  enlarge  in  proportion  to  its 
magnifying  power  as  due  to  the  effect  of  irradiation.     In   virtue 

^  Now  known  as  earthshine.  Previously  noticed  by  Pythagoras  (c.  580-504 
B.C.),  by  Plato  (428-347  B.C.),  and  by  Leonardo  da  Vinci  (1452-1519).  In  1640 
Fortunio  Liceti  held  that  the  moon  is  a  phosphorescent  body  like  the  Bologna 
Stone.  This  drew  from  Galileo  a  reply — his  last  great  effort.  See  Xat.  Ed.;  vol. 
viii,  pp.  467-556. 


234  TUK  SCMKNTIKIC   WORKS  OF  GALILEO 

of  tluH  piiiicij)k*,  a  lij^lit  [)rojectcd  upon  a  dark  <4r<)Uiid  is  dilated 
in  all  directioiiH,  ko  as  to  appear  larger  than  it  really  is,  and  the 
greater  its  imninosity  the  greater  is  the  irradiation,  and  the  larger 
tlie  light  a|)pcars  to  he.  A  star,  then,  as  seen  l)y  the  naked  eye 
is  a  huniiious  point  j)lus  its  dilated  corona.  Now,  the  telescope 
has  the  property  of  cancelling  or  masking,  more  or  less  according 
to  the  degree  of  luminosity,  this  false  light,  so  that  what  we  see 
is  the  resultant  of  two  opposite  effects,  (1)  the  star  bereft  more 
or  less  of  its  corona,  and  (2)  the  star  as  enlarged  by  the  power 
of  the  glass  ;  and,  since  the  resultant  enlargement  is  but  little, 
we  must  conclude,  -not  that  the  telescope  fails  in  such  cases,  but 
that  the  corona,  though  diminished,  is  still  able  to  nearly  counter- 
balance the  telescopic  enlargement,  with  the  result  that  the 
apparent  size  is  little  larger  than  that  exhibited  to  the  naked  eye.'^ 

When  Galileo  turned  his  fourth  telescope  to  the  planets  he 
saw  them  as  little  moons.  Jupiter's  disk  was  of  considerable  size, 
but  in  no  other  way  did  he  differ  from  the  other  planets.  Now, 
on  the  7th  of  January,  1610,  directing  his  fifth  and  more  powerful 
glass  towards  Jupiter,  his  attention  was  drawn  to  three  small  but 
bright  stars  in  his  vicinity,  two  on  the  east  side  and  one  on  the 
west.  He  at  first  imagined  them  to  be  fixed  stars,  and  yet  there 
was  something  in  their  appearance  w^hich  he  thought  curious,  and 
they  were  all  disposed  in  a  right  line  parallel  to  the  plane  of  the 
ecliptic.  Happening,  by  mere  accident,  as  he  says,  to  examine 
Jupiter  again  on  the  next  night,  he  was  surprised  to  find  these 
stars  now  arranged  quite  differently.  They  were  all  on  the  west 
side,  nearer  to  each  other  than  on  the  previous  evening,  and  at 
equal  distances  apart.  He  therefore  waited  for  the  following  night 
with  some  anxiety,  but  he  was  disappointed,  for  the  heavens  were 
enveloped  in  clouds.  On  the  10th  of  January  he  could  see  only 
two  stars,  and  they  were  both  on  the  east  side  !  He  suspected 
that  the  third  might  be  concealed  behind  the  disk  of  the  planet. 
Those  visible  appeared  as  before  in  the  same  right  line,  and  lay 
in  the  direction  of  the  ecliptic.  Unable  to  account  for  such  changes 
by  the  motion  of  the  planet,  and  being  fully  assured  that  he 
always  observed  the  same  stars,  he  concluded  that  the  motions 
must  be  referred  to  the  stars  themselves  and  not  to  the  planet. 

On  the  11th  of  January  he  again  saw  only  two  stars,  still  on 
the  east  side,  but  the  outer  one  was  now  nearly  twice  as  large 

^  He  has  a  great  deal  more  on  this  subject  in  his  letters  to  Griemberger  on 
Lunar  Mountains,  in  his  works  on  Sun-spots,  and  in  //  Saggiatore,  which  see  infra. 
Irradiation  was  first  treated  as  a  general  principle  by  Kepler  in  1604. 


THE  SCIENTIFIC  WORKS  OF  GALILEO  235 

as  the  other,  although  on  the  previous  night  they  were  almost 
equal.  This  fact,  taken  in  connexion  with  the  constant  change 
of  the  relative  positions  of  the  stars,  and  the  total  disappearance 
of  one  of  them,  now  revealed  to  him  their  real  character.  He 
concluded  that  there  are  in  the  heavens  three  stars  revolving 
round  Jupiter  in  the  same  way  as  Venus  and  Mercury  revolve 
round  the  sun.  On  the  12th  of  January  he  again  saw  three  stars, 
two  on  the  east  side,  and  one  on  the  west.  The  third  began  to 
appear  about  three  o'clock  in  the  morning,  emerging  from  the 
eastern  limb  of  the  planet  ;  it  was  then  very  small,  and  discernible 
only  with  great  difficulty.  On  the  13th  of  January  he  saw  four 
stars,  three  on  the  west  side  and  one  on  the  east.  They  were  all 
in  a  line  parallel  to  the  ecliptic,  with  the  exception  of  the  central 
one  of  the  western  group,  which  was  a  little  towards  the  north. 
They  were  all  about  the  same  size,  and  shone  with  a  much  greater 
lustre  than  fixed  stars  of  the  same  magnitude.  January  the  14tli 
was  cloudy,  but  next  night  he  saw  all  four  stars  to  the  west  of 
the  planet,  all  nearly  in  the  same  right  line,  and  increasing  in 
size  and  brilliancy,  according  to  their  distance  from  Jupiter.  And 
so  he  continued  nightly,  up  to  the  2nd  of  March,  1610,  to  make 
these  observations,  sixty-six  of  which  are  figured  and  described 
in  the  Sidereus  Nuncius} 

The  persistence  of  the  relative  distances  between  these  four 
bodies  and  Jupiter  in  all  their  changes  left  no  room  for  doubt 
that  they  accomplished  with  him,  and  in  about  twelve  years, 
a  revolution  around  the  sun  as  a  centre.  Their  own  orbits  round 
the  planet  were  unequal  in  time,  those  nearest  moving  more 
rapidly  than  those  more  remote  ;  while  the  most  remote  of  all 
appeared  to  complete  its  revolution  in  about  fifteen  days. 

During  the  Easter  recess  of  1610  at  Padua,  Galileo  had  an 
express  invitation  from  the  Tuscan  Court,  then  at  Pisa,  to  explain 
to  the  Grand  Duke  his  discovery  of  the  four  satellites  of  Jupiter, 
which,  in  honour  of  the  reigning  family,  he  proposed  to  call  Medicean 
Stars,  after  the  four  brothers  Cosimo  II,  Francesco,  Carlo,  and 
Lorenzo.  Cosimo  II,  who  all  his  life  showed  a  sincere  attachment 
to  his  tutor,  asked  for  and  obtained  the  gift  of  the  instrument 
with  which  this  discovery  was  made  ;  but  Galileo  quickly  repented 
of  his  generosity.     He  evidently  could  not  part  with  his   '  old 

^  There  are  also  (1)  Diagram  to  illustrate  principle  of  the  telescope,  (2)  five 
drawings  of  the  moon's  superficies,  (3)  two  diagrams  on  lunar  measurements 
(4)  Orion,  (5)  Pleiades,  (6)  Nebulosa  Orionis,  and  (7)  Nebulosa  Praesepe. 


236  THK  S(!IKXTIFIC  WORKS   OF  GALILEO 

discoveivr  ',  as  ho  alkHtioiiatcIy  called  it  in  after  years  ;  so,  while 
always  reserving  it  lor  the  Grand  Duke,  he  kej)t  it  near  himself 
till  his  death,  when  it  was  handed  over  to  Prince  l^oj>oldo,  brother 
ot   lu^rdiiiaiulo  1 1. 

Of  its  suhsequcnt  history  little  is  knowji  with  certainty.  It 
would  appear  that  in  (lahleo's  last  years  the  instrument  was  acci- 
dentally broken.  'I'hen,  in  1675,  there  is  a  record  in  the  inventory 
of  the  effects  of  ( "ardinal  Leopoldo  de'  Medici  of  a  '  broken  object- 
glass  with  which  Galileo  discovered  the  four  new  ])lanets  '  ;  and 
in  1077  another  record  of  its  having  been  set  in  an  ivory  frame. 
It  is  now  preserved,  together  with  two  telescopes,  said  to  have 
been  made  by  Galileo,  and  certainly  of  his  time,  in  the  Tribuna 
di  Galileo  at  Florence,  with  many  other  precious  rehcs  of  the 
period.  Accurate  measurements  of  it  have  been  made  quite 
recently  by  Professor  Roiti  of  the  University  of  Florence,  as 
follows:  Focal  distance  1-70  metres,  diameter  0056  metre.  One 
face  has  the  curvature  of  a  sphere  with  radius  of  0  935  metre,  and 
the  other  face  is  practically  plane,  having  just  a  trace  of  convexity.^ 

12.  On  Saturn  - 
After  completing  his  study  of  Jupiter,  Galileo  turned  his  glass 
to  the  other  planets  to  see  if  they  also  had  attendant  moons. 
On  the  25th  of  July,  1610,  he  was  rewarded  by  another  bril- 
liant discovery — the  phenomenon  that  we  now  describe  as  the 
ring  of  Saturn.  To  liim,  how^ever,  it  did  not  appear  as  a  ring, 
but  as  a  triple  star  of  which  the  central  part  was  about  three 
times  larger  than  the  laterals,  and  all  three  almost  touching,  and 
in  a  plane  parallel  to  the  zodiac.  He  made  further  observations 
in  the  autumn,  when  Saturn  was  well  above  the  horizon,  and, 
fearing  that  some  one  might  forestall  him,  he  announced  the 
discovery  in  a  brief  letter,  dated  Padua,  30th  July,  1610,  to 
Behsario  Vinta,  at  Florence,  but  begged  him  to  keep  it  secret  for 
a  while.  As  a  further  precaution  lest  his  claims  should  be  fore- 
stalled he  sent  to  friends  in  Italy  and  Germany  a  cryptogram  of 
thirty-seven  letters  as  follows  : 

SMAISMRMILMEPOETALEUMIB\T^ENUGTTAVIRAS 
Kepler  and  other  friends  puzzled  long  over  this  anagram,  the 
former  thinking  it  had  some  reference  to  his  favourite  planet 

^  Cf.  Favaro's  Intorno  ai  Cannocchiali  costruiti  ed  usati  da  Galileo,  Venezia, 
1901.  ^  Cf.  Nat.  Ed.,  vol.  x,  pp.  410,  474  ;   xi,  p.  439  ;  xviii,  p.  238. 


f 


THE  SCIENTIFIC  WORKS   OF  GALILEO  237 

Mars.  At  length,  Giuliano  de'  Medici,  Tuscan  ambassador  at  the 
German  Court,  was  charged  by  the  Emperor  Rudolph  II  to  ask 
for  the  solution,  to  whom  Gahleo,  replying  13th  November,  1610, 
gave  the  following  startling  solution  : 

'  Altissimum  Planetam  Tergeminum  Observavi.' 

'  I  have  observed ',  he  says,  '  with  great  admiration  that  Saturn 
is  not  a  single  star  but  three  together,  which,  as  it  were,  toucli 
each  other.  They  have  no  relative  motion,  and  are  constituted 
in  this  form  [see  Fig.  7,  i],  the  middle  being  much  larger  than 
the  lateral  ones.  They  are  not  strictly  in  the  line  of  the  zodiac, 
but  rather  parallel  to  the  equinoctial  line.  ...  I  have  already 
discovered  a  court  for  Jupiter,  and  now  there  are  two  attendants 
for  this  old  man,  who  aid  his  steps  and  never  leave  his  side.' 

The  learned  world  had  not  yet  had  time  to  digest  the  surprising 
facts  announced  in  the  Sidereus  Nuncius,  when  this  asserted  triple 
nature  of  Saturn  again  contravened  the  prevailing  Aristotehan 
ideas.  Continuing  his  observations,  Galileo  found  that  the  lateral 
bodies  did  not  retain  the  same  apparent  magnitudes.  In  fact, 
they  had  been  gradually  diminishing,  although  they  appeared  to 
be  immovable,  both  with  respect  to  each  other  and  to  the  central 
body.  They  continued  to  grow  less  and  less  during  the  next  two 
years,  and  towards  the  close  of  1612  they  vanished  altogether  ! 
Horrified  at  this  extraordinary  phenomenon,  and  full  of  alarm  for 
the  consequences  to  himself  when  his  Aristotelian  opponents 
should  come  to  hear  of  it,  he  thus  wTote  to  Welser  on  December 
1st,  1612  : 

'  Looking  at  Saturn  within  these  last  few  days,  I  found  it 
sohtary  without  its  accustomed  stars,  and,  in  short,  perfectly 
round  and  defined  like  Jupiter,  and  such  it  still  remains  !  Now 
what  can  be  said  of  so  strange  a  metamorphosis  ?  Are,  perhaps, 
the  two  smaller  stars  consumed  like  spots  on  the  sun  ?  Have 
they  suddenly  vanished  and  fled  ?  Or  has  Saturn  devoured  his 
own  cMldren  ?  Or  was  the  appearance,  indeed,  fraud  and  illusion, 
with  which  the  glasses  have  for  so  long  mocked  me  and  many 
others  who  have  observed  with  me  ?  ' 

He  continued,  however,  to  conjecture  that  the  two  attendant 
stars  would  reappear  after  revolving  with  the  planet,  and  that, 
by  the  summer  solstice  of  1615,  they  would  be  not  only  again 
visible,  but  more  luminous  and  larger.  And  by  the  middle  of 
1615  he  was  able  to  verify  his  prediction,  for  the  lateral  stars 
were  now  reappearing  (Fig.  7). 


2:w 


THK  SCIENTIFIC   WORKS   OK  CALILEO 


No  change  cailiii*^;  for  special  commont  was  noticeable  until 
the  summer  of  1616,  when  he  made  a  new  observation  relating  to 
Saturn,  in  August  of  that  year,  writing  to  l*rince  Cesi,  Galileo 
says  : 

'  I  cannot  rest  without  signifying  to  your  Excellency  a  new 
and  most  strange  j)henomenon  observed  by  me  in  the  last  few 
days  in  Saturn.  Its  two  companions  arc  no  longer  two  small 
and  ])erfectly  round  globes,  as  they  have  hitherto  aj)f)eared  to 
be,  but  are  now  bodies  much  larger,  and  of  a  form  no  longer 
round,  but,  as  shown  in  the  annexed  figure  (see  Fig.  7,  iii),  with 

the  two  middle  parts  obscured, 
that  is  to  say,  the  very  dark 
triangular-like  spaces  contiguous 
to  the  middle  line  of  Saturn's 
globe,  which  latter  is  seen,  as 
always,  perfectly  round.'  ^ 

Up  to  the  last,  Galileo  made 
no  announcement  as  to  the  precise 
nature  of  Saturn's  appendages. 
He  contented  himself  with  de- 
scribing what  he  saw,  and,  re- 
cognizing the  incompleteness  of 
his  knowledge,  and,  perhaps,  the 
Fig.  7.  EARLY  DRAWINGS  OF  inadequate  power  of  his  glass,  he 
SATURN  igf^  -^  ^Q  ^j^g  future  to  solve  the 

From  the  Sustema  Satumum.  ,  ,  mi  •  j  i 

problem.  This  was  done  by 
Christian  Huygens  in  1655.  Working  with  a  refracting  telescope, 
magnifying  100  diameters,  this  astronomer  not  only  saw  and 
described  the  ring  as  a  ring,  but  discovered  one  of  Saturn's 
satellites. 

13.  Venus,  Mercury,  and  Mars  ^ 
These  discoveries  stimulated  yet  further  the  interest  of  GaUleo's 
grand-ducal  pupil,  and  in  June  1610  Cosimo  II  nominated  him 
'  First  Mathematician  of  the  University  of  Pisa,  and  First  Mathe- 
matician and  Pliilosopher  to  the  Grand  Duke  '.  Galileo  now 
returned  to  Florence.  Here,  on  September  30,  he  made  another 
astounding    discovery   in   the    heavens,    namely,    the    occasional 

^  Cf .  Favaro,  '  Intorno  all'  Apparenza  di  Saturno  osservata  da  Galileo  nel- 
TAgosto  1616  '  {Atti  del  Beale  Istituto  Veneto,  February,  1901). 
2  Cf.  Nat.  Ed.,  vol.  x,  pp.  483,  499,  503  ;   vol.  xi,  pp.  11-12. 


i 


THE  SCIENTIFIC  WORKS   OF  GALILEO  239 

crescent  form  of  the  planet  Venus.  After  satisfying  himself,  by- 
three  months'  observations,  of  its  correctness,  he  announced  the 
fact  in  a  letter  (11th  December)  to  his  friend  GiuHano  de'  Medici 
at  Prague,  but  concealed  it  again  in  an  anagram  as  follows  : 
'  Haec  immatura  a  me  iam  frustra  leguntur  o  y.'  He  did  not, 
however,  leave  his  friend  long  in  perplexity,  for  on  the  1st  of 
January,  1611,  he  sent  him  the  solution  :  '  Cynthae  figuras  aemu- 
latur  mater  amorum.'  '  That  is,  Venus  rivals  the  appearance  of 
the  moon  ;  for,  being  now  arrived  at  that  point  of  her  orbit  in 
wliich  she  is  between  the  earth  and  the  sun,  and  with  only  a  part 
of  her  enhghtened  surface  turned  towards  us,  the  telescope  shows 
her  in  a  crescent  form,  like  the  moon  in  a  similar  position.' 
Following  her  through  the  visible  portion  of  her  orbit,  he  had  the 
satisfaction  of  seeing  the  illuminated  part  assume  successively  the 
crescent  forms  appropriate  to  his  hypothesis. 

It  was  with  reason,  therefore,  that  he  laid  stress  on  the  impor- 
tance of  these  observations,  which  established  yet  another  fact 
obnoxious  to  the  Aristotelians — a  further  resemblance  between 
the  earth  and  moon  and  one  of  the  principal  planets.  As  he  had 
shown  in  Sidereus  Nuncius  that  the  earth,  like  the  moon,  is 
luminous  only  where  exposed  to  the  sun's  rays,  so  tliis  change 
of  figure  in  Venus  demonstrated  that  she  and,  probably,  all  the 
other  planets  were  not  luminous  of  themselves,  but  reflected  the 
sun's  Hght.  Thence  he  concluded  that  they  must  all  revolve 
round  the  sun — '  a  fact  surmised  by  Pythagoras,  Copernicus, 
Kepler,  and  their  disciples,  but  that  could  not  be  proved  by 
ocular  demonstrations  '.  For  it  had  always  been  a  formidable 
objection  to  the  Copernican  theory  that  Venus  and  Mercury  did 
not  exhibit  the  same  phases  as  the  moon,  which  they  should  do 
if  they  revolved  round  the  sun,  and  Copernicus  himself  had 
endeavoured  to  account  for  this  by  supposing  that  the  sun's  rays 
passed  freely  through  the  body  of  the  planets. 

Of  similar  changes  in  Mercury,  the  existence  of  which  he 
inferred  by  analogy,  he  could  observe  nothing,  because  that 
planet's  orbit  does  not  take  him  far  from  the  sun,  and,  in  con- 
sequence, his  small  disk  is  always  so  resplendent  that  not  even 
the  best  telescope  could  deprive  him  of  his  factitious  rays.^ 

^  The  revolution  of  Mercury  about  the  sun,  which  Galileo  assumed,  was  con- 
firmed twenty  years  later.  Just  before  his  death  in  1630,  Kepler  predicted  a  transit 
of  Mercury  for  the  next  year,  and  it  was  duly  observed,  on  November  7,  1631, 


240  rHK  SCIKNTIFK!   WOHKS   OK  (JALILKO 

Tho  orbit  of  Mais  being  exterior  to  that  of  th(i  eartl),  ho  is 
not  subject  to  phases  like  tlio  inferior  |)laiietH  Venus  and  Mercury, 
but  in  certain  positions  ho  assumes  a  gibbous  ai)pearance,  like 
that  of  tlie  moon  a  little  before^  and  after  the  full.  (;!alileo  recog- 
nized this  feature,  and,  after  lour  months'  careful  observation,  ho 
announced  that  '  when  Mars  is  in  quadrature,  or  the  middle  points 
of  his  path  on  each  side  of  the  sun,  his  figure  varies  slightly  from 
a  perfect  circle.  I  dare  not  allirm  that  1  can  observe  phases,  but, 
if  I  mistake  not,  i  already  perceive  that  he  is  not  always  perfectly 
round.'  ,He  also  observed  that  the  apparent  size  of  the  planet 
varied  according  to  its  distance  from  tlio  sun,  being  sixty  times 
larger  when  in  opposition  than  when  in  conjunction. 


14.  On  Sun- Spots  ^ 

In  consideration  of  the  intense  interest,  friendly  and  otherwise, 
excited  by  these  discoveries  in  Rome,  Galileo  thought  it  desirable 
to  go  there  himself,  and  acquaint  at  first  hand  the  savants  and 
dignitaries  of  the  Church  with  his  work.  It  was  not  till  March 
23,  1611,  that  he  w-as  able  to  set  out,  provided  with  many 
letters  of  introduction,  amongst  them  one  from  Michelangelo  the 
younger  (nephew  of  the  great  sculptor  and  painter)  to  Cardinal 
Barberini  (afterwards  Pope  Urban  VIII).  He  was  received  with 
distinction  by  princes  and  all  the  Church  dignitaries,  as  well  as 
by  the  learned  lajaiien.  Even  those  w  ho  discredited  his  discoveries, 
either  through  obstinacy  or  through  fear  of  their  results,  were  as 
eager  as  the  true  friends  of  science  to  see  and  hear  this  wonder 
of  the  age. 

After  exhibiting  on  several  occasions  all  his  recent  discoveries, 
or  '  celestial  novelties  '  as  they  w^ere  called,  a  commission  of  four 
scientific  members  of  the  Roman  College  was  appointed  to  examine 
them.  Their  report  of  April  24  was  favourable  on  all  points,  and 
was  considered  as  equivalent  to  an  official  Imprimatur.  Pope 
Paul  V  granted  him  a  long  audience,  and  assured  him  of  his 
unalterable  goodwill ;  high  dignitaries  of  the  Church  followed  suit, 
and  the  Accademia  dei  Lincei  elected  him  a  member. 

ImmecMately  after  the  publication  of  the  report  of  the  com- 

by  Gassendi,  who  followed  Kepler's  instructions.    Our  own  countryman,  Horrocks, 
was  the  first  to  observe  a  transit  of  Venus,  in  1639. 

1  Cf.  Xat.  Ed.,  vol.  V,  pp.  10-260  ;   vol.  vii,  p.  372  ;   vol.  xiv,  p.  299. 


4 


S  I  D  E  R  E  V  S 

N  V  NC I  V  S 

MAGNA,  LONGEQ.VE   ADMIRABILIA 

Spedacula  panden; ,  fulpiciendi^"'  propoaens 
vnicuique,  przfertim  veto 

VHILOSOPHIS  ■,   Atj^  ASTRONOM  IS.^atl 

GALILEO   GALILEO 

P  ATR  ITIO  FLORENTINO 

Patauini  Gymnafij  Publico  Mathemacico 

PERSPICILLI 

^t^tr  dfe  referti  beneficiofmt  obferuata  in  LyT>^y£  F^CTly  FfXlS  rt^ 

HyMEBJSi  L4CTE0  CIf{CyLOy  ST  EL  LIS  TiLBVLOSlSy 

c^pfrime  "Per 6  :n 

QJ/  ATVOK    PLANETIS 

Circa  TO  V  I  S  Siellam  difparibus  mterualbs,  aique  pcnodis, eden- 
tate roirabifi  circumuolutis-,  qaos  «  ncroiuiin  hancvr<jue 
<ii€ni  cognicos,  nomninie  Aathor  dcprx- 
hendic  primus,  atque 

MEDICEA  SIDERA 

NVNCVPANCrOS    DECREVIT. 


VHKETilS,  ApudThomam  Bagiionum,   M    PC    X. 


Fig.  8.     Title-page  of  Sidereu.s  Nuncius. 


242  INK   S('lb:N'riFI('    WORKS   OF  (MLILEO 

mission,  (Jalilco  announced  yet  anotlK^r  new  diHcovery  in  the 
heavens,  namely,  dark  sj)otH  on  tli(^  hody  of  the  sun,  whieli, 
towards  the  end  of  April  1611,  he  showed  to  .several  prelates  and 
men  of  seienee  in  Home.  Deserihing  these  plnuiomena,^  he  states 
that  at  first  he  \n  as  undecided  whether  to  explain  the  ever-ehanging 
form  and  |)osition  of  the  spots  by  sui)posing  that  tlu^  sun  revolved, 
or  by  imagining  that  other  and  hitherto  unknown  planets  revolved 
about  the  sun,  and  were  visible  only  as  spots  on  his  disk.  Further 
observation,  however,  led  him  to  abandon  the  latter  supposition 
and  to  announee  positively  that  the  spots  were  in  eontact  with 
the  body  of  the  sun,  where  they  were  eontinually  ay)pearing  and 
disappearing  much  as  elouds  about  our  earth.  These  observations 
were,  in  their  consequences  to  Galileo,  particularly  unfortunate, 
as  he  thereby  became  embroiled  with  the  powerful  Jesuit  party 
whose  influence  was  one  of  the  chief  causes  of  his  subsequent 
misfortunes. 

A  Jesuit  father,  Christopher  Scheiner,  Professor  of  Mathematics 
at  Ingolstadt,  claimed  priority  in  the  discovery  of  the  sun-spots, 
asserting  that  early  in  1611  he  first  noticed  them  and  showed 
them  to  his  pupils.  Scheiner  stated  his  case  in  three  open  letters 
addressed  to  Mark  Welser,  Chief  Magistrate  of  Augsburg,  though 
it  is  clear  from  these  letters  that  at  first  he  attached  no  importance 
to  these  appearances,  and  even  thought  them  due  to  defects  in 
his  glasses.  The  spots  he  supposed  to  be  caused  by  multitudes 
of  little  planets,  revolving  round  the  sun  in  an  orbit  inside  Mercury, 
and  producing  the  appearance  of  spots  in  crossing  Ms  disk. 

On  the  publication  of  Scheiner's  letters,  Welser  sent  a  copy 
to  Gahleo,  requesting  to  be  favoured  with  his  opinions  of  the 
phenomena  therein  described.  He  repHed  in  three  letters  dated 
respectively  4th  May,  14th  August,  and  1st  December,  1612.  In 
the  first  letter  (the  autograph  copy  of  which  is  now  in  the  British 
Museum)  he  begins  by  saying  that  the  phenomena  are  not  illusions 
produced  by  the  glasses,  but  veritable  facts,  which  he  himself  had 
observed  eighteen  months  before  in  Florence,  and  which  he  had 
shown  to  many  people  in  Rome  in  April  of  the  past  yea,T.'-     He 

^  Discourse  on  Floating  Bodies,  1612,  which  see  infra,  p.  249. 

2  At  the  end  of  II  Saggiatore  (1623),  and  in  the  Dialogue  of  1632  (3rd  Day), 
he  states  that  he  first  observed  the  spots  while  still  in  Padua,  and  that  he  showed 
them  to  some  friends.  This  would  take  the  date  back  to  the  summer  of  1610. 
The  claim  is  supported  by  Fulgenzio  Micanzio  and  Viviani.    Galileo  explains  his 


THE  SCIENTIFIC  WORKS   OF  GALILEO  243 

then  proceeds  to  combat  Scheiner's  various  and  often  contradictory 
assertions  as  to  the  nature  of  the  spots,  and  their  places  and 
movements  in  relation  to  the  body  of  the  sun. 

'  I  would  say ',  he  writes,  '  that  they  are  formed  on  the  sun's 
superficies,  that  they  are  carried  round  with  him  in  his  rotation, 
remaining  visible  for  about  one-half  month  ;  and  that  they  may 
be  something  of  the  nature  of  our  own  clouds.  Certainly,  if  our 
earth  were  self-luminous  and  surrounded  by  clouds,  it  would  seem 
to  a  far-distant  observer  to  have  spots  like  those  we  see  on  the 
sun,  now  uniting,  now  separating,  and  now  dissolving.  They 
would  follow  her  in  her  rotation,  appearing  very  large  at  the 
centre  of  her  disk,  where  their  motion  would  be  most  rapid,  and 
contracting  towards  the  edges,  where  they  would  be  smallest,  and 
where  also  their  velocity  would  be  least.' 

This  he  recognized  as  an  effect  of  fore-shortening  which  would 
result  if,  and  only  if,  the  spots  were  on  or  very  near  the  sun. 

In  the  second  letter  he  restates  his  views,  adding  some  further 
particulars  as  to  the  constant,  slow,  and  irregular  changes  in  the 
form  of  the  spots,  and  their  varying  density,  being  very  dark  at 
the  centre,  and  less  so  towards  the  circumference — '  a  manifest 
proof  of  the  sun's  sphericity  '.  They  are  confined  to  a  zone  about 
the  sun's  equator,  extending  28  or  29  degrees  (in  his  third  letter 
he  says  29  or  30)  on  each  side,  beyond  which  they  are  never  seen  ; 
and,  finally,  they  all  have  a  common  motion  of  rotation.  From 
all  these  facts,  and  from  the  additional  one,  that  often  the  same 
spot  disappearing  at  one  side  reappears  at  the  other,  he  concludes 
that  the  sun  is  a  sphere,  that  it  rotates  on  its  axis  from  west  to 
east,  and  that  it  performs  one  such  rotation  in  about  a  lunar 
month.  In  an  appendix  he  gives  forty  sketches  of  spots  as  observed 
from  day  to  day  during  June,  July,  and  August,  1612. 

In  his  third  letter,  dated  1st  December,  1612,  Galileo  notices 
some  observations  of  Scheiner  on  Venus  and  the  moon,  and  shows 
the  falsity  of  his  '  facts  '  and  deductions  ;  he  recurs  to  the  sun- 
spots  and  adduces  a  further  proof  of  the  correctness  of  his  own 
hypothesis  in  the  behaviour  of  some  very  bright  spots  [piazzette^ 
now  called  faculae).     Some  parts  of  the  sun's  disk  are  perceived 

silence  as  to  these  earlier  observations  thus  :  '  Having  regard  to  the  extraordinary 
nature  of  the  phenomena,  so  contrary  to  the  received  opinions,  1  judged  it  more 
prudent  to  wait  until  I  had  convincing  proof.  I  prefer  to  be  the  last  to  produce 
a  true  conception  than  to  anticipate  others  at  the  risk  of  having  to  unsay  what 
I  was  in  a  hurry  to  affirm  '  (Nat.  Ed.,  vol.  v,  p.  94). 


244  THE  SC'IEXTiriC   WORKS   OF  OALILI^X) 

to  !)('  I)riti5ht('r  lluin  tlir  icsl,  and  tliCHC  parts  appear  to  traverHe 
the  disk  just  as  tlic  other  spots  do.  Now,  were  these  very  bright 
spots  j)lanets,  as  Scheiner  would  have  it,  they  ought  Hometimes 
to  appear  beyond  the  sun's  limb,  but  tliis  tliey  never  do — an 
irrefragable  |)n)of  that  they  are  j)art  and  parcel  of  the  sun  himself. 

AftiM-  refeiring  to  various  subjects,  as  the  inhabitability  of  the 
planets,  the  suj)posed  crystalline  and  transparent  substance  of 
the  moon,  the  diversity  of  figure  amongst  the  planets,  and  the 
periods  of  Jui)iter's  satellites  (of  which  Scheiner  had  receMly 
'  discovered  '  a  fifth),  he  returns  once  more  to  the  sun-spots  and 
their  general  resemblance  to  clouds  or  smoke.  We  can,  he  says, 
imitate  them  in  various  ways,  as,  for  instance,  by  dropping  on 
a  red-hot  iron  plate  bits  of  bitumen.  He  supposes  that  the  sun's 
light  (and  heat)  may  be  sustained  by  a  constant  suj)ply  of  new 
jyahulum,  which,  like  the  bitumen,  first  gives  off  black  smoke, 
which  we  see  as  spots.  In  a  later  letter,  23rd  March,  1615,  to 
Piero  Dini,  he  refers  to  this  idea.  '  I  suggested ',  he  says,  '  that 
these  spots  might  be  part  of  that  pabulum  (or  rather  the  debris 
of  it),  of  which,  according  to  certain  ancient  philosophers,  the 
sun  has  need  for  his  sustentation.'  ^ 

These  letters  were  ultimately  published  at  Rome  in  1613,  at 
the  expense  of  the  Accademia  dei  Lincei,  and  under  the  title 
Istoria  e  dimostrazioni  intorno  alle  macchie  solari.^ 

15.  On  LunUr  Mountains  ^ 

Soon  after  his  return  to  Florence  in  June,  1611,  Galileo  wrote 
a  series  of  letters  on  The  Inequalities  of  the  Moon's  Surface^  in 
defence  of  the  views  expressed  in  liis  Sidereus  Nuncius.  The  moon 
was  with  him  a  stock  subject  for  observation,  the  results  of  which 
he  utilized  in  his  astronomical  works,  or  communicated  in  long 
letters  to  friends,  notably  to  Griemberger  and  Gallanzoni  in  Rome, 
and  to  Welser  and  Bernegger  in  Germany.     His  last  astronomical 

^  Newton  and  BufFon  conjectured  that  comets  might  be  the  aliment  of  the 
sun,  and,  at  present,  a  nearly  similar  explanation  finds  favour,  viz.  that  streams 
of  meteoric  matter,  varying  in  volume,  are  constantly  pouring  into  the  sun  from 
the  regions  of  space.  Professor  Turner  of  Oxford  is  the  latest  exponent  of  this 
hypothesis.  See  his  paper  in  Monthly  Notices  of  R.A.S.,  December,  1913.  Cf. 
Mayer,  Beitrdge  zur  Dynamik  des  Himmels,  Heilbronn,  1848. 

-  Nat.  Ed.,  vol.  V,  pp.  75-260. 

3  Cf.  Nat.  Ed.,  vol.  iii,  pp.  301,  313  ;   x,  pp.  461,  466  ;   xi,  pp.  141,  178. 


THE  SCIENTIFIC  WORKS  OF  GALILEO 


245 


discovery,  towards  the  close  of  life  and  just  before  he  became 
blind,  was  connected  with  the  moon. 

It  had  been  asserted  that,  as  the  full  moon  always  presented 
a  well-defined  outline,  whether  viewed  with  the  naked  eye  or 
through  a  telescope,  it  was  impossible  that  there  could  exist  any 
inequalities  around  her  circumference.  Galileo  maintained  that 
the  irradiation  of  the  moon's  light  might  be  great  enough  to  mask 
the  asperities  around  her  edge,  and  so  effectually  conceal  the  real 
nature  of  her  surface.  With  respect  to  irradiation  generally,  he 
remarked  that  it  in- 
creases with  the  bright- 
ness of  the  object.  It 
is  from  this  cause  that 
the  planets  near  the  sun 
have  a  greater  irradia- 
tion than  those  more 
remote.  So  intense  is 
the  irradiation  of  Mer- 
cury that  it  is  impossi- 
ble, even  with  the  most 
powerful  telescope,  to 
deprive  him  of  his  bril- 
liant corona.  The  same 
is  true,  though  in  a  less 
degree,  with  respect  to 
Mars.  On  the  other 
hand,  Jupiter,  and  espe- 


FiG.  9. 


The  moon  as  seen  by  Galileo,  1609-10. 
From  Sidereus  Nuncius. 


cially  Saturn,  being  more  feebly  illuminated  by  the  solar  light,  lose 
their  irradiation  in  the  telescope,  and  disclose  their  true  figures. 

With  respect  to  Venus,  when  she  is  near  her  inferior  conjunc- 
tion, she  in  reality  resembles  the  new  moon  ;  but  such  is  the 
effect  of  her  irradiation  that  she  appears  to  the  naked  eye  round 
like  any  other  star.  In  this  position,  as  the  extent  of  the  illu- 
minated surface  is  small  and  the  light  is  at  the  same  time  enfeebled 
by  the  obliquity  of  the  surface,  it  is  possible  by  means  of  a  telescope 
to  discern  the  real  crescent  appearance  of  the  planet.  When, 
however,  she  is  near  her  superior  conjunction,  she  presents  a  com- 
plete hemisphere  of  vivid  light  towards  the  earth  of  such  intensity 
that  even  the  most  perfect  telescope  does  not  reveal  to  us  her 
true   figure.     Galileo  therefore  contends  that  it  is   probable  that 


2391 


24«  IHh:   S(!IKNTIFI(;   WOJIKS   OF  GALILEO 

t'VtMi  tlio  loloscope  will  fail  to  efface  the  iiTcadiatioii  of  the  inoon 
enoiij^h  to  (liscloHC!  the  eminences  and  eavitiew  which  may  be 
situated  near  tlie  edge  of  her  disk. 

His  |)eii|)at(!tie  ()|)|)()iuuit.s  next  tried  to  reconcile  the  old 
doctrine  of  a  |)oli.slied  and  perfectly  ])lane  surface  with  these  new 
observations.  Father  (Jlavio  doubted  at  first  the  reality  of  the 
inequalities,  and  thought  that  the  appearances  were  due  to 
inequalities  in  the  reffeeting  jKiwer  of  the  moon's  substance. 
Other  Aristotelians,  as  delle  Colonibe  and  Lagalla,^  suj)posed  that 
every  2)art  of  the  moon,  which  to  us  appears  liollow,  is,  in  fact, 
filled  with  clear  crystal  matter,  thus  preserving  a  round  and 
smooth  superficies,  and  it  is  this  diversity  of  substance,  with  its 
more  or  less  transparency,  which  gives  the  impression  of  inequality 
of  fwm. 

16.  Discussion  of  Hdbitability  of  Moon  and  Planets  ^ 

Among  the  many  burning  questions  to  which  the  Sidereus 
Nuncius  gave  rise  was  that  of  whether  the  moon  and  planets 
were  inhabited.  This  was  openly  discussed  in  Rome  from  1611 
onwards,  and  its  '  manifest  absurdity  '  was  used  as  an  argument 
against  the  Copernican  theory  in  general  and  Galileo's  lunar 
observations  in  particular.  If  the  moon,  it  was  said,  is  so  like 
the  earth  with  land  and  water,  mountains  and  valleys,  and  sur- 
rounded by  an  atmosphere,  we  may  suppose  that  she  too  is  the 
home  of  beings  like  ourselves.  Again,  if  our  earth  be  not  the 
centre  of  the  universe,  but  one  of  a  number  of  planets,  and  a  small 
one  at  that,  then  the  other  planets  are  inhabited  hke  ours.  The 
arguments  thus  resolved  themselves  into  the  syllogism — aU  planets 
are  aHke,  the  earth  is  a  planet  and  is  inhabited,  ergo  all  planets  are 
inhabited.  The  peripatetic  philosopher,  Lagalla,  maintained  this 
thesis  in  a  pubhc  discourse  in  Rome  in  1612.  The  same  was 
gravely  adduced  by  Scheiner  in  one  of  the  numerous  digressions 
in  his  letters  on  Sun-spots,  and  he  insinuates  that  Galileo  must 
hold  the  beUef  as  a  necessary  consequence  of  his  observations. 

Yet  far  from  admitting  this  view,  Gahleo  took  pains  to  show 
its  impossibility.  In  his  third  letter  to  Welser  on  Sun-spots,  he 
points  out  that  for  fifteen  days  continuously  the  moon  is  exposed  to 
the  scorching  sun-rays,  and  for  another  fifteen  consecutive  days  is 

1  Nat.  Ed.,  vol.  iii,  Part  I.  ^  q£  ^^^  -^^^  ^^j  ^^^  ^  £40. 


THE  SCIENTIFIC  W0RK8  OF  GALILEO  247 

plunged  in  cold  and  darkness.  A  day  of  glare  and  heat  equal  to 
fifteen  of  ours,  and  a  night  of  cold  and  darkness  of  equal  length 
were,  he  pointed  out,  impossible  conditions  for  life  such  as  ours.^ 

17.  On  Finding  the  Longitude  at  Sea- 
Very  soon  after  he  had  discovered  the  satellites  of  Jupiter  in 
1610,  Galileo  began  a  work  the  difficulty  and  fatigue  of  which  he 
has  himself  indicated  by  comparing  it  with  the  labours  of  Atlas. 
It  was  a  series  of  observations  on  the  periods  of  the  satellites, 
'  with  a  view  to  drawing  up  tables  so  as  to  be  able  to  predict  all 
particulars  of  their  situations,  relations,  and  echpses,  and  thus  to 
have  the  means  of  determining  at  any  hour  of  the  night  the 
longitude  of  the  place  of  observation '.  Kepler  thought  tliis 
enterprise  so  difficult  as  to  be  wellnigh  impossible,  and  certainly 
Galileo  did  not  find  it  easy.  Notwithstanding  many  hundreds  of 
observations  in  the  next  twelve  months,  repeated  often  twice  and 
sometimes  three  times  in  a  night,  he  had  made  little  or  no  progress 
up  to  April,  1611.  It  was  not  until  another  year  and  more  had 
elapsed  that  he  was  able  to  announce  satisfactory  results-  in  his 
'  Discourse  on  Floating  Bodies  '.  To  show  their  close  approxima- 
tion, we  give  them  here  side  by  side  with  the  modern  figures. 

Periods  of  Revolution 

I  Galileo.  !  Modern. 

I 

Innermost  satellite .  .  I      1  day    18  hrs.  30  mins.  !  1  day    18  hrs.  29  mins. 

Second  „       .  .  !      3  days  13    „    20      „  3  days  13     „    18      ,, 

Third  „       .  .         7     „       4    „      0      „  |  7     „       4    „      0      „ 

Fourth  „       .  .       16     „     18     ,,      0      „  !  16     „     18    „      5      „ 

Our  moon  had  already,  been  suggested  for  the  same  purpose  : 
it  changes  its  position  amongst  the  stars  continuously,  and,  if  at 
specified  times  throughout  the  night  that  position  can  be  pre- 
dicted, the  mariner  is  able  to  determine  liis  longitude.  But,  at 
the  beginning  of  the  seventeenth  century,  tables  of  the  moon's 
positions  were  very  inaccurate  ;  and  even  its  proximity  to  the 
earth   was   a   disadvantage,   for   an   observer   at   sea   would   get 

1  Cf.  his  letter  to  Giacomo  Muti,  February  28,  1616  ;  Dialogue  of  1  632,  first 
Day. 

^  Cf.  Nat.  Ed.,  vol.  iii,  Part  II,  passim  ;  vol.  v,  pp.  415-25  ;  vol.  viii.  p.  451  ; 
vol.  xi,  p.  321  ;  vol.  xii,  pp.  256,  289,  311,  358,  392  ;  vol.  xiii,  pp.  17,  370  • 
vol.  xiv,  pp.  53,  91,  202,  349,  374. 

R  2 


24S  THK   SCIION'ril'IC    WOI^KS   OF  (^ALIl.KO 

a  (liflVrcnl  view  of  it  fioiii  one  on  land,  and  lliis  dijfcrcncc!  in  the 
moon's  position  ainon<;st  the  stars  \v<ndd  have  to  be  allowed  for. 
Tho  errors  due  to  these  defects  would,  it  was  tiion^^lit,  he  avoided 
if  Jupiter's  satellites  were  used  insteati  of  the  moon.  The  much 
greater  distanee,  the  frecpiency  of  tlieir  e(;lipHes  (more  than  1,000 
yearly),  and  (it  was  expected)  their  suddeiniess  se(Mned  to  |)romisc 
success  to  Galileo's  method.  But  in  practice  difficulties  cropped 
up.  First,  there  was  the  difficulty  of  observing  such  small  objects 
as  the  satellites  from  a  movijig  ship,  and  secondly,  there  was  the 
want,  common  to  both  methods,  of  accurate  time-keepers.  To 
obviate  the  first  he  contrived  what  he  called  the  Celatojie,  or 
T est  i era  : 

'  I  made',  he  saj's,  'for  the  use  of  our  navy  a  kind  of  cap, 
fitted  to  the  head  of  the  observer,  and  supporting  a  telescope  in 
such  a  way  that  it  always  points  in  the  same  direction  as  the 
free  eye,  so  that  an  object  viewed  bv^  the  latter  is  also  seen  by 
the  other  eye  through  the  telescope.  A  similar  apparatus  could 
be  made  and  fixed  on  the  shoulders  and  chest  of  the  observer, 
to  support  a  telescope  of  a  power  sufficient  to  show  the  satellites 
of  Jupiter,  and  adjustable  as  in  the  case  of  the  Celatone.  When, 
then,  the  free  eye  is  turned  towards  Jupiter,  the  other  eye  sees 
through  the  telescope  not  only  the  planet  but  its  satellites.'  ^ 

With  this  contrivance  and  a  chair  for  the  observer,  hung  like 
a  ship's  compass  on  a  binnacle,  he  hoped  to  overcome  the  first 
difificultv  of  unsteadiness  ;  while  to  remedy  the  second  he  had 
hopes  of  utilizing  his  early  observations  on  the  pendulum  and 
applying  it  as  an  exact  measurer  of  time. 

In  September,  1612,  Galileo  offered  his  method  to  the  Spanish 
Government  for  use  in  their  navy,  but  the  i^roposal  was  not  well 
received,  and  for  the  next  four  years  he  took  no  further  steps  in 
the  matter.  Now,  during  his  visit  to  Rome  in  1616,  he  reopened 
the  negotiations  through  Count  di  Lemos,  the  Spanish  Viceroj^  of 
Naples.  Di  Lemos  was  fully  alive  to  the  importance  of  the  pro- 
posal, and  promised  to  submit  it  to  his  Government.  This  was 
done,  after  much  unaccountable  delay,  in  March,  1617,  and,  in 
the  same  leisurely  way,  the  proposal  was  discussed  by  the  King 
in  Council.  To  the  various  objections  advanced  Galileo  repHed, 
and  even  offered  to  go  himself  to  Spain,  but  he  could  not,  with 
all  his  enthusiasm,  bring  the  Spanish  Court  to  a  decision.     His 

^  Letter  to  Lorenzo  Realio,  June  6,  1637.  From  this  it  is  clear  that  Galileo 
did  not  propose  a  binocular  telescope  as  has  sometimes  been  supposed. 


i 


THE  SCIENTIFIC   WORKS   OF  GALILEO  249 

disappointment  was  mitigated  by  liis  own  sovereign  taking  up 
the  method  for  use  in  the  Tuscan  navy.  Its  practical  apph cation, 
however,  proved  to  be  beset  witli  so  many  difficulties  tliat  it  soon 
fell  into  disuse.^ 

18.  On  Floating  Bodies  - 

During  the  summer  of  1611  the  subject  of  floating  bodies  had 
been  debated  at  one  of  the  scientific  parties  which  the  Grand 
Duke  liked  to  assemble  round  him.  The  general  opinion  was  that 
of  Aristotle,  that  the  sinking  or  floating  of  a  body  in  water 
depended  upon  its  shape.  Galileo  undertook  to  show  this  view 
to  be  untenable,^  and  he  embodied  his  arguments  in  a  famous 
treatise,  published  in  Florence  in  1612,  '  Discorso  intorno  alle  cose 
che  stanno  in  su  I'Acqua,  o  che  in  quella  si  muovono  '.  In  this 
work  he  restores  the  true  principles  of  hydrostatics  as  laid  down 
by  Archimedes,  alludes  to  the  so-called  hydrostatical  paradox, 
first  noticed  by  his  contemporary  Stevin  of  Bruges,  and  explains 
it  on  the  principle  of  virtual  velocities,  as  first  clearly  enun- 
ciated by  himself  in  his  treatise  on  the  mechanical  powers  in 
1594. 

In  the  course  of  the  discussion  it  was  asserted  that  condensation 
is  the  effect  of  cold,  and  ice  was  mentioned  as  an  example.  Galileo 
retorted  that  ice  is  rather  water  rarefied  than  water  condensed, 
the  proof  of  which  is  that  it  always  floats  upon  water.  His 
opponents  rejoined  that  this  was  due,  not  to  the  lightness  of  the 
ice,  but  to  its  incapacity,  owing  to  its  flat  shape,  to  overcome 
the  resistance  which  the  water  opposed  to  its  sinking.  Galileo 
denied  this,  and  asserted  that  ice  of  any  shape  would  float,  and 
that  if  a  flat  piece  were  forced  to  the  bottom  it  would,  when  left 
to  itself,  rise  again  to  the  surface. 

The  behaviour  of  ebony  was  then  instanced,  which  in  the  shape 

^  In  August,  1636,  Galileo  ofifered  his  method  to  the  States  General  of  Holland, 
but  here  again  its  practicability  was  questioned  and  for  the  same  reasons  as 
above.  The  negotiations  dragged  on  \\eaiily,  and  by  the  middle  of  1640  came  to 
an  infructuous  end,  except  for  a  collar  of  gold,  as  a  mark  of  the  Dutch  Govern- 
ment's esteem,  which  Galileo  refused,  or,  as  is  more  likely,  was  not  allowed  by 
the  Inquisition  to  accept. 

2  Cf.  Nat.  Ed.,  vol.  iv,  passim  ;   vol.  xi,  pp.  176,  304,  317. 

^  Cardinals  Gonzaga  and  Maffeo  Barberini  (afterwards  Pope  Urban  \'III) 
were  among  the  guests,  and  the  latter  took  Galileo's  side  in  the  discussion  against 
the  peripatetics  led  by  Gonzaga. 


250  THE  SCJEXTIKIC   WORKS   OF  GALILEO 

of  a  liall  sinks,  hut  as  a  thin  board  floats  when  gently  placed  on 
the  .surface.     To  this  he  re])lied  : 

*  The  diversity  of  figure  given  to  any  solid  cainiot  he  the  cause 
of  its  Moating  or  sinking  in  water,  though  the  breadth  of  the 
figure  may  indeed  retard  its  velocity  as  well  of  ascent  as  of  descent, 
and  more  and  more  in  proportion  to  the  breadth  and  thijiness. 
If  you  examine  carefully  your  thin  boards  of  wood  you  will  see 
that  they  have  part  of  their  thickness  under  water  ;  and,  more- 
over, you  will  see  that  shavings  of  ebony,  stone,  and  metal,  when 
tliey  float,  have  not  only  broken  the  contiiniity  of  the  water,  but 
arc  with  all  their  (hickne.s.s  under  the  surface,  and  this  more  and 
more  according  to  their  specific  gravity.' 

To  show  more  clearly  the  non-resistance  of  water  to  penetra- 
tion, he  directs  a  cone  to  be  made  of  wood  or  wax,  and  asserts 
that  when  it  floats,  either  with  its  base  or  its  apex  in  the  water, 
the  solid  content  of  the  part  immersed  will  be  the  same,  although 
the  apex  is  by  reason  of  its  shape  better  adapted  to  overcome 
the  resistance  of  the  water  to  division.  Shape,  then,  cannot  be  the 
cause  of  the  buoyancy.    He  goes  on  : 

'  Now%  let  us  return  to  the  thin  plate  of  gold  or  silver,  or  the 
thin  board  of  ebony,  and  lay  it  lightly  upon  the  water,  so  that 
it  may  staj^  there  without  sinking,  and  observe  the  effect.  It  will 
be  seen  that  the  board  or  plate  is  low^er  than  the  surface  of  the 
water,  which  rises  up  and  makes  a  kind  of  rampart  round  it.  But 
if  it  have  already  penetrated  the  water,  and  is  of  its  own  nature 
heavier  than  the  water,  why  does  it  not  continue  to  sink  ?  My 
answer  is,  because  in  sinking  till  its  surface  is  below  that  of  the 
water,  it  carries  with  it  the  air,  so  that  that  wliich  descends  is  not 
merely  the  board  of  ebony,  but  a  compound  of  ebony  and  air, 
from  which  results  a  body  no  longer  specifically  heavier  than  the 
water,  as  was  the  ebony  alone.  But,  gentlemen,  we  want  the  same 
matter  ;  you  are  to  alter  nothing  but  the  shape,  and  therefore 
have  the  goodness  to  remove  this  air.  This  may  be  done  by 
washing  the  upper  surface  of  the  board,  for  the  water,  having 
once  got  between  the  board  and  the  air,  will  run  together,  and 
the  ebony  will  sink  to  the  bottom.  To  demonstrate  how  truly 
the  air  does  support  these  solids,  I  have  found  that  when  one  of 
these  bodies  (which  float  when  placed  lightly  on  the  water)  is 
thoroughly  bathed  and  sunk  to  the  bottom,  by  carrying  down  to 
it  a  little  air,  without  otherwise  touching  it  in  the  least,  I  am 
able  to  raise  and  carry  it  back  to  the  top,  where  it  floats  as  before. 
To  effect  this  I  take  a  ball  of  wax,  and  with  a  little  lead  make 
it  just  heavy  enough  to  sink  slowly  to  the  bottom,  taking  care 
that  its  surface  is  quite  smooth  and  even.  This,  if  put  gently 
into  the  water,  submerges  almost  entirely,  there  remaining  outside 


THE  SCIENTIFIC  WORKS  OF  GALILEO  251 

only  a  very  little  of  the  top,  and,  so  long  as  it  is  thus  joined  to 
the  air,  the  ball  floats  ;  but  if  we  take  away  the  air,  by  wetting 
this  top,  the  ball  sinks  to  the  bottom.  .  .  .  There  is,  therefore, 
a  certain  affinity  between  air  and  other  bodies,  which  holds  them 
united,  so  that  they  separate  not  without  a  kind  of  violence,  just 
as  between  water  and  other  bodies,  for,  in  drawing  such  bodies 
wholly  out  of  the  water,  we  see  it  follow  them,  and  rise  sensibly 
above  its  level  before  it  quits  therti.' 

There  is  a  confusion  here  between  the  phenomena  of  hydro- 
static pressure  and  of  capillary  attraction  or  surface  tension ;  and 
Galileo  would,  perhaps,  have  carried  conviction  more  readily  had 
he  realized  himself  that  the  floating  plate  of  metal  indicated  a 
natural  property  of  liquids  which  deserved  special  investigation. 

This  book,  like  all  his  other  works,  encountered  violent  oppo- 
sition from  the  '  book  philosophers  ' ;  and  it  was  in  reference  to  this 
controversy  that  we  have  one  of  his  fine  obiter  dicta.  '  Ignorance  ', 
he  said,  '  had  been  the  best  teacher  he  ever  had,  since,  in  order 
to  be  able  to  demonstrate  to  his  opponents  the  truth  of  his  con- 
clusions, he  had  been  forced  to  prove  them  by  a  variety  of 
experiments,  though  to  satisfy  his  own  mind  alone  he  had  never 
felt  it  necessary  to  make  many.' 

19.  First  Encounter  with  the  Inquisition  ^ 

The  uncompromising  boldness  with  which  Galileo  published 
and  supported  his  opinions,  as  we  have  seen,  raised  crowds  of 
enemies  against  him.  The  Aristotelian  professors,  the  Jesuits,  the 
poHtical  churchmen,  and  those  timid  and  respectable  persons  who 
at  all  times  dread  innovation,  were  drawn  together  against  the 
man  who  threatened  them  with  the  penalties  of  too  much  know- 
ledge. No  longer  able  to  combat  his  observations  and  deductions 
by  asserting  that  the  former  were  due  to  faults  in  his  glasses  or 
to  apparatus  '  devilishly  designed  to  produce  them  ',  and  that  the 
latter  were  vainglorious  and  philosophically  absurd,  his  enemies 
now  took  their  stand  on  theology.  After  some  months  of  under- 
ground agitation,  Father  Caccini*,  of  the  Dominican  convent  of 
San  Marco,  was  the  first  to  declare  war  openly,  in  a  sermon  from 
the  pulpit  of  Santa  Maria  Novella  in  Florence.  Preaching  on  the 
fourth  Sunday  in  Advent  (December  21,  1614),  and  selecting  as 
his  text  Joshua  x.  12,  13,  and  Acts  i.  11,  he  opened  with  the  words : 

^  Cf.  Nat.  Ed.  vol.  v,  pp.  264,  281,  291,  309,  351  •  vol.  xii.  pp.  123,  183.  244, 
277  ;  vol.  xix,  pp.  272-421. 


252  TIIK   SCIKNTIKK!    WOKKS   OK   (;AIJLK() 

'  \'iii  (itililaoi,  ([liid  statis  aspiciciites  in  cii(.'luiii  ?  '  (jlalileo  explaiiu'cl 
and  defended  his  position  in  long  letters  to  Castelli,  to  Piero  Dini, 
and  to  the  Grand  Duchess  ( 'ristina( December,  1()14,  to  .liiiic,  HJIT)), 
which  to«^ether  constitute  a  powcjrful  A  jxthxjid.^ 

'Die  pith  of  his  argument  is  contained  in  the  saying  of  Cardinal 
Baronius,  which  he  quotes — '  The  Holy  Spirit  intended  to  teach 
us  in  {\\v  Bible  how  to  go  to  heaven,  jiot  how  tlic  heavens  go'. 
One  or  two  passages  fiom  his  letter  to  the  Crand  Duchess  may 
be  quoted  : 

'  Methinks  that  in  the  discussion  of  natural  jnoblems  we  ought 
not  to  begiji  with  tlie  authority  of  passages  from  Scripture,  but 
with  sensible  experiments  and  necessary  demojistrations.  .  .  . 
Nature  being  inexorable,  acting  only  through  immutable  laws 
which  she  never  transgresses,  and  caring  nothing  whether  her 
reasons  and  methods  of  operating  be  or  be  not  understandable 
by  men,  1  hold  that  our  conception  of  her  works,  which  either 
sensible  experience  sets  before  our  eyes,  or  necessary  demonstra- 
tions prove,  ought  not  to  be  called  in  question — much  less  con- 
demned upon  the  testimony  of  Scriptural  texts  which  may  conceal 
under  their  words  senses  or  meanings  seemingly  opposite.  ...  To 
command  professors  of  astronomy  that  they  see  to  confuting  their 
own  observations  and  demonstrations  is  to  ask  the  impossible.  .  .  . 
As  to  opinions  which  are  not  directly  articles  of  faith,  certainly, 
no  man  doubts  that  his  Holiness  hath  always  an  absolute  power 
of  admitting  or  condemning  them  ;  but  it  is  not  in  the  power  of 
any  creature  to  make  them  to  be  true  or  false  otherwise  than  as 
they  are.' 

All  through  the  year  1615  the  agitation  went  on  with  unabated 
violence,  denunciations  were  sent  to  the  Holy  Office,  and  the 
Inquisition  began  to  make  secret  inquiries.  At  length  the  situa- 
tion became  so  threatening,  not  only  for  our  philosopher  himself, 
but  for  science  in  general  and  the  Copernican  theory  in  particular, 
that  Galileo,  with  the  advice  of  friends,  decided  to  take  himself 
to  Rome.  Accordingly,  on  December  3,  1615,  he  set  out,  pro- 
vided with  cordial  letters  from  the  Grand  Duke  to  his  Ambas- 
sador Guicciardini,  to  Cardinals  del  Monte  and  Orsini,  and  others. 
After  many  weeks  of  alternating  hopes  and  fears,  the  matter  came 
officially  before  the  Inquisition,  with  the  result  that  on  February 
26,  1616,  Cardinal  Bellarmine,  who  had  sat  on  the  commis- 
sion that  investigated  his  discoveries  on  his  former  visit  to 
Rome,  was  directed  '  to  summon  before  him  the  said  Galileo, 
and  admonish  him  to  abandon  the  said  opinions,  and,  in  case  of 
^  Cf.  his  letter  to  Francesco  Ingoli,  Nat.  Ed.,  vol.  vi,  pp.  504-61. 


THE  SCIENTIFIC  WORKS   OF  GALILEO  258 

refusal,  the  Commissar}^  is  to  iiitimate  to  liiiii,  before  a  notary 
and  witnesses,  a  eoniniand  to  abstain  altogetlier  from  teaching  or 
defending  the  said  opinions,  and  even  from  discussing  them.  If 
he  do  not  acquiesce  therein,  he  is  to  be  imprisoned  '. 

Here  the  process  ended  so  far  as  Gahleo  was  concerned,  but 
on  March  5  a  decree  was  issued  prohibiting,  and  suspending 
certain  writings.  Amongst  them  the  book  of  Copernicus  {Revolu- 
tions of  the  Celestial  Orbs,  first  pubhshed  1543)  was  ordered  to 
'  be  suspended  until  corrected  '.  Gahleo  appears  to  have  taken 
the  admonition  with  a  very  bad  grace,  if  we  are  to  believe  Guic- 
ciardini,  who  was  no  friend  of  his.  Writing  to  the  Grand  Duke 
on  May  13,  1616,  he  says  : 

'  Galileo  seems  disposed  to  emulate  the  monks  in  obstinacy.  .  .  . 
It  may  be  heard  at  any  moment  that  he  has  stumbled  into  some 
new  abyss  or  other.  However,  the  heat  will  jjrobabl}^  drive  him 
from  Rome  before  long,  and  that  will  be  the  best  thing  that  can 
happen  to  him.'  ^ 

20.  The  Tides- 

Yet  amidst  all  these  cares  and  worries  Galileo's  teeming  mind 
was  busy  with  many  scientific  problems.  He  had  not  been  many 
days  in  Rome  when  a  suggestion  from  Cardinal  Orsini  was  enough 
to  start  him  on  a  treatise  on  the  Flux  and  Reflux  of  the  Sea. 
This  problem  had  from  the  earliest  ages  deserved  its  name — '  The 
grave  of  human  curiosity  '.  Some  supposed  the  rise  of  the  waters 
to  be  due  to  the  influx  of  rivers  ;  others  supposed  the  existence 
of  subterraneous  fires  which  periodically  made  the  sea  to  boil  up  ; 
while  others  again  attributed  this  boiling  effect  to  changes  of 
temperature  in  the  sun  and  moon,  or  to  variations  in  the  amount 
of  their  hght. 

The  ancient  philosophers  had  vague  ideas  that  the  moon's 
attraction  was  the  cause.  '  The  flow ',  says  Pliny,  '  takes  place 
every  day  at  a  different  hour,  according  to  the  rising  of  the  moon, 
which,  with  greedy  draught,  drags  the  seas  along  wuth  it.'  In 
modern  times,  Gilbert  of  Colchester  had  speculated  on  this  con- 
nexion. '  There  are ',  he  says,  '  two  primary  causes  of  the  motion 
of  the  seas — the  moon  and  the  diurnal  revolution  of  the  earth. 

^  Cf.  letter  from  Mgr.  Antonio  Querengo  to  Cardinal  d'Este,  January  20, 
1616  ;  and,  on  the  other  side,  Cardinal  del  Monte's  letter  to  the  Grand  Duke, 
June  4,  1616. 

2  Cf.  Nat.  Ed.,  vol.  v,  pp.  373-95. 


254  THIO   SCIKXTII  M'    WOIIKS   OK   CALII.KO 

Tlif  moon  (Iocs  not  act  on  tlic  .seas  by  its  licat  rays,  or  by  its 
lij^lht.  How,  then  V  (Vrtainly  by  tljo  cominoii  or  iiuitual  effort  of 
the  bodies,  or,  to  explain  it  by  Honiel  liin^  similar,  by  tlieir  magnetic 
attraction.'  'I'lie  .lesnits  of  the  celebrated  college  of  Coimbra,  as 
well  as  Marc  Antonio  de  Dominis,  onee  Catholie  Archbisho]>  of 
Spahitro,  later  Protestant  Canon  of  Windsor,  and  finally  himself 
a  martyr  of  the  Inquisition,  and  Ke))ler,  tlie  law-giver  of  the 
planets,  all  held  mueh  the  same  views.  Kepler's  words  are  worth 
quoting,  as  they  embody  his  ideas  of  that  universally  mutual 
gravitation,  whicii  Borelli,  VVallis,  and  Hooke  after  him  saw  more 
clearly,  and  wliieh  it  was  the  glory  of  Newton  to  establish  : 

'  Gravity  is  a  mutual  affection  between  cognate  bodies  towards 
union,  similar  in  kind  to  the  magnetic  virtue,  so  that  the  earth 
attrjicts  a  stone  more  than  the  stone  attracts  the  earth.  Assuming 
the  earth  to  be  the  centre  of  the  world,  then,  wherever  it  may  be, 
or  wheresoever  it  may  be  carried  by  its  animal  faculty,  heavy 
bodies  will  always  incline  towards  its  centre.  If  two  stones  be 
placed  in  any  part  of  the  universe  near  each  other,  and  beyond  the 
influence  of  a  third  cognate  body,  they,  like  two  magnetic  needles, 
will  come  together  at  an  intermediate  point,  each  approaching  the 
other  by  a  space  proportionate  to  its  mass.  If  the  moon  and 
the  earth  ^^'ere  not  retained  in  their  orbits  by  their  animal  force, 
or  some  other  equivalent,  the  earth  would  mount  towards  the 
moon  by  one  fifty-fourth  part  of  the  distance  between  them,  and 
the  moon  would  fall  towards  the  earth  by  the  other  fifty-three 
parts,  i.e.  in  the  inverse  ratio  of  their  masses,  and  assuming  their 
substances  to  be  of  the  same  density.  If  the  earth  should  cease 
to  attract  its  waters  to  itself,  all  the  waters  of  the  sea  would  be 
raised  and  flow  towards  the  moon.  This  attractive  \irtue  of  the 
moon  extends  as  far  as  the  earth,  and  entices  its  waters,  but,  as 
she  flies  rapidly  across  the  zenith,  and  the  waters  cannot  follow 
so  quickly,  a  flow  of  the  ocean  is  occasioned  in  the  torrid  zone 
and  towards  the  west.'  ^ 

Gahleo's  theory  is  that  the  tides  are  the  visible  effects  of  the 
terrestrial  double  movement,  since  they  are  the  combined  result 
of  (1)  the  earth's  dailj'  rotation  on  its  axis,  and  (2)  the  inequahty 
of  the  absolute  velocities  of  the  various  parts  of  the  earth's  surface 
in  her  revolution  round  the  sun.  In  the  whole  range  of  the 
sciences  over  Avhich  Gahleo  left  indelible  marks  of  his  genius,  he 

^  Astronomia  Xova,  Prague,  1609.  Ten  years  later  Kepler  abandoned  these 
correct  ideas,  and  depicted  the  earth  in  his  Harmonice  Mundi  as  a  living  monster 
whose  whale-like  mode  of  breathing  occasioned  the  rise  and  fall  of  the  oceans  in 
recurring  periods  of  sleeping  and  waking  dependent  on  solar  time. 


I 


THE  SCIENTIFIC   WORKS   OF  GALILEO  255 

made  very  few  fundamental  errors,  and  this  is  perhaps  his  most 
serious  one.^ 

2L  On  Comets  and  '  //  Saggiatore  '  - 

In  August,  1618,  three  comets  appeared,  and  the  very  brilliant 
one  in  the  constellation  of  the  Scorpion — one  of  the  most  splendid 
of  modern  times — especially  attracted  the  attention  of  astronomers. 
Although  this  comet  was  visible  until  January,  1619,  Galileo  had 
little  opportunity  of  observing  it,  as  he  was  confined  to  bed  nearly 
the  whole  time.  However,  on  a  small  basis  of  observation  he 
reflected  much  and  imparted  his  views  to  his  friends,  amongst 
others  to  Mario  Guiducci,  a  Florentine  disciple.  In  May  of  the 
same  year,  1619,  Guiducci,  in  a  Presidential  address  to  the  Acca- 
demia  Florentina,  gave  the  views  of  the  Master — '  not  as  demon- 
strative truth,  but  as  plausible  conjectures  in  a  matter  so  abstruse  '. 

This  address  was  published  immediately  under  the  title  Discorso 
delle  Comete  (Florence,  1619),  and  from  it  we  learn  that  Galileo 
did  not  regard  comets  as  heavenly  bodies  analogous  to  the  planets, 
but  as  atmospheric  phenomena — columns  of  vapour  which,  rising 
from  the  earth  to  great  heights,  far  beyond  the  moon  {spazi 
celesti),  became  there  temporarily  visible  by  reflection  of  the  sun's 
light.  In  fact,  he  classed  them  in  the  same  category  as  rainbows 
and  mock  suns,  thus  for  once  agreeing  with  Aristotle,  and  opposing 
himself  to  the  more  correct  views  of  his  contemporaries,  Tycho 
Brahe  and  Kepler.^  Referring  to  some  proposed  observations  for 
parallax  he  pointed  out  the  difference  in  this  respect  between 
a  fixed  object,  the  distance  of  which  may  be  calculated  by  two 
angular  observations  at  a  known  distance  apart,  and  atmospheric 
appearances  like  rainbows,  which  are  simultaneously  formed  in 
different  drops  of  water  for  each  spectator,  so  that  two  observers 
in  different  places  are,  in  fact,  vie^ving  different  objects.    He  then 

^  Between  1630  and  1637  Galileo  would  seem  to  have  changed  his  view  and 
suggested  that  the  moon's  librations  may  be  the  cause  of  the  tides — '  which  by 
the  common  consent  of  all  philosophers  are  ruled  by  the  moon  '.  See  his  letters 
to  Fulgenzio  Micanzio,  7th  November,  1637,  and  to  Alfonzo  Antonini,  20th  Feb- 
ruary, 1638. 

2  Cf.  Nat.  Ed.,  vol.  vi,  passim  ;  vol.  xi,  p.  41  ;  vol.  xii,  pp.  466,  494  ;  vol. 
xiii,  pp.  43,  46,  80,  90,  98,  106,  116,  142  ;  vol.  xviii,  p.  423. 

^  Brahe  thought  that  comets  were  the  result  of  sudden  condensations  of  the 
ether  of  space,  while  Kepler  accounted  them  to  be  exhalations  of  the  planets. 
Santucci  held  that  they  were  produced  in  the  heavens  by  the  sun.  See  his 
Trattato  nvovo  delle  Comete,  Fiorenza,  1611.  In  later  years,  Galileo  changed  his 
opinion  as  to  their  '  probably  terrestrial  "  origin. 


2r>6  THK   SCIKXTiriC    WOIIKS   OK   ('..\\A\A<:() 

warns  aslroiiointTs  not  to  ('nji;a;^c  in  a  disciisHion  on  tlic  distance 
of  coriH'ts  licforo  they  aHsiiro  tlicmselves  to  wliicli  of  tlicHc  two 
clasHcs  of  pliciunncna  they  are  to  he  referred.  The  remark  is  in 
itself  perfectly  just,  although  the  opinion  nliich  occasioned  it  is 
now  known  to  be  erroneous  ;  but  it  is  questionable  whether  the 
few  observations  which  up  to  that  time  had  been  made  upon 
comets  were  sufficient  to  justify  the  censures  which  have  been 
ciust  on  (Galileo  on  account  of  it. 

Ill  the  course  of  (;!uiducci's  essay,  some  opinions  of  the  .Jesuit 
Father,  Orazio  Grassi,  were  so  indiscreetly  luindled  as  to  raise  the 
ire  of  the  Jesuits'  (*ollege  at  Rome.'  (Jrassi,  under  the  pseudonym 
of  Lotario  Sarsi,  })ublished  an  onslaught  on  Galileo's  cometary 
theory  in  a  book  called  The  A.slronoinical  (uid  P/illosojjhical  Balance 
{H)\9) — a  violent  i)amphlet  full  of  abuse  of  Galileo  and  his  school. 
Friends,  like  Prince  Cesi  and  Mgri.  Ciampoli  and  Gesarini,  now 
advised  that  the  master  himself  should  take  up  the  i^ght  ;  but 
ill  health  and  the  troubled  state  of  the  religious  and  ])olitical 
horizons  ])rcvented  the  appearance  of  his  reply  for  four  years. 
At  length,  on  October  19,  1622,  he  sent  the  manuscript  of  11 
Saggiatore  (The  Assay er)  to  Mgr.  Cesarini  in  Rome,  and  for  five 
months  it  passed  from  hand  to  hand  among  the  members  of  the 
Accademia  dei  Lincei,  who  examined  it  carefully  and  (with  the 
author's  consent)  altered  some  passages  which  might  possibly  have 
given  a  handle  to  his  enemies.  The  Papal  Imprimatur  was 
granted  on  February  2,  1623,  and  the  book  appeared  at  the  end 
of  October  with  a  dedication  to  Pope  Urban  VIII,  and  under  the 
auspices  of  the  Accademia  dei  Lincei.  This  celebrated  work  is 
a  masterpiece  of  dialectics,  for  the  author  not  only  dexterously 
avoids  the  snares  laid  for  him  by  Father  Grassi  and  his  abettors, 
but  brings  defeat  and  ridicule  upon  them  at  every  turn.  He 
takes,  in  order,  the  mistakes  of  his  adversary,  his  false  citations 
and  false  deductions,  his  errors  of  logic,  of  geometry,  of  physics,  of 
astronomy,  and  exposes  them  all ;  and  this  is  done  so  courteously 
and  in  such  sparkling  style  that  II  Saggiatore  deserves  its  reputa- 
tion as  a  model  of  dialectic  skill,  and  an  ornament  of  classical 
Italian  literature. 

The  book  (Fig.  10)  was  a  great  success,  but  it  intensified  the 

^  Soon  after  the  apjjearance  of  the  comets,  a  discussion  upon  them  took 
place  in  the  CoUegio  Romano.  It  was  published  early  in  1619  under  the  title 
De  Tribus  Cometis  anni  1618  .•  Disputatio  Astronomica,  &c.  It  is  interesting  to 
note  that  Mazarin,  then  a  boy  of  sixteen,  took  part  in  this  discussion. 


THE  SCIENTIFIC   WORKS   OF  GALILEO  257 

bitterness  of  the  Jesuitical  party,  and  the  General  of  the  Order 
forbade  the  members  to  speak  of  it,  even  among  themselves.  It 
is  important  to  note  that  the  Pope  was  delighted  with  it,  and 
had  it  read  aloud  to  him  at  table.  Early  in  1625  the  book  was 
denounced  anonymously  to  the  Inquisition  as  a  veiled  defence  of 
the  Copernican  doctrines,  and  a  movement  was  begun  to  have 
it  prohibited,  or,  at  least,  '  corrected  '.  This  attempt,  however, 
failed,  and  brought  only  further  discredit  upon  the  agitators. 

I^".    The  Trial  and  Abjuration 

1.  Galileo's  Plea  for  Coi)ernicanis7n 
On  the  election  of  Cardinal  Maffeo  Barberini  to  the  Papacy 
as  Urban  VIII,  August  8,  1623,  Galileo  conceived  the  idea  of 
going  to  Rome  to  offer  his  congratulations  in  person,  and  to  use 
his  influence  with  the  new  Pope  to  obtain,  at  least,  toleration  for 
the  Copernican  doctrines,  now  no  longer  subject  to  the  weight}^ 
opposition  of  Cardinal  Bellarmine,  who  died  two  years  before. 
Remembering  the  warmth  of  Barberini's  regards  for  him  while 
Cardinal,  Galileo  had  much  to  hope  from  a  Pontiff  so  enlightened. 
He  was  encouraged,  moreover,  by  hopeful  reports  from  friends  in 
Rome.  Prince  Cesi,  writing  October  21,  1623,  was  able  to  tell  him  : 
'  Under  the  auspices  of  this  most  excellent,  learned,  and  benignant 
pontiff  science  must  flourish.  .  .  .  Your  arrival  will  be  welcome 
to  his  Holiness.  He  asked  me  if  you  were  coming  and  when,  and, 
in  short,  seems  to  love  and  esteem  you  more  than  ever.'  Rinuccini, 
Cesarini,  Ciampoli,  and  others  wrote  in  the  same  strain.  Ciampoli, 
the  Pope's  private  secretary,  wrote  on  March  16,  1624  :  '  It  is 
certain  that  the  longer  your  coming  is  deferred  the  more  it  is 
desired  by  all  those  gentlemen  who  esteem  you,  and  keep  you 
green  in  their  memory.  You  will  find  in  the  Holy  Father  no 
ordinary  affection  towards  your  person.'  Ill-health,  however,  and 
then  the  bad  weather  and  worse  roads,  intervened,  but,  at 
length,  Galileo  set  out  for  the  Eternal  City  on  xA.pril  1,  1624. 

All  Rome  was  aware  of  the  favour  in  which  the  Pope  held 
Galileo,  and  his  letters  express  great  satisfaction  with  his  reception, 
but  as  regarded  the  object  which  was  nearest  his  heart,  he  made 
no  progress.  Within  six  weeks  he  had  had  six  long  interviews 
with  Urban  VIII,  who  always  received  him  most  affably,  and 
allowed  him  to  bring  forward  all  his  arguments  in  support  of  the 
Copernican  theory  ;    but  all  to  no  purpose  ;    for  while  the  Pope 


268  THE  S(4ENTIFIC   WORKS   OF  GALILKO 

listened  to  hiw  arguments,  he  would  not  grant  his  entreaties  for 
even  a  passive  toleration  of  the  new  doctrines. 

Finding  that  Iiis  efforts  to  g(^t  th(^  decree  of  March  5, 
1616,  revoked  were  of  no  avail,  (jiahleo  resolved  with  a  heavy 
heart  to  return  home,  though  the  Pope  had  loaded  him  with 
favours  whicli  must  liave  seemed  like  mockeries.  His  Holiness 
promised  him  a  pension  for  his  son,  and  sent  a  ])ictur(i  for  himself  ; 
then  two  medals— one  of  gold  and  one  of  silver,  and  quite  a  number 
of  Agnus  Dei  !  Not  content  with  these  marks  of  favour,  he 
addressed  an  official  letter  to  the  Grand  Duke,  on  .June  8,  in 
which,  to  the  no  small  chagrin  of  Galileo's  enemies,  his  Holiness 
not  only  did  full  justice  to  our  philosopher's  services  to  science, 
'  the  fame  of  which  will  shine  on  earth  so  long  as  Jupiter  and  his 
satellites  shine  in  heaven  ',  but  laid  special  stress  on  his  religious 
sentiments.  Yet  Galileo  departed  with  the  object  of  his  visit 
unsatisfied. 

2.  Dialogue  on  the  Two  Chief  Systems  of  the   World, 
the  Ptolemaic,  and  the  Copenilcan  ^ 

Nevertheless,  from  various  indications  in  the  ecclesiastical 
world  in  the  next  two  years,  1624-6,  Galileo  was  led  to  think 
that  the  advocates  of  Copernicanism  had  now  little  to  fear,  pro- 
vided that  the  defence  was  so  circumspectly  handled  as  not  to 
outrage  the  Inquisition's  decree  of  March  5,  1616,  which  con- 
demned the  doctrine  not  as  '  heretical ',  but  only  as  '  rash  \'^ 
He  resolved  to  push  on  to  completion  a  work  he  had  contemplated 
as  far  back  as  1610,  This  was  to  be  entitled  A  Dialogue  on  the 
Flux  and  Reflux  of  the  Tides.  From  1626  to  1630  he  was  almost 
entirely  engaged  on  this  W'Ork,  but  was  interrupted  by  frequently 
recurring  illnesses  and  family  troubles.^ 

At  length,  by  the  beginning  of  1630,  he  had  practically  com- 
pleted this  Dialogue,  and  in  announcing  the  fact  to  his  friend 

1  Cf.  Xat.  Ed.,  vol.  vii ;  vol.  xiii,  pp.  104,  236,  260-4,  365  ;  vol.  xiv,  pp.  49, 
64-70,  79,  97,  120,  150-67,  278-85,  331 ;  vol.  xix,  pp.  327-30. 

2  Indeed  it  was  known  that  Urban  VIII,  as  Cardinal,  did  not  approve  of  that 
decree.  Earl}'  in  1630,  when  discussing  it  with  Campanella  he  said  :  It  was  never 
our  intention  and,  if  it  depended  upon  us,  that  decree  would  not  have  been 
issued  '  (Nat.  Ed.,  vol.  xiv,  p.  88). 

♦  ^  About  this  period  he  was  often  consulted,  ^^ith  others,  on  hydraulic  ques- 
tions connected  -with  the  flooding  of  Tuscan  rivers  (Nat.  Ed.,  vol.  vi,  p.  613). 
Cf .  Cambiagi,  Raccolta  d'Autori  che  trattano  del  moto  dell'  Acqua,  Firenze,  1765-74 ; 
Napier,  Florentine  History,  London,  1847. 


THE  SriEXTIFKJ  WORKS   OF  GALILEO  259 

Prince  Cesi,  he  expressed  his  intention  of  going  himself  to  see  to 
the  printing  at  Rome,  where  the  state  of  affairs  seemed  still 
favourable  for  this  enterprise.  Galileo's  disciple,  Castelli,  had 
been  called  from  Pisa  in  March,  1626,  to  be  mathematician  to  the 
Pope,  and  enjoyed  great  consideration  with  all  the  members  of 
the  Barberini  family.  This  life-long  friend,  like  Cesi,  approved 
the  design,  and  informed  our  philosopher  (February  9)  that  Father 
Niccolo  Riccardi,  another  old  pupil  and  now  chief  censor  of  the 
press,  had  promised  his  assistance.  Filled  with  hope  and  with  his 
manuscript  complete,  Galileo  at  length  set  out  on  May  1  in 
a  Court  litter,  and  travelling  fast  arrived  in  Rome  on  the  evening 
of  the  3rd.  He  had  a  long  audience  of  the  Pope,  and  wrote  on 
May  18  to  Florence  in  high  spirits:  'His  Holiness  has  begun 
to  treat  my  affairs  in  a  way  that  permits  me  to  hope  for  a  favour- 
able result '.  But  Galileo  was  far  too  sanguine,  for  toleration,  to 
say  nothing  of  the  recognition,  of  the  Copernican  theory  was  as 
far  off  as  ever.  Urban  VIII  would  not  object  to  the  publication, 
but  certain  conditions  must  be  fulfilled.  The  title  of  the  book, 
Dialogue  on  the  Flux  and  Reflux  of  the  Tides,  was  misleading  and 
must  be  altered.  The  subject,  being  a  discussion  of  the  relative 
merits  of  the  Copernican  and  Ptolemaic  systems,  should  be  indi- 
cated in  the  title.  The  subject,  moreover,  would  have  to  be 
treated  from  a  purely  hypothetical  standpoint,  and  this  fact  must 
be  clearly  set  forth  in  a  preface.  Then,  the  book  must  conclude 
with  an  argument  which  the  Pope  communicated  to  Galileo  in 
1624,  and  which  his  Holiness  considered  unanswerable.  That 
argument  was  as  follows  :  '  God  is  all-powerful ;  all  things  are 
therefore  possible  to  Him  ;  ergo  the  tides  cannot  be  adduced  as 
a  necessary  proof  of  the  double  motion  of  the  earth  without 
limiting  God's  omnipotence.'  Rather  than  forgo  the  publication 
of  a  work  towards  which  he  had  laboured  and  thought  for  over 
thirty  years,  Galileo  consented  to  these  conditions. 

Meanwhile  the  manuscript  had  been  submitted  to  Father 
Riccardi,  who,  after  certain  revisions  and  alterations,  granted 
permission  for  the  printing  in  Rome.  Thus,  by  the  end  of  June, 
1630,  Galileo  was  back  in  Florence  with  his  manuscript  revised 
and  corrected,  and  with  the  ecclesiastical  Imprimatur  for  its 
publication  in  Rome,  on  the  understanding  that  a  preface  and 
conclusion  would  be  added  in  accordance  with  the  Papal  wish. 
Publication  seemed  imminent,  yet  for  another  twenty  months  our 
author  was  tormented  with  obstacles  and  delays  on  the  part  of 


2<)0  'INK   SCIKXTIKIC    WOIIKS    OT   (iALILKO 

the  censors,  now  in  Home,  now  in  Florence.  It  wonld  he  little 
proHtahle  to  set  out  in  (l<'tail  these  (jiiihhHii^  complications;  hut 
the  work  was  at  last  issued  from  the  Florentine  presK  in  Fehruary, 
l().*i2.  It  was  in  Italian,  was  dedicated  to  Ferdinando  II  of 
Tuscany,  and  hore  the  title,  '  Dialogue  of  (^alilco  (ialilei,  Jiyncean, 
Mathematician  Extraordinary  of  the  University  of  Pisa,  Philo- 
sopher and  First  Mathematician  of  the  Most  Serene  Grand  Duke 
of  Tuscany;  where  in  nieetin<is  of  four  Days  are  discussed  the 
Two  Chief  Systems  of  the  World,  indeterminately  proposing  the 
Philosophical  and  Natural  arguments,  as  well  on  one  side  as  on 
the  other  '. 

The  dialogue  is  carried  on  hy  three  interlocutors,  of  whom  two 
adduce  the  scientific  reasons  for  the  douhle  motion  of  the  earth, 
while  the  third  tries  to  defend  the  opinions  of  the  Ptolemaic  and 
Aristotelian  schools.  Galileo  gave  to  the  defenders  of  the  Copernican 
doctrine  the  names  of  two  of  his  warmest  friends,  both  long  dead — 
Filip]:>o  Salviati  of  Florence  (d.  1614),  and  Giovanni  Francesco 
Sagredo  of  Venice  (d.  1620).  Salviati  is  the  special  advocate  of 
the  Copernican  doctrine  ;  Sagredo  is  witty,  impartial,  and  open 
to  conviction.  To  him  are  allotted  such  objections  as  have  real 
force,  as  well  as  lively  illustrations  and  digressions,  which  would 
be  inconsistent  with  the  gravity  of  Salviati's  character.  Simplicio, 
a  name  borrowed  from  the  noted  Cilician  commentator  of  Aristotle 
who  wTote  in  the  sixth  century,  is  a  confirmed  Ptolemaist  and 
Aristotehan,  and  produces,  as  occasion  requires,  all  the  arguments 
of  the  peripatetic  school ;  and  as  these  fail  to  convince  he  has 
recourse  to  all  the  arts  of  sophistry. 

The  condition  that  the  Copernican  doctrine  is  to  be  treated 
as  an  hypothesis  is  ostensibly  complied  with.  If  Salviati  or 
Sagredo  show  the  untenableness  of  some  Ptolemaic  axiom,  or  add 
a  stone  to  the  Copernican  structure,  a  remark  is  interpolated  by 
one  or  other  to  weaken  the  effect.  When  we  remember  its  history 
we  cannot  be  surprised  that  the  preface  or  introduction  has  no 
logical  agreement  with  the  contents  of  the  Dialogue.  The  con- 
clusion agrees  no  better  than  the  preface  with  the  body  of  the 
work.  At  the  end  of  the  fourth  Day,  which  is  almost  wholly 
taken  up  with  the  tides,  comes  naturally  the  Pope's  '  unanswer- 
able '  argument  of  1624.  Salviati  treats  it  accordingly  :  '  It  is  '. 
he  says,  '  an  admirable  and  truly  angelic  argument,  and  perfectly 
in  accord  with  that  which,  coming  from  God  Himself,  permits  us 
to  discuss  the  constitution  of  the  world — doubtless  with  the  view 


THE  SCIENTIFIC  WORKS  OF  GALILEO  201 

of  preventing  by  exercise  the  diminution  and  enfeeblement  of  our 
intellectual  faculties,  while  withholding  from  us  the  power  of  fully 
comprehending  the  works  of  His  hands.' 

The  contents  of  the  Dialogue  can  be  given  only  in  outline. 
Salviati  opens  by  defining  its  object,  which  is  to  examine  all  the 
physical  arguments  evoked  for  and  against  their  opinions  by  the 
defenders  of  Aristotle  and  Ptolemy  on  the  one  hand,  and  of 
Copernicus  on  the  other.  In  a  few  words,  the  Aristotelian  doctrines 
amounted  to  a  statement  that,  whereas  things  earthly  are  imperfect 
and  full  of  change,  things  heavenly  are  eternal,  unchangeable,  and 
perfect.  Salviati  proves  that  this  statement,  in  the  spirit  in  whicli 
it  was  usual  to  accept  it,  is  untenable.  The  telescope  shows 
imperfections  on  the  sun's  surface,  while  the  recently  observed 
new  stars  (of  1572  and  1604)  are  instances  of  change  in  the  heavens. 
He  thus  prepares  the  way  for  a  still  wider  departure  from  Aristo- 
telian theory  ;  he  insists  that  the  time  has  come  to  consider  the 
nature  of  the  world  de  novo,  suggesting  that  Aristotle,  had  he  the 
opportunities  which  the  telescope  afforded,  would  himself  have 
realized  the  inadequacy  of  his  own  teaching. 

Salviati  proceeds  to  point  out  certain  resemblances  between 
the  earth  and  moon  and  the  more  distant  heavenly  bodies.  It 
was  admitted  that  the  moon  shines  only  in  virtue  of  the  sunlight 
falling  on  her.  The  idea  that  the  earth  might  similarly  appear 
luminous  to  an  inhabitant  of  the  moon  is  less  familiar  and  less 
readily  accepted.  And  yet  the  visibility  of  the  moon  during 
a  total  eclipse  of  the  sun,  and  the  appearance  '  of  the  old  moon 
in  the  arms  of  the  new  '  (as  we  now  speak  of  it),  are  due  most 
probably  to  reflected  earth-light.  The  phenomena  of  Venus's 
phases  are  shown  to  be  similar  to  those  of  the  moon,  and  may 
be  explained  as  due  to  the  same  cause.  Venus,  then,  like  the 
moon,  owes  her  brilliance  to  the  sun's  light  falling  on  her.  The 
same  probably  applies  to  Mercury  and  Mars.  The  obvious  inference 
seems  to  be  that  all  these  heavenly  bodies  are  not  so  unlike  the 
earth  as  men  had  thought.  Points  of  resemblance  there  cer- 
tainly are,  and  there  may  be  many  more  which  the  distance 
of  the  planets  alone  prevents  us  from  discovering.  Salviati  then 
refers  to  the  spherical  form  common  to  earth,  sun,  moon,  and 
planets,  and  suggests  the  existence  of  a  common  cause  for  that 
shape. 

Here  follow  some  remarks  which  show  the  idea  of  universal 

2391  a 


262  THK  SriF.NTIFIC   WORKS   OF   (lAIJLKO 

j^raviiat  ioM  hovering  in  Oalih'os  mind.  He  ixTccivcd  the  analogy 
bctwecMi  i\w  power  whicli  liolds  th(^  moon  in  the  neigh bourliood 
of  the  earth  and  compels  .Jupiter's  satellites  to  circulate  round 
their  primary,  and  that  attractive  power  wliich  tlu^  mirth  exercises 
on  bodies  at  its  surface  ;  but  he  failed  to  conceive  the  combination 
of  central  force  with  initial  velocity,  and  was  disposed  to  connect 
the  revolutions  of  the  planets  with  the  axial  rotation  of  the  sun — 
a  notion  which  tended  more  towards  Descartes'  theory  of  vortices 
than  towards  Newton's  theory  of  gravitation. 

Having  laid  stress  on  the  resemblance  of  earth  and  i)lanets, 
Salviati  proposes  for  them  all  a  similar  motion  round  the  sun — 
one  of  the  two  main  points  of  the  Copernican  theory.  He  shows 
how  the  apparent  paths  of  all  the  planets  can  be  thus  explained, 
and  in  a  far  simpler  way  than  by  the  Ptolemaic  formula.  On 
the  Copernican  hypothesis  all  motions  of  revolution  and  rotation 
take  place  in  the  same  direction  from  west  to  east,  whereas  the 
Ptolemaic  system  requires  some  to  be  in  one  direction  and  some 
in  another.  A  glance  through  a  telescope  turned  towards  Jupiter 
shows  a  family  of  small  bodies  circling  round  a  great  planet ; 
here  one  could  see  on  a  small  scale  the  very  thing  that  Copernicus 
had  described  as  going  on  in  the  case  of  planets  and  sun. 

On  the  second  Day  the  discussion  passes  to  the  other  chief 
point  in  the  Copernican  hypothesis — that  the  apparent  daily 
motion  of  the  stars  is  really  due  to  the  daily  rotation  of  the  earth 
on  its  axis.  Here  he  breaks  entirely  new  ground  in  his  treatment 
of  motion.  His  great  discovery,  w^hich  threw-  a  new  light  on  the 
mechanics  of  the  solar  system,  was  substantially  Newton's  first 
law  of  motion — '  Every  body  continues  in  its  state  of  rest  or  of 
uniform  motion  in  a  straight  line,  except  in  so  far  as  it  is  compelled 
by  force  applied  to  it  to  change  that  state  '.  Putting  aside  any 
discussion  of  this  '  force  ',  a  conception  first  defined  by  Newton, 
and  only  imperfectly  grasped  by  Galileo,  we  may  interpret  the 
law  as  meaning  that  a  body  has  no  more  inherent  tendency  to 
diminish  its  motion  or  to  stop  than  it  has  to  increase  its  motion 
or  to  start,  and  that  any  alteration  in  either  speed  or  direction 
is  to  be  explained  by  the  action  on  it  of  some  other  force.  As  it 
is  impossible  to  isolate  a  body  from  all  others,  we  cannot  experi- 
mentally realize  the  state  of  things  in  \vhich  it  goes  on  moving 
indefinitely  in  the  same  direction  and  at  the  same  rate  ;  it  may, 
however,  be  shown  that  the  more  we  remove  it  from  external 


THE  SCIENTIFIC  W0RK8  OF  GALILEO  263 

influence  the  less  alteration  there  is  in  its  motion.  Galileo 
illustrates  this  idea  by  a  ball  on  an  inclined  ])lane.  If  the  ball 
is  projected  upwards  its  motion  is  retarded  ;  if  downwards  it  is 
continually  accelerated.  This  is  true  if  the  plane  be  fairly  smooth 
and  the  inclination  not  very  small.  If  now  we  imagine  the 
experiment  performed  on  an  ideal  plane,  which  is  perfectly 
smooth,  we  should  expect  the  same  results,  however  small  the 
inclination.  Consequently,  if  the  plane  be  quite  level,  so  that 
there  is  no  distinction  between  up  and  down,  we  should  expect 
the  motion  to  be  neither  retarded  nor  accelerated,  but  to  continue 
without  alteration. 

Other  more  familiar  examples  are  given  of  the  tendency  of 
a  body  when  once  in  motion.  This  principle  of  motion  being 
once  established,  it  becomes  easy  to  deal  with  several  common 
objections  to  the  motion  of  the  earth.  The  case  of  a  stone  dropped 
from  the  top  of  a  tower,  which,  if  the  earth  be  moving  rapidly 
from  west  to  east,  might  be  expected  to  fall  to  the  west,  is  com- 
pared to  that  of  a  stone  dropped  from  the  masthead  of  a  mo\^ng 
ship.  It  is,  therefore,  entirely  in  accord  with  theory  that  the 
stone  should  fall  as  it  does  at  the  foot  of  the  tower. 

No  objections  to  the  hypothesis  of  the  earth's  rotation  being 
found  tenable,  it  is  shown  by  Salviati  how  much  more  simple  is 
the  real  motion  proposed  than  the  supposition  that  the  universe 
revolves  daily  round  a  fixed  earth.  '  To  make  the  iniiverse 
revolve ',  he  says,  '  in  order  to  maintain  the  immobility  of  the 
earth  is  as  little  reasonable  as  to  require,  in  order  to  see  Venice 
from  the  top  of  the  Campanile,  that  the  whole  panorama  should 
move  round  the  spectator  instead  of  his  simply  moving  his 
head.' 

The  primitive  notion  of  the  stars  as  fixed  in  a  crystal  sphere 
had  been  long  overthrown.  And,  supposing  that  they  were 
distinct  and  independent  bodies,  it  was  difficult  to  imagine  laws 
controlling  their  motion  about  a  fixed  earth  that  should  result  in 
revolutions  timed  uniformly  for  all  and  at  the  same  time  of 
enormous  rapidity.  Salviati  makes  the  improbable  practically 
impossible  by  referring  to  the  phenomenon  now  known  as  the 
*  precession  of  the  equinoxes  ',  in  virtue  of  which  the  direction 
of  the  earth's  axis  in  space  moves  slowly,  completing  a  revolution 
in  about  26,000  years.  As  a  consequence  of  this  change,  some  of 
those  stars,  which  in  Ptolemy's  time  were  describing  very  small 

S  2 


2()1  THK  SCIENTIFIC   WORKS   OF  OxVLlLEO 

circles  and,  tlicrcforo,  moving  very  slowly,  muKt  now  be  describing 
larger  circ^les  at  a  greater  speed,  and  vice  versa.  Tiie  system  of 
stellar  motions  that  would  bo  neceHsary  to  account  for  all  this 
would  be  inconceivably  complex,  whereas,  on  the  Copernican 
theory,  they  are  adequately  ex|)laincd  by  the  rotation  of  the 
earth  and  a  simj)le  displacement  of  its  axis  of  rotation. 

A  great  part  of  the  third  Day  is  devoted  to  the  question  of 
stellar  parallax.  In  this  lay  one  of  the  most  serious  objections 
to  the  Co])ernican  theory.  If  it  was  true  that  the  earth  swept 
round  the  sun  in  an  orbit  some  two  hundred  million  miles  across, 
then  it  must  follow  that  at  one  time  of  the  year  we  should  get 
a  different  view  of  the  arrangement  of  the  stars  from  that  obtained 
six  months  later,  when  the  earth  was  at  the  opposite  })oint  of  its 
orbit.  The  nearer  stars  should  undergo  displacements  in  their 
apparent  positions  relative  to  those  more  distant.  The  answer  to 
this  was  that  these  displacements  probably  did  take  place,  but 
were  too  minute  to  be  detected.  But  this  answer,  though  strictly 
true,  implied  that  the  distances  of  even  the  nearest  stars  were 
great  beyond  all  comprehension  ;  and  this  in  turn  implied  that 
the  visible  size  of  the  stars  indicated  a  real  size  of  inconceivable 
dimensions.  The  latter  difficulty  was  reduced  by  Salviati's  asser- 
tion that  the  visible  size  of  a  star  was  an  optical  illusion  ;  the 
telescope  showed  the  stars  to  be  sharp  points,  in  contrast  to  the 
planets  which  though  small  to  the  eye  really  did  possess  visible 
dimensions.  But  the  former  difficulty  remained,  and  nearly  two 
centuries  passed  before  Bessel  made  the  first  rough  measurement  of 
a  stellar  parallax.  His  method  was  essentially  that  suggested  in  the 
Dialogue,  though  the  results  obtained  indicated  for  the  star  61  Cygni 
a  distance  which  would  have  astonished  even  Galileo  himself. 

Towards  the  end  of  the  third  Day  reference  is  made  to  an 
annual  rotation  of  the  earth  about  an  axis  perpendicular  to  the 
plane  of  its  motion,  as  postulated  by  Copernicus.  But  this  third 
rotation  is  an  unnecessary  complication  introduced  by  confusion 
in  geometrical  thought.  That  the  actual  state  of  things  is  quite 
simple  Salviati  illustrates  by  a  reference  to  the  motion  of  a  ball 
floating  in  a  basin  of  water.  If  the  basin  be  held  in  the  hand, 
the  ball  floating  at  or  near  the  centre,  and  the  experimenter  turn 
round  steadily  on  his  feet,  holding  the  basin  in  front  of  him,  the 
ball  remains  in  a  position  which  is  unaltered  with  reference  to 
the  walls  and  furniture  of  the  room,  although  with  reference  to  the 


THE  SCIENTIFIC  WORKS   OF  GALILEO  265 

man  supporting  the  basin  it  might  be  said  to  have  spun  once 
completely  round.  And  so  with  regard  to  the  annual  rotation 
spoken  of  by  Copernicus,  '  What  other  is  the  earth  than  a  globe 
librated  in  tenuous  and  yielding  air  ?  ' 

The  fourth  Day  is  devoted  to  an  examination  of  the  cause  of 
the  tides,  and  is  a  development  of  his  letter  on  the  same  subject 
to  Cardinal  Orsini  in  1616.  It  is  a  singular  circumstance  that  the 
argument  on  which  Galileo  mainly  relied,  as  furnishing  a  physical 
demonstration  of  the  truth  of  the  Copernican  theory,  rested  on 
a  misconception.  The  tides,  he  says,  are  of  three  kinds — daily, 
monthly,  and  yearly.  The  first  and  principal  ones  are  a  visible 
effect  of  the  terrestrial  double  movement,  since  they  are  the  com- 
bined result  of  (1)  the  earth's  daily  rotation,  and  (2)  the  inequality 
of  the  absolute  velocities  of  the  various  parts  of  the  earth's  surface 
in  its  revolution  round  the  sun.  The  monthly  tides  depend  in 
a  secondary  way  on  the  moon's  motion,  and  the  annual  tides, 
also  in  a  secondary  way,  on  the  sun's  action.  These  bodies, 
according  to  their  positions  relatively  to  the  earth  and  to  each 
other,  produce  inequalities  in  the  earth's  movements,  and  these 
inequahties  are  the  cause  of  the  monthly  and  yearly  tides.  To 
such  notions  Galileo  attached  capital  importance,  and  he  was 
inclined  to  ridicule  Kepler's  suggestion  that  the  attraction  of  the 
moon  was  in  some  way  the  cause  of  the  phenomenon.  The 
influence  of  the  moon  on  the  tides  had  been  recognized  from 
ancient  times,  but  a  scientific  explanation  was  not  to  be  expected 
until  the  law  of  universal  gravitation  had  been  fully  realized. 
Indeed,  even  now,  with  all  the  resources  of  modern  science,  the 
problem  cannot  be  said  to  be  completely  solved. 

This  last  part  of  the  Dialogue  is  therefore  of  little  value,  and 
may  be  passed  over.  The  chief  work  was  to  establish  the  Coperni- 
can theory,  which,  first  promulgated  in  the  days  when  human 
vision  was  unaided,  had  been  found  by  Galileo  to  be  supported 
by  all  the  evidence  that  could  be  gathered  by  means  of  his  tele- 
scope. The  problem — if  it  may  be  still  said  to  exist — takes 
a  different  form  at  the  present  day.  So  far  are  we  now  from  the 
pre-Copernican  theory  of  a  fixed  earth,  that  we  look  upon  no 
single  object  in  the  universe  as  fixed.  The  sun  itself  has  its  motion 
amongst  the  other  visible  stars,  and  the  present  direction  and  rate 
of  that  motion  are  roughly  known.  Accordingly,  the  alternative 
which  offered  itself  to  the  controversialists  of  Galileo's  day,  that 


2()<)  THK  SCIKNTirif   \VOI{KS   OF  (LWAi.KO 

cither  tlic  suii  of  tlic  caith  is  .stationary,  does  not  concern  us  any 
more  ;    both  of  those  bodies  arc  inos  in;j:. 

'.].   (Uiliho's  Second   h' neon  tiler  iritli   the   /nf/iiisidoji. 
His  Trial  and  Ahjn ration,   UV.Vl-A  ' 

The  publication  of  the  Dialoyue  on  the  Tu;o  Chief  Syfitarns  of 
the  World  raised  a  tumult  in  the  ecclesiastical  world,  and  especially 
among  the  Jesuits,  who  now  resolved  to  pursue  the  author  with 
the  utmost  energy.  Tlicy  claimed  the  mono])oly  of  instruction 
and  the  first  rank  in  the  learned  world,  and  were  jealous  of  all 
intruders.  Galileo  was  in  every  way  inconvenient  to  them,  and 
the  more  obnoxious  in  that  he  had  already  measured  swords  with 
distinguished  members  of  the  Order,  Fathers  Scheiner  and  Grassi. 
And  now  appeared  his  Dialogue,  in  which  some  old  sores  are 
reopened.  The  book  was,  therefore,  denounced  as  a  defence  of 
Gopernicanism  under  the  flimsiest  of  disguises,  as  a  gross  violation 
of  the  admonition  and  decree  of  1616,  as  an  insult  to  the  Pope 
himself.  He  was  Simplicio — the  Simpleton  !  Was  not  his  un- 
answerable argument  of  1624  put  into  the  mouth  of  a  simpleton, 
dragged  in  at  the  end,  and  summarily  dismissed  with  a  pious 
ejaculation  ?  Galileo  w^as  charged  with  daring,  after  solemn 
warning,  to  interpret  the  Scriptures  to  his  own  ends.  It  was 
bad  enough,  they  said,  to  upset  the  old  beliefs  and  spoil  the  face 
of  nature  with  his  celestial  novelties,  but  at  least  he  must  be 
taught  to  leave  the  Bible  alone.  In  this  he  was  rebellious  against 
Mother  Church,  and,  further,  deceitful  in  that  he  obtained  the 
Imprimatur  by  suppressing  material  facts  in  his  dealings  with  the 
censors.  Although  the  safety  of  the  Church  and  the  vindication 
of  its  decrees  w^ere  the  ostensible  reasons  for  the  subsequent 
proceedings,  it  would  not  be  far  from  the  truth  to  say  that  revenge 
for  an  assumed  insult  was  the  primary  and  determining  factor. 
Urban  VIII  and  many  of  the  high  dignitaries  of  the  Church,  if 
not  Copernicans  at  heart,  were  indifferent  and  cared  little  one 
way  or  the  other.-  As  regards  the  Pope  himself,  we  have  seen 
evidence  of  his  affection  for  Galileo  and  of  his  liberal  sentiments, 
of  his  relish  for  the  works  on  Sun-spots,   on  Floating  Bodies, 

1  Cf.  Xat.  Ed.,  vol.  xiv,  pp.  372,  402  ;  vol.  xvi,  various  :  vol.  xix,  pp.  272-421. 

-  Even  members  of  the  Collegio  Romano,  including  his  old  antagonists 
Fathers  Scheiner  and  Grassi,  were  Copernicans  in  disguise.  Cf.  Favaro's  Adver- 
saria Galileiana,  Serie  Seconda,  Padova,  1917,  p.  27. 


THE  SCIENTIFIC  WORKS  OF  GALILEO  267 

11  Saggiatore,  &c.  Tlieii,  we  have  his  statements  (1)  that  the 
Copernican  doctrine  is  not  heretical  but  only  rash,  and  (2)  that  if 
it  rested  with  him  the  decree  of  1616  would  never  have  been  issued. 
All  this  seems  to  show  that,  if  the  question  of  a  personal  insult  had 
not  arisen,  the  Dialogue  would  at  the  worst  have  been  put  on  the 
Index,  as  was  the  book  of  Copernicus,  in  1616,  '  until  corrected'. 
Early  in  August,  1632,  the  sale  of  the  book  was  proliibited 
and  its  contents  submitted  to  a  special  commission,  who  reported, 
after  a  month's  session  : 

'  1.  Galileo  has  transgressed  orders  in  deviating  from  the  hypo- 
thetical standpoint,  by  maintaining  decidedly  that  the  earth  moves 
and  that  the  sun  is  stationary.  2.  He  has  erroneously  ascribed 
the  phenomena  of  the  tides  to  the  stability  of  the  sun  and  the 
motion  of  the  earth,  which  are  not  true.  3.  He  has  been  deceit- 
fully silent  about  the  command  laid  upon  him  in  1616,  viz.  to 
relinquish  altogether  the  opinion  that  the  sun  is  the  centre  of  the 
world  and  immovable  and  that  the  earth  moves,  nor  henceforth 
to  hold,  teach,  or  defend  it  in  any  way  whatsoever,  verbally  or 
in  writing.' 

On  September  23  Galileo  was  ordered  to  appear  in  the 
course  of  the  following  month  before  the  Commissary-General 
of  the  Holy  Office  in  Rome.  His  friends  pleaded  his  age  and 
infirmities  and  the  inclemency  of  the  season,  and  begged  that  he 
might  therefore  be  interviewed  in  Florence,  but  to  no  purpose. 
'  In  Rome  he  must  appear,  and  as  a  prisoner  in  chains  if  he  will 
not  come  willingly ',  came  the  answer.  To  avert  the  most  extreme 
measures  the  Grand  Duke  caused  him  to  be  informed  (January  11, 
1633)  that  it  was  at  last  necessary  to  obey  the  orders  of  the 
supreme  authorities  at  Rome,  and,  in  order  that  he  might  perform 
the  journey  more  comfortably,  Grand-ducal  litters  and  a  trust- 
worthy guide  would  be  placed  at  his  disposal,  and  he  would  be 
lodged  in  Rome  in  the  house  of  the  Grand  Duke's  Ambassador. 
The  pitiful  impotence  of  an  Italian  ruler  of  that  day  in  face  of 
the  Roman  Church  is  painfully  obvious  in  this  decision.  The 
Sovereign  does  not  dare  to  protect  his  subject — even  his  old  and 
respected  tutor,  but  gives  him  up  to  the  Inquisition,  as  if  he  were 
an  alien  malefactor.^ 

1  The  Venetian  Republic  was  the  only  State  in  Italj'  that  would  have  asserted 
its  independence,  as  it  had  often  done,  and  would  have  refused  to  hand  over  one 
of  its  officials  to  the  Roman  power.  Indeed,  when  these  proceedings  began, 
Francesco  ]Morosini  of  Venice  offered  to  reinstate  him  in  his  old  chair  at  Padua 
on  any  conditions  that  he  chose  to  make,  and  to  print  his  Dialogue  in  Venice. 


268  THE  SCIENTIFIC  WORKS  OF  GALILEO 

On  .Iftiuiary  20,  1633,  he  loft  Florence,  Iialted  twenty  dayH  i]i 
great  discomfort  at  the  frontier  on  account  of  quarantine,  and 
arrived  in  Rome  on  February  L3.  For  the  next  four  nioiitlis  tlie 
juoceedingrt  dragged  on.  He  himself  was  inclined  to  hold  out, 
his  friends  besought  him  to  submit,  he  was  ruthlessly  haled 
backwards  and  forwards  by  his  judges,  questioned  here  and 
threatened  there — the  threat  being  a  '  rigorous  examination  ', 
an  eui)hemism  for  physical  torture.  At  last,  on  June  22,  sentence 
was  pronounced,  and  Galileo  made  his  pitiful  abjuration.  After 
setting  out  in  detail  his  various  delinquencies,  the  Inquisitors 
conclude : 

'  Therefore,  having  seen  and  maturely  considered  the  merits 
of  your  case,  with  your  confessions  and  excuses,  and  everything 
else  which  ought  to  be  seen  and  considered,  we  pronounce,  judge, 
and  declare  that  you  have  rendered  yourself  vehemently  suspected 
by  this  Holy  Office  of  heresy,  in  that  (1)  you  have  believed  and 
held  the  doctrine  (which  is  false  and  contrary  to  the  Holy  and 
Divine  Scriptures)  that  the  sun  is  the  centre  of  the  world  and  that 
it  does  not  move  from  east  to  west,  and  that  the  earth  does  move 
and  is  not  the  centre  of  the  world  ;  and  (2)  that  an  opinion  can 
be  held  and  defended  as  probable  after  it  has  been  decreed  con- 
trar}^  to  the  Holy  Scriptures,  and,  consequently,  that  you  have 
incurred  all  the  censures  and  penalties  enjoined  in  the  sacred 
canons  and  other  general  and  particular  codes  against  delinquents 
of  this  description.  From  this  it  is  Our  pleasure  that  you  be 
absolved  provided  that,  with  a  sincere  heart  and  unfeigned  faith, 
in  Our  presence  you  abjure,  curse,  and  detest  the  said  errors  and 
heresies,  and  every  other  error  and  heresy  contrary  to  the  Catholic 
and  Apostolic  Church  of  Rome,  and  in  the  form  that  shall  be 
prescribed  to  you.  But  that  your  grievous  and  pernicious  error 
may  not  go  altogether  unpunished,  and  that  you  may  be  more 
cautious  in  future,  and  as  a  warning  to  others  to  abstain  from 
delinquencies  of  this  sort.  We  decree  that  the  book  Dialogue  of 
Galileo  Galilei  be  prohibited  by  public  edict,  and  We  condemn 
you  to  the  prison  of  this  Holy  Office  for  a  period  determinable 
at  Our  pleasure,  and  by  way  of  salutary  penance  We  order  you 
during  the  next  three  years  to  recite,  once  a  week,  the  seven 
penitential  psalms,  reserving  to  Ourselves  the  power  of  moderating, 
commuting,  or  taking  off  the  whole  or  part  of  the  said  punishment 
or  penance.' 

In  conformity  with  this  sentence,  Galileo  was  made  to  kneel 
before  the  Inquisition,  and  make  the  following  abjuration  : 

'  I,  Galileo  Galilei,  son  of  the  late  Vincenzio  Galilei  of  Florence, 


THE  SCIENTIFIC  WORKS  OF  GALILEO  269 

aged  seventy  years,  being  brought  personally  to  judgement,  and 
kneeling  before  you.  Most  Eminent  and  Most  Reverend  Lord 
Cardinals,  General  Inquisitors  of  the  Universal  Christian  Republic 
against  heretical  depravity,  and  having  before  my  eyes  the  Holy 
Gospels  which  I  touch  with  my  own  hands,  swear  that  I  have 
always  believed,  and,  with  the  help  of  God,  will  in  future  believe 
every  article  which  the  Holy  Catholic  and  Apostolic  Church  of 
Rome  holds,  preaches,  and  teaches.  But  because  I  have  been 
enjoined  by  this  Holy  Office  altogether  to  abandon  the  false 
opinion  that  the  sun  is  the  centre  and  immovable,  and  been 
forbidden  to  hold,  defend,  or  teach  the  said  false  doctrine  in  any 
manner  ;  and  because,  after  it  had  been  signified  to  me  that  the 
said  doctrine  is  repugnant  to  the  Holy  Scripture,  I  have  A\Titten 
and  printed  a  book,  in  which  I  treat  of  the  same  condemned 
doctrine,  and  adduce  reasons  with  great  force  in  support  thereof 
without  giving  any  solution,  and  therefore  have  been  judged 
grievously  suspected  of  heresy,  that  is  to  say,  that  I  held  and 
believed  that  the  sun  is  the  centre  of  the  world  and  immovable, 
and  that  the  earth  is  not  the  centre  and  js  movable,  I  am  willing 
to  remove  from  the  minds  of  your  Eminences,  and  of  every 
Catholic  Christian,  this  vehement  suspicion  rightly  entertained 
towards  me.  Therefore,  with  a  sincere  heart  and  unfeigned  faith, 
I  abjure,  curse,  and  detest  the  said  errors  and  heresies,  and 
generally  every  other  error  and  heresy  contrary  to  the  said  Holy 
Church,  and  I  swear  that  I  will  never  more  in  future  say,  or  assert 
anything,  verbally  or  in  writing,  which  may  give  rise  to  a  similar 
suspicion  of  me  ;  and  that  if  I  shall  know  any  heretic,  or  any 
one  suspected  of  heresy,  I  will  denounce  him  to  this  Holy  Office, 
or  to  the  Inquisitor  and  Ordinary  of  the  place  in  which  I  may  be. 
I  swear,  moreover,  and  promise  that  I  will  fulfil  and  observe  fully 
all  the  penances  which  have  been  or  shall  be  laid  on  me  by  this 
Holy  Office.  But  if  it  shall  happen  that  I  violate  any  of  my  said 
promises,  oaths,  and  protestations  (which  God  avert),  I  subject 
myself  to  all  the  pains  and  punishments  which  have  been  decreed 
and  promulgated  by  the  sacred  canons  and  other  general  and 
particular  constitutions  against  delinquents  of  this  description. 
So,  may  God  help  me,  and  these  His  Holy  Gospels  which  I  touch 
with  my  own  hands. 

'  I,  the  above-named  Galileo  Galilei,  have  abjured,  sworn,  pro- 
mised, and  bound  myself  as  above,  and,  in  witness  thereof,  with 
my  own  hand  have  subscribed  this  my  abjuration,  which  I  have 
recited  word  for  word,  in  Rome,  in  the  Convent  of  Minerva,  this 
22nd  June,  1633.  I,  Galileo  Galilei,  have  abjured  as  above  with 
my  own  hand.' 

While  the  older  wTiters  generally  go  to  one  extreme  and  say 
that  Galileo  was  tortured,  thrown  into  a  dungeon  for  years,  or 


27(>  THK  SCIKXTIFIC   WOKKS   OF  (IWAl.KO 

lor  the  iTst  of  his  life,  and  was  in  pliy.sical  fact  a  martyr,  some 
recent  authors  have  <r()\n'  to  tlic  other  extreme,  and  aver  that  he 
liad  no  chiim  to  much  sym|)atliy,  that  he  liad  hron<jlit  his  troul)les 
on  himself  l)y  want  of  tactt  and  temper.  Otiiers,  again,  hhime 
him  for  not  '  seeing  this  thing  througli  '.  Fkewster,  for  exam):)le, 
compares  Inm  to  the  ('hristiaii  martyrs,  and  finds  him  sadly 
degenerate.  '  Had  Galileo  ',  he  says,  '  but  added  the  courage  of 
the  martyr  to  the  wisdom  of  the  sage  ;  had  he  carried  the  glance 
of  liis  indignant  eye  round  the  circle  of  his  judges  ;  had  he  Hfted 
his  hands  to  Heaven,  and  called  on  the  living  God  to  witness  the 
truth  and  immutability  of  his  opinions,  the  bigotry  of  his  enemies 
would  liave  been  disarmed,  and  Science  would  have  enjoyed 
a  memorable  triumph.'  Perhaps  ;  but  perhaps,  on  the  other 
hand,  his  judges,  instead  of  being  cowed  by  the  glance  of  his  eye, 
would  have  delivered  him  to  the  stake,  as  they  did  Giordano 
Bruno  earlier  in  the  century  (1600),  and  Marc'  Antonio  de  Dominis 
only  eight  years  before.  Revealed  truth  may  require  its  martyrs, 
and  perhaps  the  blood  of  the  martyrs  may  be  the  seed  of  the 
Church,  but  scientific  truth  is  not  thus  established.^ 

After  his  sorrowful  drama  had  concluded,  Galileo  was  led  back 
to  the  buildings  of  the  Holy  Office.  And  now  that  he  and  the 
Copernican  theory  were  condemned  with  all  the  terrifying  forms 
of  the  Inquisition,  the  Pope's  wounded  vanity  was  soothed,  and 
he  gave  the  word  for  a  little  mercy.  Galileo  was  not  to  be  kept 
in  the  prison  of  the  Holy  Office,  but  was  banished  to  the  villa  of 
the  Grand  Duke  of  Tuscany  at  Trinita  dei  Monti,  which  he  was 
to  consider  as  a  prison.  A  week  later  he  was  allowed  to  retire 
to  Siena  to  the  palace  of  Archbishop  Ascanio  Piccolomini  (a  former 
pupil  in  Padua),  where  he  was  to  remain  under  the  orders  of  the 
Archbishop,  and  on  no  account  to  leave  the  house,  except  to  hear 
mass,  without  permission  from  Rome. 

He  was  informed  of  this  decision  on  July  2,  and  early 
on  the  6tli  he  shook  the  dust  of  Rome  from  ofi  his  feet.  He 
reached  Siena  on  the  9th  and  was  warmly  received  by  Piccolomini 
and  other  friends  :  but  kindness  could  not  make  him  forget  that 
lie  was  a  prisoner.  As  the  weary  months  rolled  on,  the  old  man 
became  a  little  resigned  to  the  situation,  and  began  to  occupy 

1  Cf.  Bruno  and  Galileo,  Quarterly  Revieic,  1878,  No.  290,  p.  362,  a  Plutarchian 
contrast  by  John  Wilson. 


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272  THK  SCIENTJFK.'   WORKS   OF  (MLILEO 

him.self  with  auollici-  ol  his  great  works,  Dlahxjhl  chile  Nuove 
Scienze,  the  writing  of  which  he  spoke  of  as  far  back  as  1610,  in 
Ills  letter  to  Vinta. 

ill  November,  1033,  thinking  tlio  time;  favoura}>le,  ilie  Tuscan 
Ambassador  in  Homo  began  to  move  for  a  fn^e  pardon,  })ut  th(; 
Pope  was  not  disposed  to  go  so  far,  and  pretended  there  would 
be  a  difficulty  in  getting  the  consent  of  the  Holy  Office — a  patent 
evasion,  as  the  decision  rested  solely  with  himself.  At  length,  on 
December  1,  1633,  the  question  of  i)ardoji  or  ratlier  release 
from  personal  restraint  came  before  the  Congregation,  the  Pope 
presiding.  It  was  refused,  but  GaHleo  was  allowed  to  retire 
to  his  villa  at  Arcetri,  near  Florence,  .where  he  was  to  remain  till 
further  orders. 

V.    Declining  Years  (1634-42) 
1.  Dialoghi  delle  Nuove  Scienze  ^ 

The  Dialogues  on  the  New  Sciences  (  (1)  on  coherence  and 
resistance  to  fracture,  and  (2)  on  uniform,  accelerated,  and  violent 
or  projectile  motions)  were  begun  in  Siena  in  1633,  and  were 
completed  by  the  end  of  1634.  After  the  condemnation  in  1633, 
the  Holy  Office  placed  Galileo's  name  on  the  list  of  authors  whose 
writings  edita  et  edenda  were  strictly  forbidden.  Galileo  tried  to 
publish  at  Vienna,  only  to  find  that  all  books  printed  there  must 
be  approved  by  the  Jesuits,  amongst  whom  happened  to  be  Father 
Scheiner.  He  tried  Olmiitz  and  Prague,  but  at  each  place  licensing 
and  other  difficulties  cropped  up.  Finally  he  opened  direct 
negotiations  with  the  Elzevirs,  and  the  work  was  issued  from  their 
press  at  Ley  den  early  in  1638.^ 

The  Dialoghi  delle  Nuove  Scienze  is  practically  a  compendium, 
with  later  additions,  of  his  early  mechanical  w^ork  in  Pisa  and  Padua, 
and  rightly  did  he  call  it,  in  his  letter  to  Vinta  of  May  7,  1610,  a 
new  science  invented  by  himself  from  its  very  first  principles. 

'  Dynamics',  says  Lagrange,  '  is  a  science  due  entirely  to  the 
moderns,  and  Galileo  is  the  one  who  laid  its  foundations.  Before 
him  philosophers  considered  the  forces  which  act  on  bodies  in 

1  Cf.  Nat.  Ed.,  vol.  viii,  pp.  12  et  seq.  ;  vol.  xiv,  p.  386  ;  vol.  xv,  pp.  248,  257, 
284     vol.  xvi,  pp.  59,  72. 

2  See  Fig,  11.  In  order  to  obviate  trouble  with  the  Holy  Office,  he  pretended 
that  the  book  was  pirated  from  a  manuscript  copy,  which  he  had  given  to  Comte 
de  Noailles  (lately  French  Ambassador  in  Rome),  to  whom  it  is  dedicated. 


THE  SCIENTIFIC  WORKS  OF  GALILEO  273 

a  state  of  equilibrium  only,  and,  although  they  attributed  in 
a  vague  way  the  acceleration  of  falling  bodies  and  the  curvilinear 
movement  of  projectiles  to  the  constant  action  of  gravity,  nobody 
had  yet  succeeded  in  determining  the  laws  of  these  phenomena. 
Galileo  made  the  first  important  steps,  and  thereby  opened  a  way, 
new  and  immense,  to  the  advancement  of  mechanics  as  a  science.'^ 

In  this  new  dialogue  the  discussion  is  carried  on  by  the  same 
speakers  as  in  the  Dialogue  of  1632.  The  first  two  Days  are 
mainly  concerned  with  the  resistance  of  solids  to  fracture,  and 
the  cause  of  their  coherence.  Their  scientific  value  lies  in  the 
incidental  experiments  and  observations  on  motion  through 
resisting  media.  The  debate  opens  with  an  examination  of  the 
current  belief  that  machines  built  on  exactly  similar  designs,  but 
on  different  scales,  were  of  strength  in  proportion  to  their  linear 
dimensions.  It  is  shown  that  the  larger  machine  will  equal  the 
smaller  in  all  respects,  except  that  it  will  not  be  so  strong  or  so 
resistant  to  violent  actions.  After  explaining  the  strength  of 
ropes  made  of  fibrous  or  filamentous  materials,  he  comes  to  the 
cause  of  coherence  of  the  parts  of  such  things  as  stones  and 
metals,  which  do  not  show  a  fibrous  structure.  Presently,  Salviati 
asks  what  is  the  nature  of  the  force  that  prevents  a  glass  or  metal 
rod,  suspended  from  above,  being  broken  by  its  own  weight  or 
by  a  pull  at  the  free  end  ?  No  satisfactory  explanation  is  forth- 
coming ;  but  that  suggested  depends  upon  nature's  so-called 
repugnance  to  a  vacuum,  such  as  is  momentarily  produced  by 
the  sudden  separation  of  two  flat  surfaces.  This  idea  is  extended, 
and  a  cause  of  coherence  is  found  by  considering-  every  body  as 
composed  of  very  minute  particles,  between  any  two  of  which  is 
exerted  a  similar  resistance  to  separation. 

This  leads  to  an  experiment  for  measuring  what  is  called  the 
force  of  a  vacuum.  The  experiment  occasions  a  remark  from 
Sagredo  that  his  lifting-pump  would  not  work  when  the  water 
had  sunk  to  the  depth  of  35  feet  below  the  valve.  This  story  is 
sometimes  told  as  if  Galileo  had  said  jokingly  that  nature's  horror 
of  a  vacuum  does  not  extend  beyond  35  feet ;  but  it  is  plain 
that  the  remark  was  made  seriously.  He  held  the  then  current 
notion  of  suction,  for  he  compares  the  column  of  water  to  a 
rod  of  metal  suspended  from  its  upper  end,  which  may  be 
lengthened  till  it  breaks  with  its  own  weight.  It  is  extra- 
ordinary that  he  failed  to  see  how  simply  this  phenomenon  could 
^  Mechanique  analytique,  Paris,  1788. 


274  'PHK   SCIKN'riKIC   \V()IM\S   OF  (iALILKO 

hv  explained  l)y  Uw  weight  of  tlic  at niospliore,  with  which  he  was 
well  acquainted.' 

We  come  next  to  the  violent  efTects  of  heat  and  light.  It  is 
KU^gestcd  tliat,  perhaps,  heat  dissolves  ])odie.s  by  insirniatinjz  its(^lf 
between  their  miinite  particles.  The  effects  of  lightnin<^  are 
mentioned  and  experiments  with  burning-glasses  referred  to. 
Then  as  regards  light,  Sagredo  asks  whether  its  effect  does  or 
does  not  require  time.  Simplicio  is  ready  with  an  answer — that 
the  discharge  of  artillery  proves  the  transmission  of  liglit  to  be 
instantaneous,  to  which  Sagredo  cautiously  replies  that  nothing 
can  be  gathered  from  that  observation  except  that  light  travels 
more  swiftly  than  sound  ;  nor  can  we  draw  any  decisive  con- 
clusion from  the  rising  of  the  sun.  Who  can  assure  us  that  he 
is  not  in  the  horizon  before  his  rays  reach  our  eyes  ? 

We  next  come  to  Aristotle's  ideas  on  motion  in  pleno  and  in 
vacuo,  and  especially  his  assertion  that  bodies  fall  with  velocities 
])roportional  to  their  weights  and  inversely  proportional  to  the 
densities  of  the  media  through  which  they  are  moving.  This 
proposition  is  examined  in  a  strict  scientific  method.  Heavy 
bodies  of  different  weights  are  dropped  in  air  to  .test  the  truth  of 
the  first  ]3art  of  the  statement ;  and  afterwards  the  motion  of 
bodies  rising  or  falling  in  liquids  is  considered  ;  the  result  being 
to  substitute  for  Aristotle's  assumption  that  law  of  the  motion  of 
falling  bodies  which  is  the  foundation  of  the  science  of  dynamics. 

After  having  discussed  the  first  point  and  shown  that  the  rate 
of  fall  is  not  proportional  to  weight,  Salviati  proceeds  to  examine 
the  motion  of  bodies  sinking  or  rising  in  water  and  other  liquids  ; 
and  brings  forward  experimental  facts  which,  viewed  in  the  light 
of  Aristotle's  statement,  form  a  mass  of  contradiction.  Putting 
then  this  antiquated  theory  aside,  Salviati  inquires  what  is  meant 
by  the  rising  of  some  bodies  in  a  medium,  and  shows  that  only 
those  bodies  rise  which  are  lighter  than  the  medium.  The  rising 
of  an  inflated  bladder  in  the  air  suggests  that  the  atmosphere  must 
have  weight.  Simplicio's  assertion  that  it  is  on  the  contrary  the 
bladder  in  this  case  that  has  levity  is  trivial,  and  is  immediately 
disproved.  Continuing  his  line  of  argument,  Salviati  points  out 
that  the  question  of  rising  or  falling  depends  on  the  gravity  of 
the  medium  as  compared  with  that  of  the  moving  body  ;  further, 
that  when  the  motion  of  the  body,  either  upAvards  or  downwards, 
1  Nat.  Ed.  xi.  12,  and  xii.  33. 


THE  SCIENTIFIC  WORKS  OF  GALILEO  275 

has  once  commenced,  the  different  media  offer  different  resistances 
to  the  motion,  the  heavier  media,  such  as  quicksilver  and  water, 
interfering  more  than  air.  We  are  thus  led  to  the  bold  deduction 
'  that  if  the  resistance  of  the  media  be  wholly  taken  away  all 
matter  would  descend  with  the  same  velocity '. 

In  the  concluding  part  of  this  first  Day  the  theory  of  the 
pendulum  is  applied  to  musical  concords  and  discords,  which 
result  from  the  concurrence  or  opposition  of  vibrations  of  the  air 
striking  upon  the  drum  of  the  ear.  These  vibrations  may  be  made 
manifest  by  rubbing  the  finger  round  a  glass  set  in  a  large  vessel 
of  water  ;  '  and,  if  by  pressure  the  note  is  suddenly  made  to  rise 
to  the  octave  above,  every  one  of  the  undulations,  which  will  be 
seen  regularly  spreading  round  the  glass,  will  suddenly  split  into 
two,  proving  that  the  vibrations  that  occasion  the  octave  are 
double  those  belonging  to  the  simple  note '.  Galileo  then  describes 
a  method  he  discovered  by  accident  of  measuring  the  length  of 
these  waves  more  accurately  than  can  be  done  in  the  agitated 
water.  While  scraping  a  brass  plate  with  an  iron  chisel,  he  occa- 
sionally produced  a  hissing  or  whistling  sound,  and  whenever  this 
occurred  he  observed  the  dust  on  the  plate  to  arrange  itself  in 
small  parallel  streaks  equidistant  from  each  other.  In  repeated 
experiments  he  produced  different  tones  by  scraping  with  greater 
or  less  briskness,  and  remarked  that  the  streaks  produced  by 
high  notes  stood  closer  together  than  those  from  low.  Among  the 
sounds  produced  were  two,  which  by  comparison  with  a  viol  he 
ascertained  to  differ  by  an  exact  fifth  ;  and  measuring  the  spaces 
between  the  streaks  he  found  thirty  of  one  equal  to  forty-five  of 
the  other,  which  is  exactly  the  proportion  of  the  lengths  of  strings 
of  the  same  material  which  sound  a  fifth  to  each  other. ^ 

Salviati  also  remarks  that  if  the  sounding  materials  be  different, 
as  for  instance  if  it  be  required  to  sound  an  octave  to  a  note  on 
catgut  on  a  wire  of  the  same  length,  the  weight  of  the  wire  must 
be  made  four  times  as  great,  and  so  on  for  other  intervals. 

Salviati :  '  I  will  now  show  you  an  experiment  from  which  the 
eye  will  derive  a  similar  pleasure.  Suspend  three  balls  of  lead 
by  cords  of  different  lengths,  such  that,  while  the  longest  makes 
two  oscillations,  the  shortest  makes  four,  and  the  medium  three. 
This  will  occur  when  the  longest  string  measures  16  of  any  assumed 

1  This  beautiful  experiment  has  been  largely  used  in  modern  times  by  Chladni, 
Savart,  and  Wheatstone,  with  very  interesting  results. 


27()  I'Hb:  SCIENTIFIC   WORKS   OP  GALILEO 

unit  (inches,  feet,  or  yard.s),  tlic  inediuni  9,  and  the  sliortest  4. 
Now,  pull  these  three  pendulums  aside  and  let  tlieni  go  at  the  same 
instant.  You  will  observe  a  very  curious  interplay  of  the  strings, 
])assing  each  other  in  various  ways,  but  s\ich  tiiat,  at  th(^  coin- 
pletiQU  of  every  fourth  oscillation  of  the  longest  pendulum,  all 
three  arrive  sinniltaneously  at  the  same  terminus,  whence  they 
start  afresh  to  j)crform  the  same  cycle.  This  combination  of 
oscillations  is  ])recisely  that  which  in  music  yields  the  interval  of 
the  octave  and  the  intermediate  fifth.  By  changing  the  lengths 
of  the  cords  in  such  ways  that  their  oscillations  correspond  with 
agreeable  musical  intervals,  we  shall  see  quite  different  crossings, 
but  always  such  that,  after  a  definite  time  and  after  a  definite 
number  of  oscillations  all  the  pendulums  will  reach  the  same 
terminus  at  the  same  moment,  and  then  begin  again  and  so  on. 
If,  however,  the  strings  are  altered  so  that  the  oscillations  are 
incommensurable  and  never  complete  a  series  together,  or  if 
commensurable  complete  the  series  only  after  a  long  interval  and 
after  a  great  number  of  oscillations,  then  the  eye  is  offended  by 
a  disorderly  succession  of  crossing  threads,  just  as  the  ear  is  pained 
by  an  irregular  sequence  of  air  waves.' 

The  second  Day  is  occupied  entirely  with  an  ijivestigation  of 
the  strength  of  beams — an  ampUfication  of  his  researches  on  the 
same  subject  dating  back  to  1609.  Beyond  Aristotle's  remark 
that  long  beams  are  weak,  because  they  are  at  once  the  weight, 
the  lever,  and  the  fulcrum,  nothing  appears  to  have  been  written 
on  the  subject  before  GaUleo  took  it  up.  The  discussion  opens 
with  a  consideration  of  the  resistance  of  solid  bodies  to  fracture. 
This  resistance  is  very  great  in  the  case  of  a  direct  pull,  but  is 
much  less  in  the  case  of  a  bending  force.  Thus,  a  rod  of  glass  or 
iron  will  bear  a  longitudinal  pull  of,  say,  1,000  lb.,  while  50  lb.  will 
break  it  if  it  be  fastened  by  one  end  into  a  wall  or  other  upright 
support.    It  is  this  second  kind  of  strain  that  is  here  discussed. 

'  In  order  to  arrive  at  the  resisting  values  of  prisms  and 
cylinders  of  the  same  material,  whether  alike  or  not  in  shape, 
length,  and  thickness,  I  shall  take  for  granted  the  well-known 
mechanical  principle  of  the  lever,  namely,  that  the  force  bears  to 
the  resistance  the  inverse  ratio  of  the  distances  which  separate 
the  fulcrum  from  the  force  and  resistance  respectively.' 

He  assumed  as  the  basis  of  his  inquiry  that  the  forces  of 
cohesion  with  w^hich  a  beam  resists  a  cross  fracture  in  any  section 
may  all  be  considered  as  acting  at  the  centre  of  gravity  of  the 
section,  and  that  it  breaks  always  at  the  lowest  point.    An  elegant 


I 


THE  SCIENTIFIC   W0RK8   OF  GALILEO  277 

result  deduced  from  this  tlieory  is  that  the  form  of  a  beam,  to 
be  equally  strong  in  every  part,  should  be  that  of  a  parabolic 
prism,  the  vertex  of  the  parabola  being  the  farthest  removed  from 
the  point  of  support.  As  an  easy  way  of  drawing  the  curve  for 
this  purpose,  he  recommends  tracing  the  line  in  which  a  heavy 
flexible  string  hangs  supported  from  two  nails/ 

The  curvature  of  a  beam  under  any  system  of  strains  is  a  sub- 
ject into  which,  before  the  days  of  Newton,  it  was  not  possible  to 
inquire,  and  even  in  the  simpler  problem  considered  by  Galileo 
he  makes  assumptions  which  require  justifying.  His  theory  of 
beams  is  erroneous  in  so  far  as  it  takes  no  account  of  the  equili- 
brium which  must  exist  between  the  forces  of  tension  and  com- 
pression over  any  cross-section. 

In  the  third  Day  we  find  no  new  physical  facts  of  importance, 
and  much  of  the  time  is  taken  up  with  theorems  and  formulae 
deduced  geometrically  from  the  phenomena  of  uniform  and 
accelerated  motion  as  dealt  with  in  the  first  Day.  The  further 
discussion  of  that  subject,  however,  leads  to  a  more  detailed 
statement  of  the  principle  of  inertia ;  but  the  definition  of 
uniformly  accelerated  motion  at  once  introduced  a  difficulty. 
Salviati  gives  the  correct  description  of  it  as  that  of  a  body  which 
moves  in  such  a  manner  that  in  equal  intervals  of  time  it  receives 
equal  increments  of  velocity. 

There  follows  an  interesting  application  of  the  results  obtained. 
He  examines  the  times  of  descent  down  differently  inclined  planes, 
assuming  as  a  postulate  that  the  velocity  acquired  was  the  same 
for  all  planes  of  the  same  height.  This  fact  he  had  verified  by 
careful  experiments,  although  he  was  unable  at  the  time  to  prove 
it  mathematically.' 

The  fourth  Day  plunges  at  once  into  the  consideration 
of  the  '  properties  which    belong   to   a   body   whose    motion  is 

^  This  curve  is  not  strictly  a  parabola,  it  is  now  called  a  catenary  ;  but  it  is 
plain,  from  the  description  of  it  further  on  (in  the  fourth  Day),  that  Galileo  was 
aware  of  this  fact.  The  catenary  resembles  the  parabola,  and,  as  he  justly  re- 
marks, the  resemblance  is  all  the  more  striking  if  the  string  is  so  taut  that  the 
depth  of  the  lowest  point  is  less  than  a  quarter  of  the  distance  between  the  two 
extremities. 

^  Viviani  relates  that,  soon  after  he  joined  Galileo  in  1639,  he  drew  his  master's 
attention  to  this.  The  same  night,  as  Galileo  lay  in  bed,  sleepless  through  indis- 
position, he  discovered  the  necessary  mathematical  demonstration.  It  was  intro- 
duced into  the  subsequent  editions  of  the  Dialogues,  sixth  Day. 

2391  T, 


278  THK  SCFKNTIKIC   WORKS   OF  (JALILEO 

coni|K)uiul('(l  <>1  two  otluT  motions,  one  miiforni,  and  one 
naturally  accclcratod.  'I'liis  is  the  kind  of  motion  seen  in  a  jno- 
jrt'tilo/ 

Aftor  sonic  |)rcliininarv  instruction  in  tiic  proix'rtics  of  the 
parabola,  Salviati  returns  to  the  subject  of  projc^ctiles,  and  lays 
down  the  law  of  the  inde])endence  of  tlie  horizontal  and  th(; 
vertical  motions.  A  body  ])rojectcd  horizontally  would — })ut  for 
its  wei<];ht  and  external  inij)ediments — continue  to  move  in  a 
straiglit  line  ;  and  Salviati  contends  that,  as  tlu;  effects  of  gravity 
acting  by  itself  would  be  entirely  downwards,  gravity  acting  on 
the  projected  body  can  neither  increase  nor  diminish  the  rate 
at  which  it  travels  horizontally.  Therefore,  whatever  be  the 
sha})e  of  the  path  or  the  direction  of  motion  at  any  moment, 
the  distance  travelled  horizontally  may  be  taken  as  a  measure 
of  the  time  that  has  elapsed  since  motion  began.  He  proves 
that  on  this  assumption'  the  path  described  has  geometrical 
properties  Avhich  identify  it  with  the  curve  known  as  the  parabola. 
His  demonstration  is  essentially  that  now  given  in  works  on 
elementary  dynamics. 

After  demonstrating  the  parabolic  nature  of  the  path,  he 
inquires  into  certain  points  of  interest  with  regard  to  it,  and  gives 
proofs  of  many  of  the  elementary  propositions  which  in  modern 
text-books  are  associated  with  parabolic  motion.  He  also  draws 
up  a  table  giving  the  position  and  dimensions  of  the  parabola 
described  wdth  any  given  direction  of  projection,  finding  by  this 
means  what  he  would  have  been  unable  to  give  a  strict  mathe- 
matical proof  of — that  the  range  on  a  horizontal  plane  is  greatest 
when  the  angle  of  elevation  is  45°.^ 

2.    The  Laws  of  Motion 

No  sooner  was  the  manuscript  of  these  dialogues  out  of  his 

hands  (summer  of  1636)  than  Galileo  occupied  himself  with  new 

projects.     '  If   I   live,'   he  wrote  on  July   15,   1636,  to   Berneg- 

ger  of  Strasburg,   '  I  intend  to  put  in  order  a  series  of  natural 

^  '  In  solving  the  problems  of  falling  bodies  and  of  projectiles,  Galileo  was 
essentially  applying  the  principles  of  the  Differential  or  Fluxional  or  Indivisible 
Calculus.  If  pure  mathematics  had  attracted  him  as  strongly  as  its  application 
to  physics,  he  would  have  thought  these  problems  out,  and  Avould  have  founded 
the  Fluxional  Calculus,  which  is  the  glory  of  Newton  and  of  Leibnitz."  Professor 
Jack,  in  Nature,  vol.  xxi,  p.  58. 


THE  SCIENTIFIC  WORKS   OF  GALILEO  279 

and  mathematical  problems  which  I  think  will  be  as  curious  as 
they  are  novel.'  These  were  left  unfinished,  and  now  form  the 
fifth  and  sixth  Days,  which  were  added  to  later  editions  by 
Viviani  after  Galileo's  death/  The  fragment  of  the  fifth  Day  is 
on  the  subject  of  Euclid's  definition  of  ratio  (Book  V,  props.  5 
and  7)  and  was  intended  to  follow  the  first  proposition  on  equable 
motion  in  the  third  Day's  debate.  The  sixth  Day  contains  his 
investigations  on  the  force  of  percussion,  on  which  he  was  employed 
at  the  time  of  his  death. 

'  In  the  last  days  of  his  life  ',  says  Viviani,  '  and  amid  much 
physical  suffering,  his  mind  was  constantly  occupied  with  mechani- 
cal and  mathematical  problems.  He  had  the  idea  of  composing 
two  other  dialogues  to  be  added  to  the  four  already  published. 
In  the  first  he  intended  to  give  many  new  demonstrations  and 
reflections  on  various  passages  in  the  first  four  dialogues,  and  the 
solution  of  many  problems  in  Aristotle's  physics.  In  the  second 
he  proposed  to  discuss,  treating  it  geometrically,  an  entirely  new 
science,  viz.  the  wondrous  force  of  percussion,  which  he  claimed 
to  have  discovered  and  which,  he  said,  exceeded  by  a  long  way  his 
speculations  on  the  same  subject  formerly  published  '  (Nat.  Ed., 
vol.  xix,  Part  ii). 

In  these  admirable  dialogues  Galileo  does  not  formulate  in 
definite  laws  the  interdependence  of  force  and  motion.     This  was 
done  for  the  first  time  by  Newton  at  the  beginning  of  his  Principia 
(1687),   and   hence  they  are  rightly   called   '  Newton's   Laws   of 
Motion  '  ;    but  in  justice  to  Galileo  it  must  be  admitted  that  he 
not  onl}^  prepared  the  way  for  Newton,  but  supplied  him  with 
much  of  Jiis  materials.     Thus,  the  first  law — that  a  body  will 
continue  in  a  state  of  rest,  or  of  uniform  motion  in  a  straight  line, 
until  it  is  compelled  to  change  its  state  by  some  force  imj:)ressed 
upon  it — is  a  generalization  of  Galileo's  theory  of  uniform  motion. 
Since  all  the  motions  that  we  see  taking  place  on  the  surface  of 
the  earth  soon  come  to  an  end,  we  are  led  to  suppose  that  con- 
tinuous movements,  such,  for  instance,  as  those  of  the  celestial 
bodies,  can  only  be  maintained  by  a  perpetual  consumption  and 
a  perpetual  application  of  force,  and  hence  it  was  inferred  that 
rest  is  the  natural  condition  of  things.     We  make,  then,  a  great 
advance  when  we  comprehend  that  a  body  is  equally  indifferent 
to  motion  as  to  rest,  and  that  it  equally  perseveres  in  either  state 
until  disturbing  forces  are  applied. 

1  Cf.  Nat.  Ed.,  vol.  viii,  pp.  321-62. 
T  2 


280  'I'HI':   SCIKX'I'lhIC    WOKKS   OF   CALILKO 

1'lie  socoiul  law — tliat  every  change  of  motion  i.s  in  proportion 
to  the  force  that  inakcK  the  (;hangc,  and  in  the  direction  of  tliat 
straight  Une  in  whicli  the  di.sturhing  force  '\h  inipresHcd — is  involved 
in  (iaUlco's  tlieory  of  projectiles.  Before  his  time  it  was  a  com- 
monly received  axiom  that  a  body  could  not  he  affected  by  more 
than  one  force  at  a  time,  and  it  was  therefore  supposed  that  a 
cannon-ball,  or  other  projectile,  moves  forward  in  a  straight  lin(^ 
until  the  force  which  impelled  it  is  exhausted,  when  it  falls  vertically 
to  the  ground. 

The  establishment  of  this  principle  of  the  composition  of  forces 
supplied  a  conclusive  answer  to  the  most  formidable  of  the  argu- 
ments against  the  rotation  of  the  earth,  and,  accordingly,  we  find 
it  in  the  second  Day  of  the  Dialogue  of  1632.  The  distinction 
between  mass  and  weight  was,  however,  not  noticed,  and,  conse- 
quently, Galileo  failed  to  grasp  the  fact  that  acceleration  might  be 
made  a  means  of  measuring  the  magnitude  of  the  force  producing - 
the  motion.  How  far  he  w^as  from  this  discovery  may  be  gathered 
from  a  remark  by  Salviati,  incidental  to  the  main  argument,  to 
the  effect  that  when  different  bodies  are  falling  freely  towards  the 
earth's  centre,  '  the  difference  of  their  gravities  has  nothing  to 
do  with  their  velocities.' 

Of  the  third  of  the  laws  of  motion — that  action  and  reaction  are 
always  equal  and  opposite — we  find  traces  in  many  of  Galileo's 
researches,  as  in  his  theory  of  the  inclined  plane,  and  in  his  defini- 
tion of  momentum.  It  is  also  adumbrated  in  his  '  Delia  Scienza 
Meccanica  '  (1594),  and  in  his  latest  ideas  on  percussion. 

His  services  were  little  less  conspicuous  in  the  statical  than 
in  the  dynamical  division  of  mechanics.  He  gave  the  first  direct 
and  entirelj"  satisfactory  demonstration  of  equilibrium  on  an 
inclined  plane.  In  order  to  demonstrate  this  he  imagined  the 
weight  and  the  resistance  to  be  applied  to  the  ends  of  a  bent  lever 
whose  arms  w^ere  equal  to  the  vertical  and  slant  sides  of  the 
plane  ;  then  reducing  the  lever  to  a  straight  one  it  was  easy  to 
prove  that  the  forces  in  equilibrio  on  the  jjlane  were  also  in  equili- 
brio  on  the  lever,  and  were  to  one  another  as  the  length  to  the  height 
of  the  plane.  By  establishing  the  theory  of  '  Virtual  velocities ', 
he  laid  down  the  fundamental  principle  w^hich  in  the  opinion  of 
Lagrange  contains  the  general  expression  of  the  laws  of  equilibrium ; 
while  as  regards  that  still  obscure  subject,  molecular  cohesion,  he 
brought  it  for  the  first  time  within  the  range  of  mechanical  theory. 


THE  SCIENTIFIC  WORKS   OF  GALILEO  281 

3.    On  the  Moon's  Lihrations  ^ 

Just  before  his  sight  began  to  fail,-  GaHleo  made  his  last 
astronomical  discovery,  which  is  now  known  as  the  moon's  lihra- 
tions. This  discovery  was  announced  in  letters  to  Fulgenzio 
Micanzio  (November  7,  1637)  and  Alfonso  Antonini  (February  20, 
1638).    To  the  former  he  writes  : 

'  I  have  observed  a  marvellous  appearance  on  the  surface  of 
the  moon.  Though  she  has  been  looked  at  such  millions  of  times 
by  such  millions  of  men,  I  do  not  find  that  any  have  observed 
the  slightest  alteration  in  her  surface  ;  but  that  exactly  the  same 
side  has  always  been  supposed  to  be  presented  to  our  eyes.  Now 
I  find  that  such  is  not  the  case,  but  that  she  changes  her  aspect, 
as  one  who,  having  his  full  face  turned  towards  us,  should  move  it 
sideways,  first  to  the  right  and  then  to  the  left ;  or  should  raise 
and  then  lower  it ;  or,  lastly,  should  incline  it  first  to  the  right 
shoulder,  then  to  the  left.  AH  these  changes  I  see  in  the  moon  ; 
and  the  large,  anciently-known  spots  which  are  seen  on  her  face 
will  help  to  make  evident  the  truth  of  what  I  say.  Add  to  these 
a  further  marvel,  which  is  that  these  three  mutations  have  their 
several  periods — the  first  daily,  the  second  monthly,  the  third 
yearly.' 

Galileo  was  not  long  in  detecting  the  causes  of  the  apparent 
libratory  or  rocking  movement.  The  diurnal  or  parallactic 
hbration  he  saw  was  occasioned  by  our  distance  as  spectators  from 
the  centre  of  the  earth,  which  is  also  the  centre  of  the  moon's 
revolution.  In  consequence  of  this,  as  the  moon  rises  we  get  an 
additional  view  of  the  lower  part  and  lose  sight  of  that  portion  of 
the  upper  part  which  was  visible  while  she  was  low  in  the  horizon. 
The  causes  of  the  other  motions  are  not  so  easily  explained,  nor  is 
it  certain  that  Galileo  himself  understood  them  ;  his  conjecture  of 
a  connexion  with  the  tides  is  certainly  wide  of  the  mark. 

The  moon  in  revolving  round  the  earth  spins  once  on  her  axis, 
so  turning  the  same  side  always  towards  the  earth's  centre.  But 
this  familiar  truth  is  only  approximate.  The  speed  of  rotation  is 
uniform  ;  but  the  speed  of  revolution  in  her  orbit  is  not  so,  because 
that  orbit  is  not  a  circle  but  an  ellipse,  in  which  (as  is  always  the 
ease  with  elliptic  motion)  the  moving  body  travels  faster  while 

»  Cf.  Nat.  Ed.,  vol.  xvii,  pp.  212,  291. 

^  Early  in  1636  his  sight  began  to  fail.    By  the  end  of  June,  1637,  the  sight  of 
the  right  eye  was  gone,  and  early  in  December  following  he  became  totally  blind. 


2S2 


'nii«:  sciioxTiKic  woiiks  ok  caijlko 


near  tlic  (('litre  ot  attraction  lliaii  wlicn  farther  away.  'I'lie  result 
is  that  wv  see  alteniatf^ly  a  little  romul  the  eastern  edge,  and 
a  fortnight  later  a  little  roiiiul  the  western. 

The  two  lihrations,  due  to  independent  causes,  have  approxi- 
niatelv  the  same  |)eri()d— about  one  month.    Their  effects,  h(rw(5ver, 


Fio.  12.     FACSIMILE  OF  UESK^iX  FOK  A  PEXULLUM  CLOCK. 
Drawn  bv  Vincenzio  Galilei  from  his  fathers  dictation. 


1 


vary  according  to  the  changing  position  of  the  earth  in  its  orbit ; 
and  any  particular  phase  of  the  Hbration  is  more  nearly  reproduced 
after  twelve  months  than  after  one.  Galileo  was,  therefore,  justi- 
fied in  suggesting  an  annual  period,  although  it  is  not  customary 
at  the  present  day  to  associate  the  annual  period  with  any  very 
distinct  librations. 


THE  SCIENTIFIC  WORKS   OF  GALILEO  28.S 

4.  Application  of  the  Pendulum  to  Clocks  ^ 
A  few  months  before  his  mortal  illness  Galileo  once  more  gave 
proofs  of  his  mechanical  genius.  It  has  been  remarked  in  the 
progress  of  science  and  scientific  invention  that  the  steps,  which 
on  looking  back  seem  the  easiest  to  make,  are  often  those  which 
are  the  longest  delayed.  The  application  of  the  pendulum  to 
clocks  is  an  instance  of  this.  We  have  seen  that  Galileo  was  early 
convinced  of  the  value  of  the  pendulum  as  a  measurer  of  time,  and 
that  as  far  back  as  1582-3  he  used  it  in  the  Pulsilogia  ;  yet  fifty- 
five  years  later,  although  constantly  using  it  meanwhile,  he  had 
not  devised  a  more  practicable  application  than  that  described 
in  his  letter  of  June  6,  1637,  to  Lorenzo  Realio,  and  in  his 
'  Astronomical  Operations  '  of  1637-8  for  finding  the  longitude 
at  sea. 

'  I  make  use  of  a  heavy  pendulum  of  brass  or  copper,  in  the 
shape  of  a  sector  of  twelve  or  fifteen  degrees,  the  radius  of  which 
may  be  two  or  three  palms  (the  greater  it  is  the  less  trouble  in 
attending  it).  This  sector  I  make  thickest  in  the  middle  radius, 
tapering  gradually  towards  the  edges,  where  I  terminate  it  in 
a  tolerably  sharp  line,  to  obviate  as  much  as  possible  the  resistance 
of  the  air,  which  is  the  main  cause  of  its  retardation.  This  sector 
is  pierced  at  the  centre,  through  which  is  passed  an  iron  bar 
shaped  like  those  on  which  steelyards  hang,  terminated  below 
in  an  angle  or  wedge  which  rests  on  two  bronze  supports.  If  the 
sector  (when  accurately  balanced)  be  removed  several  degrees 
from  the  perpendicular,  it  will  continue  a  to-and-fro  motion 
through  a  very  great  number  of  oscillations  before  coming  to  rest ; 
and  in  order  that  it  may  continue  its  oscillations  as  long  as  it  is 
wanted,  the  attendant  must  occasionalty  give  it  a  push  so  as  to 
carry  it  back  to  large  oscillations. 

'  Now  to  save  the  fatigue  of  continually  counting  the  oscilla- 
tions, this  is  a  convenient  contrivance, — a  small  delicate  needle 
extends  from  the  middle  of  the  sector  which  in  passing  strikes 
a  rod  hung  at  one  end.  The  lower  end  of  this  rod  rests  on  the 
teeth  of  a  horizontal  wheel  as  light  as  paper.  The  teeth  are  cut 
like  those  of  a  saw.  The  rod  striking  against  the  perpendicular 
side  of  a  tooth  moves  it,  but  when  returning  it  slips  over  the 
oblique  side  of  the  next  tooth  and  falls  at  its  foot,  so  that  the  motion 
of  the  wheel  will  be  in  one  direction  only.  By  counting  the  teeth 
j''ou  may  see  at  will  the  number  passed,  and,  consequently,  the 
number  of  oscillations  or  periods  of  time  which  you  wish  to 
measure.    You  may  also  fit  to  the  axis  of  the  wheel  a  second,  with 

1  Cf.  Nat.  Ed.,  vol.  viii,  p.  451  ;   vol.  xvii,  pp.  96,  212  ;   vol.  xix,  pp.  647-59. 


2S4  INK  S(MKNTIFI(:   WORKS   OF  (iAJJLEO 

a  suuvIUm'  iuiiiiImt  ol  tcetli  and  in  j^car  with  a  tliird  wlieel  having 
a  greater  nunihcr  of  t(3oth,  and  so  on.' 

It  was  cliioHy  because  of  the  inadequacy  of  this  nietliod  that 
the  n("gotiati()ns  witli  tlie  States-(j!(Micral  wen^  finally  broken  off. 
Now,  in  the  second  half  of  1641,  it  occurred  to  (jlalikso  that  the 
problem  could  be  solved  by  adding  tin;  pendulum  to  trlie  ordinary 
clock  as  a  regulator  of  its  movements.  He  explained  his  idea  to 
his  son,  N'incenzio,  who  made  a  drawing  (of  wliicli  w(i  reproduce 
a  facsimile,  Fig.  12)  from  his  father's  direction.  Before  the  ]>lan 
could  be  tried  Galileo  fell  ill,  and  died  January  8,  1642.  The 
matter  was  laid  aside,  but  seven  years  after  his  father's  death 
Vincenzio  resumed  it,  and  was  engaged  in  constructing  what 
would  have  been  the  first  pendulum  clock,  when  he,  too,  fell  ill 
and  died,  May  16,  1649.^ 

^  A  working  model  of  this  clock,  inscribed  '  Eustachio  Porcellotti  costruito 
a  Firenze  I'anno  1883  ',  is  in  the  Science  Museum,  South  Kensington,  and  keeps 
very  good  time. 


THE  HISTORY  OF  ANATOMICAL  INJECTIONS 

By  F.  J.  Cole 

'  The  purpose  of  injections,'  says  Robin  with  admirable  brevity, 
'  is  to  make  known  to  us  the  absolute  vascularity  of  the  tissues  '  ; 
and  the  practice  of  the  method,  to  quote  Lacauchie,  '  founded 
an  hundred  reputations,  and  filled  the  museums  with  beautiful 
preparations  '.  The  history  of  a  scientific  method  such  as  this, 
established  alike  by  its  aims  and  results,  may  well  be  traced  in 
some  detail. 

It  will  not  surprise  many  to  learn  that  the  scope  of  this  inquiry 
cannot  be  kept  within  the  terms  of  Robin's  definition.  No  method 
of  scientific  research  long  retains  its  original  character.  The 
further  we  trace  it  back  the  more  it  changes,  until  the  question 
when,  how,  and  with  whom  it  originated  may  indeed  be  debated 
but  not  resolved.  Thus  the  earlier  injections  were  of  a  general 
or  random  character,  and  were  used  to  fill  the  larger  ca^^ties  of 
the  body,  such  as  the  bladder  from  the  penis,  or  to  explore  the 
sohd  inscrutable  bulk  of  tumours.  Afterwards  specific  injections 
into  blood-vessels  were  attempted,  but  even  then  the  endeavour 
was  to  test  or  illustrate  the  doctrine  of  the  circulation,  or  to 
demonstrate  the  local  distribution  of  certain  vessels. 

The  reception  of  the  injection  method  did  not  quite  follow  the 
traditional  course.  The  results  obtained  b}^  it  were  too  obvious 
and  striking  to  be  either  questioned  or  ignored.  Tt  passed  rapidly 
into  general  use,  and  quickly  reached  its  point  of  maximum  utility. 
For  a  time  it  monopolized  attention,  and  its  importance  was  so 
grossly  exaggerated  as  to  countenance  the  belief  that  all  problems 
of  anatomy  and  physiology  might  be  solved  by  its  means. ^  In 
1727  the  French  Academy  of  Science  could  find  no  more  worthy 

1  The  method  is  honoured  by  a  reference  in  Gibbon's  Decline  ami  Fall  (first 
edition,  1788,  vol.  v,  p.  429).  He  saj-s  :  '  A  superstitious  reverence  for  the  dead 
confined  both  the  Greeks  and  the  Arabians  to  the  dissection  of  Apes  and  Quad- 
rupeds ;  the  more  solid  and  visible  parts  were  known  in  the  time  of  Galen,  and 
the  finer  scrutiny  of  the  human  frame  was  reserved  for  the  Microscope  and  the 
Injections  of  modern  artists.' 


2S()      THK   IIISTOKN    OK  AXA'I'O.M  l(    \L   IWIKCTIOXS 

Sliect'ssor  to  Sii'  Isaac  New  Ion  tliaii  l-'rcdcjik  lliiyscli  tlu-  m(;.sl 
famous  injector  ol  liis  time.  How  tuisonnd  conlcniporary  judge- 
ment may  l>c  could  not  have  a  moic  sij^nificant  conlirmation  than 
tlic  verdict  of  |)ost('rity  on  tlie  woiU  of  tliese  two  men — a  verdict 
which  exemplifies  the  practical  wisdom  of  Boyle's  remark  that 
we  are  not  near  so  competent  judges  of  wisdom  as  we  are  of 
justice  and  veracity  \  'I'he  frenzy  for  injections  finally  exhausted 
itself,  and  as  a  means  of  researcli  the  method  may  almost  be  said 
to  have  served  its  purpose,  and  to  have  passed  into  the  shadow 
of  history.  In  stating  this,  however,  certain  modern  develo|)i7ients 
must  not  be  ignored.  In  1886  Camillo  Golgi  introduced  the  intra- 
vitam  method  of  fixing  animal  tissues  by  a  vascular  injection  of 
the  fixative,  and  in  1900  Flint  studied  the  circulation  in  the  living 
embryo  by  throwing  an  injection  into  the  blood-stream. 

There  are  manifestly  several  important  questions  which  the 
injection  method  is  peculiarly  adaj)ted  to  elucidate.  The  circula- 
tion of  the  blood  can  be  demonstrated  beyond  question  by  an 
injection  ex})eriment  ;  the  existence  of  foetal  and  uterine  j)ortions 
in  the  placenta  is  establishable  only  with  the  assistance  of  the 
syringe  ;  the  connexion  of  the  vas  deferens,  epididymis,  and  testis 
is  made  beautifully  clear  by  mercury  injections  ;  and  the  indepen- 
dence of  the  blood  vascular  and  lymphatic  systems  rests  upon 
a  series  of  careful  injections.  Again,  certain  negative  results  may 
claim  attention.  Descartes'  speculation  that  nerve  fibres  were 
valvular  tubes  transmitting  fluid  contents  was  finally  disposed  of 
by  injection  experiments,  in  spite  of  the  fact  that  at  first  such 
support  was  in  some  cases  claimed  for  it.  On  the  other  hand, 
erroneous  views  were  undoubtedly  suggested  and  maintained  by 
the  injections  of  the  earlier  anatomists.  Of  these  lapses  mercury 
was  the  most  frequent  cause,  and  on  that  account  it  is  now  rarely 
if  ever  used.  Even  when  a  mercury  injection  is  successful,  the 
least  abrasion  results  in  an  extensive  bleeding  of  the  mercury, 
and  preparations  so  delicate  were  justly  considered  to  have  but 
a  doubtful  value.  With  other  injection  masses  extravasation 
effects  frequently  resulted  in  serious  error  and  controversy  among 
anatomists,  and  tended  to  bring  the  method  into  disrepute.  The 
disputes  between  the  Hunters  and  the  Monros  owed  something  to 
this  cause,  and  extravasations  into  minute  extra-vascular  spaces 
of  a  tubular  character  explain  the  "  capillicules  '  of  some  of  the 
later  French  injectors. 


THE  HISTORY  OF  ANATOMICAL  INJECTIONS      287 

The  frequent  use  of  the  word  'art '  indicates  an  appreciation  of 
the  beauty  of  the  injected  specimen  by  the  earlier  anatomists, 
and  it  is  easy  to  picture  their  wonder  as  smaller  and  yet  smaller 
vessels  were  disclosed.  What,  therefore,  must  their  delight  have 
been  when,  the  unaided  eye  being  able  to  see  no  more,  the  micro- 
scope revealed  the  amazing  spectacle  of  the  blood  capillaries  in 
all  their  profusion  of  number  and  form.  We  can  scarcely  blame 
them  if  they  abandoned  Science  for  display,  and  injections  were 
undertaken  merely  because  the  result  was  picturesque.  Pole 
says  :  '  The  veins  in  the  kidney  of  a  cat  run  very  superficial, 
and  branch  out  in  a  manner  peculiarly  beautiful,  which  is  the 
only  inducement  to  make  this  preparation,'  And  again,  an 
injected  and  corroded  kidney  of  the  horse  '  makes  a  noble  and 
beautiful  preparation '. 

In  this  article  it  is  not  proposed  to  refer  other  than  briefly  to 
the  injection  of  living  animals,  or  to  the  transfusion  experiments 
which  greatly  occupied  the  attention  of  the  Royal  Society  and 
the  French  Academy  of  Science  in  the  second  half  of  the  seven- 
teenth century.  The  history  and  literature  of  this  subject  has 
already  been  exhaustively  dealt  with,  but  it  does  concern  also  the 
anatomical  application  of  the  injection  method,  and  to  that  extent 
must  receive  attention.  Although  certain  transfusion  and  intra- 
vitam  injections  had  been  attempted  before  the  doctrine  of  the 
circulation  was  established  in  1628,  there  can  be  no  question  that 
Harvey's  work  was  the  fundamental  and  determining  influence  in 
these  early  injection  experiments.  Before  1650,  however,  the  new 
doctrine,  though  indeed  accepted,  had  not  succeeded  in  energizing 
contemporary  investigation,  and  it  was  only  from  this  latter  date 
onwards  that  a  further  advance  is  to  be  noted.  The  period  of 
injection  lies  between  1650  and  1750,  after  which  time  interest 
in  injections  gradually  declined  as  it  was  found  that  the  new 
method  was  unable  to  realize  the  great  expectations  of  its  pro- 
fessors. Ruysch's  activities  are  comprised  between  the  dates  1665 
and  1728,  and  hence  coincide  almost  exactly  with  the  middle  of 
the  injection  period.  The  first  injections,  however,  were  not 
anatomical,  but  were  undertaken  for  physiological  or  medical 
reasons.  The  object  was  to  transfer  blood  from  one  living  animal 
to  another,  and  to  test  the  effect  of  injecting  various  liquids,  drugs, 
or  air  into  the  vessels  of  the  living  body.  Great  hopes  were  b5,sed 
on  these  haphazard  and  ruthless  efforts.     In  1667,  and  again  in 


2SS     riiK  llls^()l:^■  ok  ana  to.mk  \l  ix.ikctions 

1670,  the  Ficncli  Acadciny  coiiductcd  iiuiucroii.s  injection  oxpcri- 
meiits  ill  tlu'  Ixlid  lliat  the  reinvigoratioii  and  even  the  rejuven- 
escence of  ujiinkind  would  hv.  thereby  acconipliwhed,  but  they 
were  (juick  to  acknow  ledge  tlie  vanity  and  futility  of  their  hopes. 
Tlie  faihuT,  iiowever,  was  not  absolute,  for  it  was  soon  perceived 
that  the  humbler  but  still  important  requirements  of  anatomy 
could  be  promoted  ))y  tlie  new  method,  and  in  a  sliort  time  the 
success  of  the  anatomical  injection  |)rovided  an  ample  compensa- 
tion for  the  failure  of  tlu^  physiological. 

Before  1650  there  exist  only  a  few  references  to  injection 
experiments  in  the  literature  of  Biology.  TIh;  idea  was  in  the 
background,  but  its  exploitation  was  delayed.  In  this  early  work 
we  should  expect  the  seeker  to  precede  the  syringe,  and  thus  we 
find  Aretaeus  the  Cappadocian,^  who  lived  in  the  second  or  third 
century  of  the  Christian  era,  demonstrating  that  '  one  may  pass 
a  plate  of  metal  from  the  vena  cava  connected  with  the  hea.rt  to 
that  by  the  spine,  and  from  the  spine  through  the  liver  to  the 
heart ;  for  it  is  the  same  passage  leading  upwards  '.  Galen  '^  goes 
a  step  further,  and  studied  the  distribution  of  the  cerebral  vessels 
by  inflating  them  with  air  through  a  tube.  Thus  the  blood 
channels  were  distended,  and  acquired  the  relief  necessary  to 
enable  them  to  be  followed  the  more  easily.  According  to  Michele 
Medici,  Alessandra  Giliani  of  Persiceto,  who  died  in  1326,  filled 
the  blood-vessels  with  liquids  of  different  colours,  which  thickened 
and  hardened  as  soon  as  they  were  injected,  but  did  not  de- 
compose. This  statement,  however,  lacks  confirmation.  The 
first  reference  to  injections  after  the  invention  of  printing  occurs 
in  the  commentary  of  Jacobus  Berengarius  published  in  1521.^ 
He  employed  a  syringe  and  injected  the  renal  veins  with  warm 
water — '  per  syringam,  aqua  calida  plenam  '.  Massa  (1536)  ^  in- 
flated the  kidney  by  forcing  air  into  the  renal  vein,  and  Stephanas 

1  Aretaeus  Cappadox,  De  causis  et  signis  acutorum  el  diuturnorum  morborum, 
Venice,  1552,  4to.  The  extant  works  of  Aretaeus  the  Cappadocian,  F.  Adams, 
London,  1856,  p.  280,  8vo. 

2  Claudius  Galenus  (c.  130-200),  De  Anatomicis  Administrationibus,  lib.  ix, 
cap.  2.    Ed.  C.  G.  Kiihn,  Leipzig,  1821-33,  8vo. 

3  Giacomo  Berengario  da  Carpi  (1470-1530),  Commentaria  cum  amplissimis 
additionibus  super  anatomiam  Mundini,  Bologna,  1521,  4to. 

4  Xieolaus  Massa  (ob.  1569),  Anatomiae  Liber  Introductorius,  seu  dissectionis 
corporis  humani,  Venice,  1536,  4to. 


THE  HISTORY  OF  ANATOMICAL  INJECTIONS      289 

(1545)  ^  devised  a  pump  to  inflate  the  vessels  with  air — ^thus  making 
their  distribution  more  conspicuous  to  the  unaided  eye.  Sylvius," 
in  his  last  work  published  shortly  after  his  death,  '  the  work  of 
his  old  age  ',  states  that  the  blood-vessels  are  better  seen  if  they 
are  inflated  with  air,  or  when  a  coloured  liquid  is  introduced  into 
them  by  means  of  little  tubes.  He  used  variously  coloured  fluids 
such  as  saffron  and  wines,  but  rejects  the  injection  method  because 
the  liquid  escapes  when  the  vessels  are  cut  and  the  preparation 
is  thereby  spoilt.  In  1556  the  Portuguese  physician  Amatus 
Lusitanus  ^  filled  the  vessels  with  a  liquid  by  means  of  a  siphon, 
or  forced  it  in  through  a  tube  by  air  pressure  supplied  from  the 
mouth. 

Eustachius  *  is  undoubtedly  one  of  the  pioneers  of  the  modern 
injection  method,  and  is  credited  by  later  authors,  such  as  Portal 
and  Milne-Edwards,  with  having  practised  more  elaborate  injec- 
tions than  his  writings  justify.  In  his  work  on  the  structure  of 
the  kidney  he  describes  the  following  procedure.  The  kidney  was 
kept  warm  by  applying  to  it  a  sponge  soaked  in  hot  water.  Tubes 
were  inserted  into  the  renal  artery  and  vein,  and  spirit  or  water 
was  injected  into  the  vessels  by  the  force  of  the  breath.  The 
fluids  entered  the  kidney,  extended  through  its  substance,  and 
passed  ultimately  into  the  pelvis  and  ureter.  In  the  converse 
experiment  of  injecting  the  ureter  it  was  found  that  the  injection 
passed  into  the  tissue  of  the  kidney  and  reached  the  arteries  and 
veins.  Again,  the  renal  artery  was  inflated,  and  air  found  its 
waj^  into  the  ureter.  The  erroneous  belief  in  a  direct  connexion 
between  the  arteries  and  the  uriniferous  tubules,  based  as  it  was 
on  injection  experiments,  survived  for  a  long  time,  and  was  taught 
in  the  anatomical  schools  throughout  the  eighteenth  century.  It 
was  not  until  Bowman  published  his  work  on  the  kidney  in  1842 
that  the  correct  relation  of  the  renal  arteries  and  veins  to  the 
glandular  tubules  was  first  completely  demonstrated.  Eustachius 
also  followed  the  course  of  the  vessels  by  the  tedious  process  of 

1  Charles  Estienne  (1504-64),  De  dissectione  partiuvi  corporis  humani,  Paris, 
1545,  fol. 

2  Jacques  Dubois  (1478-1555),  In  Hippocratis  et  GaUni  jihysiologiae  partem 
anatomicam  isagoge,  Paris,  1555,  fol. 

3  Johannes  Rodriguez  da  Castello  Bianco  (1511-68),  Curationum  Medicinalium 
Centuriae  7,  Basic,  1556,  Cent.  4  fol. 

■*  Bartolommeo    Eustacchi    (1520-74),   De   Renum    Sfrudura.    Venice.    1563, 
4to  ;   Tabidae  Anatomicae.  Rome,  1714,  fol.    Text  bv  J.  INI.  Lancisi. 


290       THK   mSTOin    OK  AXA'I^OM  K    \  I.   IN.IKCTIOXS 

oxcarnalioM,  in  wliicli,  iinlilo-  latci'  aiiittoniisis,  lie  docs  not  appear 
to  have  used  any  iiij('cti(ni.  l»o('iliaa\ c  is  of  opinion  that  Kiista- 
cliius  must  lia\c  known  of  a  more  pcitVcl  iiictliod  of  investigation 
than  inllatioii  with  air,  heeaiise  of  the  j^reat  exactness  with  wliieli 
he  trai-ed  the  vessels,  and  von  Haller  considers  tliat  plates  13  and 
27  of  the  Tdbulac,  pnhlislied  long  after  the  death  of  Kustachius, 
represent  the  vessels  so  skilfully  that  it  is  hardly  cr(;dible  they 
could  have  l)een  |)re|)are(l  without  the  assistance  of  Huid  injeetioiiH, 
unless,  as  Boerhaave  adds,  Kustachius  brought  to  bear  upon  the 
study  of  anatomy  an  "  aj)plication  and  exactness  more  than 
human'.  In  recommending  the  injection  of  liquids  he  was  cer- 
tainly in  advance  of  a  time  which  favoured  the  distension  of  the 
vessels  with  air  rather  than  filling  them  with  a  more  solid  medium. 
Thus  Laurentius,  in  1593,^  ascertained  that  there  was  a  connexion 
between  the  umbilical  vein  and  the  portal  vein  and  inferior  vena 
cava  of  the  foetus  by  inflating  the  first  named  with  a  '  hollow 
bugle  ',  and  Crooke,  in  1615,"  refers  to  the  necessity  of  having 
'  reeds,  quils,  glasse-trunkes  or  hollow  bugles  to  blow  up  the 
parts  '. 

At  about  this  time  the  possibility  of  diverting  blood  from  the 
vessels  of  one  living  animal  into  those  of  another  was  first  con- 
ceived and  practised.  The  earliest  writer  to  mention  transfusion 
experiments  was  Magnus  Pegel  in  1604,  and  others  are  Andreas 
Libavius  (1546-1616)  in  1615  and  Johannes  CoUe  (ob.  1631)  in 
1628.  It  is  to  be  noted  that  these  works  were  published  before 
Harvey's  treatise  on  the  circulation  of  the  blood. 

It  is  appropriate  that  the  most  important  of  the  early  injection 
experiments  should  have  been  made  by  Harvey  himself — '  that 
ocular  philosopher  and  singular  discloser  of  truth  '.  His  treatise 
on  the  circulation,  however,  is  silent  on  the  matter  of  injections. 
In  a  letter  addressed  to  Paul  Marquard  Slegel,  dated  March  26, 
1651,  and  published  later  by  Sir  George  Ent,'^  he  returns  to  the 
criticisms  of  Riolan  on  the  doctrine  of  the  circulation,  and  adds 
the  following  remarkable  piece  of  evidence  : 

'  It  may  be  well  here  to  relate  an  experiment  which  I  lately 
tried  in  the  presence  of  several  of  my  colleagues  and  from  the 

1  Andre  du  Laurens  (1558-1609),  Historia  Anatomica  Humani  Corporis, 
Leyden,  1593,  8vo. 

2  Helkiah  Crooke  (1576-1635),  21  icrocosmographia,  London,  1615,  fol. 

3  Sir  George  Ent  (1604-89),  Ojiera  omnia  Medico- Physica,  Leyden,  1687,  8vo. 


THE  HISTORY  OF  ANATOMICAL  INJECTIONS     291 

cogency  of  which  there  is  no  means  of  escape.  .  .  .  Having  tied 
the  pulmonary  artery,  the  pulmonary  veins  and  the  aorta,  in  the 
body  of  a  man  who  had  been  hanged,  and  then  opened  the  left 
ventricle  of  the  heart,  we  passed  a  tube  through  the  vena  cava 
into  the  right  ventricle  of  the  heart,  and  having,  at  the  same 
time,  attached  an  ox's  bladder  to  the  tube,  in  the  same  way  as 
a  clyster-bag  is  usually  made,  we  filled  it  nearl}^  fidl  of  Avarm 
water,  and  forcibly  injected  the  fluid  into  the  heart,  so  that  the 
greater  part  of  a  pound  of  water  was  thrown  into  the  right  auricle 
and  ventricle.  The  result  was,  that  the  right  ventricle  and  auricle 
were  enormously  distended,  but  not  a  drop  of  water  or  of  blood 
made  its  escape  through  the  orifice  in  the  left  ventricle.  The 
ligatures  having  been  undone,  the  same  tube  was  passed  into 
the  pulmonary  artery,  and  a  tight  ligature  having  been  put  round 
it  to  prevent  any  reflux  into  the  right  ventricle,  the  water  in  the 
bladder  was  now  pushed  towards  the  lungs,  upon  which  a  torrent 
of  the  fluid  mixed  with  a  quantity  of  blood,  immediately  gushed 
forth  from  the  perforation  in  the  left  ventricle  ;  so  that  a  quantity 
of  water,  equal  to  that  which  was  pressed  from  the  bladder  into 
the  lungs  at  each  effort,  instantly  escaped  by  the  perforation 
mentioned.  You  may  try  this  experiment  as  often  as  you  please  ; 
the  result  j^ou  will  still  find  to  be  as  I  have  stated  it.' 

Priority  of  publication,  however,  for  this  experiment  belongs 
to  others.  Marchettis,  for  example,  who  supported  Harvey  as 
against  Riolan,  in  the  presence  of  Thomas  Bartholin  in  1652, 
demonstrated  tliat  liquid  injected  into  the  arteries  emerged  by 
the  veins.  ^ 

Passing  over  Riolan,-  who  practised  inflation  of  the  vessels  for 
demonstration  purposes,  and  Lyser,'^  who  published  the  first 
general  treatise  on  anatomical  methods,  fn  which  a  blowpipe  is 
mentioned  for  inflating  with  air  or  filling  cavities  with  Avater,  but 
in  which  injections  are  not  considered,  the  next  contribution  to 
the  subject  is  by  Glisson.'*  He  injects  with  a  tube  to  which 
a  bladder  containing  the  medium  is  attached.  The  tube  is  pushed 
into  the  vessel  and  tied,  the  bladder  filled  with  the  injection  and 
bound  to  the  tube,  and  the  fluid  forced  into  the  vessels  by  com- 
pressing the  bladder  at  first  gently  and  then  more  firmly.     The 

^  Domenico  de  Marchettis  (1626-88),  Anatomia,  cut  responsiones  ad  Riolanum 
■  ■  ■  additae  sunt,  Padua,  1652,  4to. 

2  Jean  Riolan,  fil.  (1577-1657),  Opuscula  anatomica  varia  et  nova,  Paris, 
1652,  12mo. 

3  Michael  Lyser  (1627-60),  Culler  Anatomicus,  Copenhagen,  1653,  8vo. 
*  Francis  Glisson  (1597-1677),  Anatomia  Hepatis,  London,  1654,  8vo. 


2!»i>      ^I'MK   HISTOIIN    OK  AXATO.MK   \L   IXJKCTfOXS 

lueclia  ciuijloycd  arc  hot  water  hy  itself  or  mixed  witli  milk,  water 
coloured  with  salTioii,  and  ink.  A  figure  is  given  of  iiis  {i|)|)aratus, 
l>ut  it  is  of  little  assistance  in  following  the  description. 

We  now  come  to  '  that  miracle  of  a  youth—  Christopiier  Wren  ', 
whose  ex[)eriments  iiave  been  described  l)y  Boyle  '  and  Oidenherg.- 
Accordiiig  to  the  Philosophical  Transactions  of  1665,  Wren  (1632- 
1723)  first  suggested  to  Boyle  at  Oxford  not  later  than  1659  ''  to 
ligature  the  veins  of  a  living  animal,  open  them  on  the  side  of 
the  ligature  nearest  the  heart,  and  inject  with  '  slender  syringes 
or  quills  fastened  to  bladders  '.  He  recommended  as  the  subject 
'  pretty  big  and  lean  dogs  '.  This  o])eration  a[)pears  to  have  been 
frequently  practised  in  Oxford,  and  also  in  London  before  the 
Royal  Society.  '  And  they  hope  likewise,  that  beside  the  medical 
uses,  that  may  be  made  of  this  invention,  it  may  also  serve  for 
anatomical  purposes,  by  filling,  after  this  way,  the  vessels  of  an 
animal  as  full,  as  they  can  hold,  and  by  exceedingly  distending 
them,  discover  new  vessels.'  '  To  Oxford,  and  in  it,  to  Dr.  Christo- 
pher Wren,  this  invention  is  due.'  Wren,  then  a  youth  of  twenty- 
four,  injected  wine  and  ale  into  the  blood  of  a  living  dog  by  one 
of  the  veins,  and  noted  that  the  animal  became  extremely  drunk. 
The  experiment  he  takes  '  to  be  of  great  concernment  and  what 
will  give  great  light  to  the  theory  and  practice  of  physic  ',  and 
Sprat  refers  to  it  as  that  '  noble  anatomical  experiment  of  injecting 
liquors  into  the  veins  of  animals  '.  We  may  now  complete  what 
remains  to  be  said  on  the  history  of  physiological  injections,  which 
we  have  already  seen  were  known  to  Pegel  and  Libavius  long 
before  Wren's  first  experiment  in  1656.  According  to  J.  M. 
\'erdries,  a  large  ox  at  once  died  when  Wepfer  injected  air  into 
its  jugular  vein,  and  Major  *  asserts  that  transfusion  experiments 
on  dogs  were  practised  by  Hans  Jurge  de  Wahrensdorf  in  1642. 
Elsholz  ^  injected  medicines  into  the  veins  of  man  and  dogs,  and 

1  Hon.  Robert  Boyle  (1627-91),  Of  the  Usefulnesse  of  Xaturall  Philosophy, 
Oxford,  1663,  4to,  pp.  62-5. 

2  Henry  Oldenberg  (1615-77),  '  Account  of  the  Rise  and  Attempts  of  a  w'a\' 
to  convey  liquors  immediately  into  the  mass  of  blood,'  Philosophical  Transactions, 
London.  1665.  4to,  vol.  i.  p.  128. 

3  An  error.    Wren's  first  experiment  was  undertaken  in  1656. 
*  Johann  Daniel  Major  (1634-93),  Prodromus  inventae  a  se  Chirurgiae  infu 

soriae.  Leipzig.  1664,  8vo. 

5  Johann  Siegesmund  Elsholz  (1623-88),  Clysmatica  Nova,  Berlin,  1665, 
12mo. 


1 


Plate  XLII.     R  E  I  N  I  K  R    D  E   G  R  A  A  F 


-^4 


t-*^  t^ 


From  the  first  edition  of  the  Dc  Vsu  Siplionis  (1668). 
Signature  from  a  MS.  in  the  possession  of  the  Royal 
Society  (Photograph  supphed  b}-  Dr.  Charles  Singer). 


THE  HISTORY  OF  ANATOMICAL  INJECTIONS      293 

also  practised  transfusion  of  the  blood.  Lower  (1666)  ^  was  the 
first  to  undertake  transfusion  of  blood  from  an  artery  of  one 
animal  into  the  vein  of  another,  and  in  the  following  year  Jean 
Denys  performed  the  same  operation  on  man — '  a  circumstance 
of  great  exultation  to  the  French  '.  Boerhaave,  in  commenting 
on  this  result,  says  :  '  the  experiment  was  soon  received  with 
great  applause  both  through  France  and  England,  and  great  things 
were  expected  from  it  in  the  cure  of  diseases  and  the  recovery  of 
youth  .  .  .  but  in  a  little  time  all  these  expectations  disappeared, 
and  the  experiment  was  prohibited  to  be  made  on  men  by  the 
public  law  '.  In  a  letter  to  N.  Steno,  dated  1667,  but  not  published 
at  the  time,  Francesco  Redi  (1626-98)  mentions  that  he  had 
instantly  killed  two  dogs  and  a  hare  by  injecting  air  into  the 
veins,  but  a  sheep  and  two  foxes  died  more  slowly.  Finally 
Clarke  (1668)  ^  states  that  he  had  been  engaged  for  many  years 
in  injecting  various  liquids  into  the  blood  of  living  animals,  but 
he  had  grave  doubts  as  to  its  utility  except  for  anatomical  pur- 
poses. The  minutes  of  the  Royal  Society  for  May  28,  1660,  record 
that  '  Dr.  Clarke  was  intreated  to  bring  in  the  experiment  of 
injections  into  the  veins  ' — which  doubtless  refers  to  the  physio- 
logical experiment. 

From  Glisson  up  to  the  time  of  de  Graaf  sufficient  progress 
was  made  in  the  methods  of  injection  to  justify  the  statement 
that  de  Graaf  simply  collated  and  fixed  the  knowledge  of  his 
time,  but  added  to  it  little  that  was  new.  Wepfer  ^  investigated 
the  vascular  supply  of  the  brain  by  means  of  injections  of  saffron 
water,  and  gives  the  first  correct  description  of  the  course  and 
branching  of  the  carotid  artery  and  of  the  vessels  of  the  brain 
membranes.  Important  results  were  acliieved  by  Malpighi.*  He 
recommends  examining  the  vessels  of  the  lungs  under  the  powerful 
illumination  of  the  rays  of  the  sun.    If  this  should  prove  inadequate 

1  Richard  Lower  (1631-91),  '  The  success  of  the  experiment  of  transfusing  the 
blood  of  one  animal  into  another',  Philosophical  Transactions,  London,  1666, 
4to,  vol.  i,  p.  352. 

2  Timothy  Clarke  (ob.  1672),  '  Some  anatomical  inventions  and  observations, 
particularly  relative  to  the  origin  of  the  injection  into  veins,  tlie  transfusion  of 
blood,  and  the  parts  of  generation'.  Philosophical  Transactions,  London,  1668, 
4to,  vol.  iii,  p.  672. 

3  Johann  Jakob  Wepfer  (1620-95),  Observationes  Anatomicae,  Schaffhausen, 
1658,  Svo. 

4  Marcello  Malpighi  (1628-94),  De  Pulmonibus,  Bologna,  1661,  fol. 

2391  TT 


•294      THK   HISTORY  OK  ANATOMICAL  IN.IK(TTONS 

air  may  Ix-  diixcn  into  the  luaiii  trunk  of  the  |)ulm()nary  artery, 
wlicii  (Ih-  ncsscIs  will  s\\<'ll  up  aiul  appear  in  all  llicir  ramifications 
as  if  they  were  carved  witli  a  (tinsel.     I^A'en  the  Hnialie.st  })ranche.s 
are  dilated  and  stretched  out  like  the  })ranches  of  a  tree.     Or  if 
a  still  ?nore  refined  method  be  necessary,  mercuiry  can  V)e  syringed 
into  the  same  vessel,  whereupon  all  its  branches  up  to  the  finest 
twigs  will  assume  a  beautiful  silver  colour.     But  the  doubt  which 
still,  he  says,  tortured  his  mind,  which  his  injection  of  liquids  of 
dill'erent  colours  did   not   resolve,   was   whether  the  arteries  and 
veins  were  discontinuous,  and  only  connected  up  indirectly  by 
a    s|)ongy    parenchyma,    or    whether    the   junction    was    effected 
directly  by  microscopic  vessels.     He  repeats  Harvey's  exjoeriment, 
and  finds  that  water  or  a  black  liquid  syringed  into  the  ])ulmonary 
artery  emerges  by  the  pulmonary  vein.    Sometimes  also  it  emerges 
by  the  trachea.     He  is  not  misled  by  this  surprising  result,  but 
realizes  that  injections  may  extravasate  and  give  rise  to  erroneous 
conclusions.    Subsequently  he  saw  the  blood  capillaries  in  the  lung 
of  the  frog,   but  injections  played  no  part  in  that  memorable 
discovery.     A  few  years  later,  in  1666,^  Malpighi  is  investigating 
the  structure  of  the  kidney  by  injection  methods.     He  used  ink, 
urine  coloured  with  ink,  a  black  or  other  coloured  liquid,  and 
a  black  liquid  mixed  with  spirits  of  wine.    A  coloured  fluid  injected 
with  a  syringe  into  the  renal  artery  reaches  the  smallest  branches 
of  the  artery  and  the  '  internal  glands  '  (since  called  Malpighian 
bodies),  so  as  to  produce  the  appearance  of  a   '  beautiful  tree 
loaded  with  apples  '.    He  was  not  able  to  inject  these  bodies  from 
the  veins,   nor  could  the  uriniferous  tubules  be  injected  either 
from  arteries  or  veins.     He  regards  the  uriniferous  tubule  as  the 
excretory  duct  of  the  Malpighian  body,  but  did  not  succeed  in 
actually  demonstrating  the  connexion  between  them. 

Bellini,  who  was  only  nineteen  years  of  age  when  he  produced 
his  remarkable  work  on  the  structure  of  the  kidnej^"  is  said  to 
have  used  an  injection  medium  which  melted  with  heat.  He 
mentions  mercury,  which  he  appears  to  have  employed  for  injec- 
tion purposes,  and  talks  of  artificially  distinguishing  the  vessels 
by  injecting  some  coloured  liquid  into  the  renal  artery  and  vein, 
but  does  not  state  the  nature  of  the  medium  or  the  colours  selected. 

1  Marcello  Malpighi.  Exerciiatio  Anatomica  de  Renibus,  Bologna,  1666,  4to. 

2  Lorenzo  Bellini  (1643-1704),  De  Struchira  Renum,  Florenctu.  1662,  4to. 


THE  HISTORY  OF  ANATOMICAL  INJECTIONS      295 

Robert  Boyle  ^  is  responsible  for  a  striking  contribution  to  the 
technique  of  injection.     He  says  : 

'  And  perhaps  there  may  be  some  way  to  keep  the  arteries 
and  the  veins  too,  when  they  are  empty'd  of  blood,  plump,  and 
unapt  to  shrink  overmuch,  by  filling  them  betimes  with  some 
such  substance,  as,  though  fluid  enough  when  it  is  injected  to  run 
into  the  branches  of  the  vessels,  will  afterwards  quickly  grow  hard. 
Such  may  be  the  liquid  plaister  of  burnt  Alabaster,  formerly 
mention'd,  or  ising-glass  steeped  two  days  in  water,  and  then 
boild  up,  till  a  drop  of  it  in  the  cold  will  readily  turn  into  a  still 
gelly.  Or  else  Saccarum  Saturni,  which,  if  it  be  dissolv'd  often 
enough  in  spirit  of  vinegar,  and  the  liquor  be  each  time  drawn 
off  again,  we  have  observ'd  to  be  apt  to  melt  with  the  least  heat, 
and  afterwards  to  grow  quickly  into  a  somewhat  brittle  consistence 
again.' 

This  is  the  first  unequivocal  mention  of  solidifying  injection 
media,  and  it  is  noteworthy  that  two  of  them,  plaster  and  gelatin, 
are  in  use  at  the  present  day,  and  also  that  Boyle  does  not  suggest 
the  addition  of  colour — an  improvement  with  which  he  can  hardly 
have  been  unfamiliar.  Whether  he  ever  carried  his  suggestions 
into  practice  is  doubtful.  It  is  true  that  Grew  in  1681  asserts 
that  Boyle  was  the  first  to  use  wax  as  an  injection  mass,  but 
Boyle  himself  says,  '  but  I  must  not  insist  on  these  fancies ' ;  and 
again  in  1659,  when  commenting  on  the  anatomical  methods  of 
de  Bills,  '  most  of  the  ways  I  proposed  to  myself  were  as  yet  httle 
more  than  bare  designs  '.  Saccarum  Saturni,  it  may  be  mentioned, 
is  acetate  or  sugar  of  lead,  the  preparation  of  which  by  the  old 
method  is  given  by  James. ^    It  has  a  waxy  consistency. 

In  his  work  on  the  anatomy  of  the  brain,  Wilhs  ^  brings  the 
new  method  into  useful  practice.  The  vessels  of  the  brain,  he 
says,  are  '  seen  better  and  more  distinctly,  if  you  first  squirt  into 
the  carotidick  artery  some  black  liquor  '.  He  injects  the  rete 
mirabile  of  ruminants  from  the  carotid  with  ink,  and  finds  that 
the  injection  reaches  the  carotid  of  the  other  side.  In  another 
passage  his  instruments  are  mentioned,  as  follows  : 

'  Let  the  carotidick  arteries  be  laid  bare  on  either  side  of  the 
cervix  or  the  hinder  part  of  the  head,  so  that  their  little  tubes  or 

1  Hon.  Robert  Boyle  (1627-91),  Of  the  Usefulnesse  of  Naturall  Philosophy, 
Oxford,  1663,  4to. 

2  Robert  James  (1705-76),  A  Medicinal  Dictionary,  London,  1745,  fol., 
vol.  iii,  art.  Plumbum. 

8  Thomas  Willis  (1621-75),  Cerebri  Anatome,  London,  1664,  4to. 

U  2 


L>9()     TllK  HISTORY  OF  ANATOMICAL  INJECTIONS 

pipes,  about  hall  an  inch  l()n<(,  may  bo  cxhibitc^d  together  to  the 
sight ;  tlien  let  a  dyed  liquor,  and  contained  in  a  large  squirt  or 
pij)e,  be  injected  upwards  iii  the  trunk  of  one  .side,  aft(T  once 
or  twice  injecting,  you  shall  see  the  tincture  or  dyed  liquor  to 
descend  from  the  otlier  side  by  the  trunk  of  the  opposite  artery  ; 
yea,  if  the  same  be  more  copiously  injected  towards  tlie  head, 
from  thence  returning  through  the  artery  of  the  opiujsite  side,  it 
w^ll  go  thorow  below  the  Praecordia,  even  to  the  lower  region  of 
the  body  ;  when  in  the  meantime,  little  or  nothing  of  the  same 
tincture  is  carried  thorow  the  outward  and  greater  jugular  veins. 
Then  the  head  being  opened,  all  the  arteries,  before  the  entrance 
of  the  head,  and  the  veins  of  the  same  band  with  them,  will  be 
imbued  with  the  colour  of  the  same  injected  liquor.' 

Some  years  later,  in  1672,^  Willis  was  the  first  to  inject  an 
Invertebrate.  In  an  involved  passage  describing  the  heart  and 
gills  of  the  lobster,  he  mentions  injecting  a  '  black  liquor '  into 
the  heart,  from  which  it  passed  to  the  gills  (!).  He  also  injected 
the  same  liquid  into  the  afferent  branchial  artery  of  a  fish,  and 
noted  that  it  circulated  through  the  gill  and  finally  reached  the 
dorsal  aorta.  Notwithstanding  this  significant  result  his  ideas  on 
the  circulation  of  the  blood  in  fishes  are  confused  and  difficult 
to  follow.  In  1675  ^  Willis  investigates  the  structure  of  the  lungs 
by  means  of  injections  of  the  arteries,  veins,  and  bronchi.  He 
notes  how  these  three  factors  are  associated  in  the  lung  tissue, 
and  points  out  how  impossible  it  is  to  grasp  their  relations,  or 
make  a  representation  of  them,  without  injections.  He  recom- 
mends '  quicksilver,  hot  and  flowing  gypsum,  wax  mingled  and 
made  liquid  with  oyl  of  turpentine,  or  some  such  matter '.  No 
colours  are  mentioned,  which  is  again  extraordinary,  seeing  that 
he  was  writing  after  Swammerdam,  with  whose  work  he  must 
have  been  acquainted. 

On  March  27,  1667,  Pecquet  ^  described  a  supposed  connexion 
between  the  thoracic  duct,  which  he  had  rediscovered  in  1651, 
and  the  renal  vein  in  Man  by  inflating  the  duct  with  air  through 
a  quill.     In  this  w^ork  he  was  assisted  by  Louis  Gayant,  one  of 

1  T.  Willis,  De  Anima  Brutorum,  London,  1672,  8vo.  Also  editions  at  Oxford 
and  Amsterdam  bearing  same  date. 

2  T.  Willis,  Pharmaceutice  Rationalis,  2,  Oxford,  1675,  4to. 

3  Jean  Pecquet  (1622-74),  '  A  new  Discovery  of  the  communication  of  the 
ductus  thoracicus  with  the  emulgent  vein ',  Philosophical  Transactions,  London, 
1667,  4to,  vol.  ii,  p.  461.  Translation  of  a  letter  which  appeared  in  the  Journal 
des  Sgavans,  1667,  8vo.,  and  elsewhere. 


THE  HISTORY  OF  ANATOMICAL  INJECTIONS      297 

the  Parisian  comparative  anatomists.  On  February  8,  1672, 
Pecquet  ^  professes  to  have  discovered  by  injections  a  direct  con- 
nexion between  the  thoracic  duct  and  the  postcaval  vein.  He 
forced  into  the  thoracic  duct  with  a  syringe  hot  milk  or  a  substance 
which  was  fluid  when  thrown  in  hot  but  solidified  on  cooling.  He 
gives  no  indication  as  to  what  this  substance  was,  but  states  that 
the  method  succeeded  '  in  part '.  Before  the  operation,  the  body 
was  warmed  by  injecting  nearly  boiling  milk.  As  regards  publica- 
tion, Pecquet  slightly  anticipates  Swammerdam's  '  invention '  of 
a  solidifying  injection  medium,  and  was  himself  anticipated  by 
Boyle.  Walter  Needham,  who  criticizes  Pecquet's  paper  in  the 
Philosophical  Transactions  for  1672,  and  points  out  his  mistakes, 
refers  to  the  '  coagulating  injection  ',  but  does  not  appear  to  have 
been  greatly  impressed  by  it. 

A  year  before  the  publication  of  de  Graaf's  tract,  '  Theodorus 
Aides  '  ^  injected  the  arteries  of  a  foetal  cow  with  a  black  hquid, 
and  found  correctly  that  the  uterine  cotyledons  were  uninjected. 
The  reverse  experiment  of  injecting  the  uterine  arteries  was 
responsible  for  the  erroneous  belief  that  the  placentae  could  be 
injected  from  the  cotyledons.  Monro,  however,  considers  that  in 
the  latter  case  Slade's  expression  '  "  carried  into  the  substance  of 
the  placentae  "  may  signify  no  more  than  effused  on  their  unequal 
pappy  substance  '. 

The  small  tract  by  de  Graaf,  published  in  1668,^  is  important 
not  as  an  original  contribution  to  the  subject,  but  because  it 
brings  contemporary  knowledge  to  a  focus,  and  determines  the 
fate  of  the  injection  method.  He  is  the  first  to  figure  an  injecting 
syringe  of  the  modern  pattern,  and  is  credited  with  having 
injected  mercury  into  the  spermatic  vessels.  He  says  his  atten- 
tion had  been  directed  to  the  subject  of  injections  five  years 
previously,  owing  to  the  great  difficulty  of  tracing  the  blood- 
vessels by  the  methods  of  dissection  then  in  use.  By  means  of 
his  syringe,  however,  it  was  possible  to  demonstrate  all  the  arteries 
and  veins  of  the  body  in  a  single  day.     Again,  it  was  possible 

1  J.  Pecquet,  '  Une  nouvelle  decouverte  de  la  communication  du  canal  thora- 
chique  avec  la  veine  cave  inferieure',  Journal  des  Sgavans,  Paris,  1672,  8vo. 

2  Matthaeus  Slade  (1628-89),  Dissertatio  epistolica  contra  Qui.  Harveum 
interpolata,  Amsterdam,  1667,  8vo. 

3  Reinier  de  Graaf  (1641-73),  De  Usu  Siphonis  in  Anatomia,  Leyden  and 
Rotterdam,  1668,  8vo. 


29S      THE  HISTORY  OF  ANATOMK^AL  INJECTIONS 

to  establish  by  experiment  the  circulation  of  the  blood.  A  liquid 
injected  into  the  carotid  artery,  after  circulating  through  the 
brain,   returned   by   the   jugular   vein,   and    if   injected   into  the 


Fig.  1.    Engraved  title  of  the  first  edition  of  the  De  Usu  Siphonis  (1668). 

pulmonary  artery  it  returned  by  the  pulmonary  vein  to  the  left 
side  of  the  heart.  Other  experiments  of  a  similar  nature  are 
described.  Thus  de  Graaf,  as  well  as  Malpighi  and  others,  anti- 
cipates the  pubUcation  of  Harvey's  pioneer  experiment  made  in 
1651.     De  Graaf  describes  the  injection  Uquids  used.     They  are 


THE  HISTORY  OF  ANATOMICAL  INJECTIONS      299 


all  watery  preparations  and  have  no  permanency.  A  beautiful 
dark  blue  colour,  he  says,  may  be  obtained  by  the  action  of  sal 
ammoniac  on  copper.  If  this  is  found  too  difficult  to  prepare, 
use  may  be  made  of  colours  extracted  from  flowers,  such  as  the 
violet,  cornflower,  and  rose.  All  these  colours  may  be  changed 
by  appropriate  reagents,  so  that  if  only  one  extract  is  to  hand 
other  colours  may  be  prepared 
from  it.  Further  colours  avail- 
able are  gamboge  and  indigo, 
and  a  green  is  obtainable  by 
mixing  the  two.  He  recom- 
mends gamboge  and  indigo  be- 
cause they  are  easily  procured, 
and,  unlike  sal  ammoniac,  do 
not  affect  the  metal  of  the 
syringe. 

A  typical  and  important 
experiment  is  thus  described 
by  de  Graaf.  If  the  carotid 
artery  is  injected  towards  the 
liead  with  the  green  medium 
one  sees 

'  omnes  partes,  tam  internas, 
quam  externas,  quae  ab  arte- 
riis  carotidibus  sanguinem  acci- 
piunt,  colore  viridi  tingi ;  quod 
iucundissimum  spectaculum  in 
cerebro  exhibet,  cuius  super- 
ficies tam  dextra  quam  sinistra, 
propter  anastomosin,  quam  in- 
terse  habent  utriusque  lateris 
arteriae  ab  iniecto  colore  viridi 
plurimas  quasi  arborum  figuras  repraesentare  videntur,  quae  non 
sunt  nisi  arteriarum  ramificationes  per  cerebrum  excurrentes  '. 

Another  example  of  de  Graaf  s  ingenuity  is  to  inject  the  coeliac 
artery  with  a  green  medium,  and  the  mesenteric  artery  with 
a  yellow.  He  was  thus  able  to  delimit  in  a  very  diagrammatic 
way  the  portions  of  the  gut  supplied  respectively  by  these  two 
vessels.  Milk  injected  into  the  liver  gives  it  a  white  colour,  and 
similarly  the  gland  becomes  green  if  a  green  liquid  is  used,  from 
which  he  concludes  that  the  colour  of  the  liver  is  dependent  on 


Fig.  2.    Dc  Graaf's  injection  syringe  and 
accessories  (1668) 


:m)      THE  HIS'I'OIIN'  OF  ANATOMICAL  IN.)K(  TIONS 

tlu'  cuutciiis  ot  its  vessels.  Tlic  tlioiacic  duct  is  injected  and 
distended  with  inill<,  and  the  uterine  vessels  are  inflated  with  air 
(1672).  He  also  investigates  the  connexion  between  the  vas 
deferens,  seniinai  xcsieles,  and  urethra  by  iiije(;tions,  and  in  the 
same  way  shows  that  the  penis  can  be  erected  after  death  })y 
injecting  the  internal  iliac  artery.  His  injection  experiments  were 
largely  responsible  for  the  debateablc  view,  held  until  comparatively 
recently,  that  the  Mammalian  seminal  vesicle  acts  as  a  receptacle 
for  the  s[)ermatozoa. 

De  Oraaf's  syringe  is  not  dissimilar  to  the  modern  instrument. 
It  is  made  of  coi)per  or  silver.  The  canula  is  long  and  bent,  and 
is  screwed  directly  to  the  syringe,  being  tightened  with  a  key  and 
the  joint  made  good  by  a  leather  washer.  There  is  no  stopcock. 
The  piston  is  packed  with  thread,  and  the  key  is  drilled  out  to 
contain  brass  wires  for  cleaning  the  canula.  Straus-Durckheim 
in  1843  states  that  the  injection  syringe  had  hardly  been  modified 
since  the  time  of  de  Graaf,  and  that  Swammerdam's  methods 
were  still  in  use. 

In  a  paper  dated  December  17,  1668,  King  ^  describes  the 
structure  of  the  testis.  He  holds  that,  apart  from  the  arteries 
and  veins,  the  testis  consists  of  massed  tubules — '  is  a  mere  scheme 
or  congeries  of  vessels  '.  He  proves,  that  they  are  hollow  by 
injecting  them  with  coloured  spirit.  These  tubules,  according  to 
King,  can  be  demonstrated  in  the  rat  by  dissecting  off  the  tunica 
albuginea  and  shaking  them  out  in  water,  as  first  shown  by  de 
Graaf. 

The  Parisian  comparative  anatomists  of  the  seventeenth 
century-  made  little  use  of  injection  methods,  but  the  few  experi- 
ments they  describe  deserve  attention.  They  study  the  structure 
of  the  kidney  of  man  and  the  lion  by  injecting  milk  into  the  renal 
vein,  and  are  thus  able  to  dispose  of  the  statement  of  Vesalius 
that  the  factors  of  the  renal  vein  arise  in  the  centre  of  the  kidney. 
If  an  injection  be  thrown  into  the  pulmonary  artery  of  a  dog,  it 
traverses  the  lung  and  emerges  by  the  pulmonary  vein  much  more 
easily  and  quickly  if  the  lung  be  kept  inflated  by  a  pair  of  bellows. 
In  the  tortoise  they  investigate  the  relations  of  the  epididymis 

1  Sir  Edmund  King  (1629-1709),  '  Observations  concerning  the  organs  of 
generation  ',  Philosophical  Transactions,  London,  1669,  4to,  vol.  iv,  p.  1043. 

2  Claude  Perrault  (1613-88),  Memoires  pour  servir  d  Vkistoire  naturelle  des 
animaux,  Paris,  1671,  1676,  fol. 


THE  HISTORY  OF  ANATOMICAL  INJECTIONS      301 

and  testis,  and  conclude  that  the  former  is  simply  a  convoluted 
tube.  '  Having  made  an  injection  of  a  coloured  liquor  into  this 
ductus,  a  great  many  other  httle  ductus's  were  made  to  rise, 
which  did  not  appear  before,  and  which  went  from  the  testicle 
to  the  epididymis  :  these  ductus's  being  enclosed  in  the  membrane 
which  retained  the  circumvolutions  of  the  epididymis,  and  which 
fastened  it  to  the  testicle.'  This  result,  combined  with  that 
described  by  King  in  1668,  may  be  said  to  inaugurate  our  modern 
knowledge  of  the  structure  of  the  testis  and  its  related  ducts,  but 
it  was  not  until  1745  that  Haller  put  the  whole  matter  in  a  con- 
vincing light. 

Swammerdam  ^  is  usually  regarded  as  the  inventor  of  the 
solidifying  injection  mass.  We  have  already  seen  that  this  claim 
cannot  strictly  be  maintained,  but  it  is  also  undeniable  that  Swam- 
merdam stereotyped  the  method,  and  was  responsible  for  its 
general  adoption  by  anatomists  after  his  time.  Priority  of  publica- 
tion may  belong  to  Boyle  and  Pecquet,  but  it  is  to  Swammerdam, 
one  of  the  greatest  practical  anatomists  of  all  time,  that  the  credit 
rightly  belongs.  According  to  the  life  by  Boerhaave,  who  is 
followed  by  Straus-Durckheim,  the  first  wax  injection  was  made 
in  van  Home's  house  in  Leyden  on  January  22,  1667,  but  this 
date  is  obviously  an  error,  and  is  in  fact  contradicted  not  only 
by  another  passage  in  the  same  work,  but  also  by  Swammerdam 
himself,  who  states  that  in  1666,  1669,  and  1670  he  demonstrated 
his  method  to  van  Home,  Slade,  Thevenot,  and  Steno.  His  results 
were  to  some  extent  incorporated  in  J.  van  Home's  Prodromus 
of  1668,  but  the  facts  seem  to  be  that  whilst  van  Home  suggested 
the  wax  method,  it  was  Swammerdam  who  first  reduced  it  to 
practice.  Swammerdam  says  :  '  Factum  est,  ut  T>.  van  Home 
proponerem,  structuram  venarum  et  arteriarum  beneficio  iniectae 
rubrae  vel  virentis  cerae  detegi  posse.'  J.  Hudde  (1640-1704), 
the  eminent  Dutch  mathematician,  also  proposed  to  Swammerdam 
the  use  of  coloured  injection  media.  Boerhaave  adds  that  the 
three  plates  of  six  figures  were  sent  to  the  Royal  Society  on  May  1, 
1672,  accompanied  by  the  actual  specimen  itself.  The  body  of 
the  pubHshed  work  is  dated  March  5,  1670  [1671],  and  the  appendix 
May  1,  1672.    The  preparation  of  the  uterus  was  in  the  collection 

*  Jan    Swammerdam    (1637-80),    Miraculum    naturae,    sive    uteri    muliebris 
fabrica,  Leyden,  1672,  4to. 


:i02      'IHK  HISTORY  OF  ANATOMICAL  IN.IKCTJONS 

of  tlu'  Royal  Society  in  1()S1,  when  it  was  calalo^U(;(l  by  Grew 
in  the  following  words  :  '  Tlu;  womb  of  a  woman,  blown  up  and 
dried.  Together  with  the  .rpermatick  vessels  annexed  ;  and  the 
arteries  in  th(^  })ott()m  of  tin;  uterus^  nndnlatcnl  like  the  claspers 
of  a  vine  ;  all  filled  up  with  .soft  wax.  Also  the  membranous  and 
round  ligaments  of  the  womb,  the  ureters^  bladdery  clitoris,  nympltae, 
hymen.    Fallopian   tube,    and    the   ovarys,    commonly    called    the 


Fig.  3.     Uterus  injected  with  red  wax  by  Jan  Swammerdam  (1671),  who  presented  this 

specimen  to  the  Royal  Societj'. 

testicles  ;  all  made  most  curiously  visible,  and  given  by  Dr.  Swam- 
merdam. The  descriptions  and  figures  hereof  may  be  seen  in  the 
same  author's  book,  printed  at  Leydeji,  1672,  and  presented  to 
the  Royal  Society.^  In  1781  the  Royal  Society's  museum  was 
handed  over  to  the  British  Museum,  and  Swammerdam's  injected 
specimens  of  the  uterus,  gall  bladder,  and  spleen  have  since  been 
lost  sight  of.  Swammerdam  gives  a  brief  description  of  his  method. 
He  used  pure  white  wax,  to  which,  when  liquid,  the  red,  yellow, 
green,  or  other  colour  as  required  was  added.  The  medium  was 
injected  as  a  hot  liquid  with  a  syringe,  care  being  taken  to  avoid 
the  admission  of  air  into  the  vessels  because  this  was  found  to 


THE  HISTORY  OF  ANATOMICAL  INJECTIONS      303 


impede  the  injection.  Before  injecting,  the  blood  was  pressed  out 
of  the  larger  vessels  in  order  that  they  might  quickly  and  easily 
fill.  When  cool  the  wax  solidified  in  the  vessels,  and  the  result 
was  a  permanent  preparation  which  could  not  bleed  if  it  should 
be  necessary  to  dissect  it.  The  discovery  was  communicated  to 
his  friend  Ruysch,  who  hailed  Swammerdam  in  emphatic  language 
as  the  inventor  of  the  wax  method.  The  uterus  described  in  1672 
was  injected  with  soft  red  wax,  blown  up,  and  dried.  Swam- 
merdam also  practised  colouring  the  wax  differently  for  arteries 
and  veins,  and  had  previously  in  1667  attempted  physiological 
injections  of  acid  liquids  into 
the  veins  of  living  animals.  In 
his  history  of  bees,  first  pub- 
hshed  in  1738,^  there  is  an  inter- 
esting description  of  how  he 
injected  the  blood-vessels  of  a 
Lepidopterous  larva.  He  says 
the  blood-vessels  of  insect  larvae 
are  so  very  delicate  and  trans- 
parent that  they  cannot  ordin- 
arily be  discerned. 


Fig.  4.  Swaminerdam's  method  of  injecting  the 
small  vessels  of  insects  (first  published  1738). 


'  though  there  are  inventions  of 
art,  by  the  assistance  of  which 
we  may  come  to  the  knowledge  of  them.  In  Silkworms  I  suc- 
ceeded by  the  following  method.  ...  I  provide  myself  with  a  little 
glass  tube,  .  .  .  which  I  take  care  to  have  made  like  a  vial  in  the 
middle,  at  one  end  to  be  drawn  out  to  the  utmost  smallness,  and 
at  the  other  end  made  thicker  and  broader,  in  order  that  the  air 
blowing  into  it,  may  be  conveniently  forced  in  at  this  end  :  this 
done,  I  fill  the  little  pipe  with  some  thin  liquor  coloured,  not,  how- 
ever, of  a  very  penetrating  kind,  let  in  through  the  thicker  end, 
and  then  with  the  greatest  caution  perforating  the  skin,  I  thrust  the 
thinner  end  into  the  heart.  This  may  be  done  easily  enough.  By 
these  means,  and  then  gently  blowing  into  it,  the  heart,  and  many 
of  the  vessels  shooting  out  from  it,  may  be  filled.' 

It  is  generally  admitted  that  Frederik  Ruysch,  the  Professor 
of  Anatomy  at  Amsterdam,  is  the  apostle  of  the  injection  method,"^ 
which  was  in  fact  for  some  time  referred  to  as  the  '  Ruyschian 

^  J.  Swammerdam,  Biblia  Naturae,  Leyden,  1737-8,  fol. 

2  Frederik   Ruysch    (1638-1731),  Opera  Omnia  Ayiatomico-medico-chirurgica, 
Amsterdam,  1721-5,  4to. 


304       IHK  HISTOKV   OF  ANATOMICAL  INJECmONS 

art '.     Even  his  opponent  Bidloo  admits  that  he  was  a  '  subtle 
butcher ',  who  welcomed  oven  a  civil  war  which  was  to  provide 
him  with   material  for  his  studies.     Ruysch  was  occui)ied  with 
anatomy  ])otween  1665  and  1728,  and  from  about  1675  onwards 
was  recognized  as  the  leading  exponent  of  injection  experiments. 
He   was   the   intimate   friend   of   de   Graaf,   Swammerdam,    and 
Boerhaave.     Ruysch's  object  was  to  ])roduc(^  finer  and  more  com- 
plete  and  permanent   injections  than   his   ])r(^decessors.      In  the 
latter  respect  he  was  anticipated  by  ISwammerdam,  but  he  suc- 
ceeded in  being  the  first  to  obtain  extensive  injections  of  the 
blood   capillaries.      His   ])reparations   surprised    '  even   the   most 
learned  part  of  mankind  ',  and,  to  quote  Boerhaave,  he  was  the 
first  to  demonstrate  that  there  were  not  two  arteries  distributed 
alike  throughout  the  whole  body,  for  '  in  the  liver  they  appear 
like  small  pencil  brushes,  in  the  testicles  they  are  wound  up  like 
a  ball  of  thread,  in  the  kidneys  they  are  inflected  into  angles  and 
arches,  in  the  intestines  they  ramify  like  the  branches  of  trees, 
in  the  uvea  they  form  circles  and  radii,  in  the  brain  they  are 
waved  in  and  out  in  a  serpentine  course,  in  the  omentum  they 
are  disposed  something  like  the  meshes  of  a  net,  and  in  almost 
every  other  part  of  the  body  they  assume  a  different  and  peculiar 
structure  '.     Already  in  1664,  as  he  tells  us  himself,  Ruysch  was 
making  injected  preparations  of  the  spleen  of  the  calf  which  were 
publicly  demonstrated  with  applause  by  J.  van  Home. 

Galen  and  the  ancients  believed  that  there  were  parts  of  the 
body,  to  which  they  gave  the  name  '  spermatic  ',  which  had  no 
vascular  supply  of  any  kind.  This  belief  survived  until  the 
seventeenth  century,  when  the  fine  wax  injections  of  Ruysch 
demonstrated  the  occurrence  of  blood-vessels  in  bones,  ligaments, 
tendons,  and  membranes — in  fact  in  all  living  tissues  almost 
without  exception.  Ruysch  therefore  may  claim  the  credit  of 
establishing  the  ubiquity  of  the  vascular  system. 

Ruysch  followed  Swammerdam  in  injecting  a  substance  which 
cooled  in  the  vessels,  and  thus  ensured  the  permanence  of  the 
preparation.  His  first  attempts  exceeded  the  achievements  of 
Swammerdam,  and  vessels  of  extreme  tenuity  became  visible  to 
the  naked  eye.  He  was  hence  able  to  discover  the  thin  fibrous 
periosteum  of  the  auditory  ossicles  (1697),  which  had  up  to  that 
time  been  regarded  as  naked,  the  vasa  vasorum,  the  capillaries 
of  the  bronchial  tubes,  and  the  vessels  of  the  choroid  and  other 


THE  HISTORY  OF  ANATOMICAL  INJECTIONS       305 


nembranes.    It  is  na^tural  that  he  should  exalt  the  significance  of 
lis  own  discoveries,  and  that  he  should  regard  this  most  subtle 
wid  intrusive  vascular  system  as  having  an  existence  per  se.     In 
L723,  almost  at  the  end  of  his  life,  his  enthusiasm  for  injections 
s  expressed  in  the  following  passage  :    '  Vah  quantum  est,  quod 
lescivimus  ante  repletionis  artem  !    quantum  didicimus  per  illam  ! 
3  mirus  naturae  in  ultima  vascula  olim  invisibilia  appulsus,  quo 
:am  abscondita  manifestantur  !     0  grata  repletio,  numquam  con- 
3emnenda  deinceps,  numquam  laudanda  satis  !  '     He  claims,  for 
example,  that  by  establishing  the  high  vascularity  of  the  cerebral 
cortex,  he  has  disproved  its  glandular 
nature  as  asserted  by  Malpighi,   and 
liis  substitution  of  the  vascular  for  the 
glandular  theory  of  the  cortex  tends  to 
obscure  the  important  advance  which 
was  actually  made.     He  is  unusually 
and  unfortunately   emphatic  on  this 
point.     Of  all  the   discoveries   which 
he  has  been  making  for  forty  years, 
he  says  in  1705,  the  most  important 
is  the  proof  that  the  cerebral  cortex  is 
not  a  gland  but  only  a  mass  of  blood- 
vessels.    His  injections  were  so  refined 
that    the    parenchymatous    elements  ^^-  ^• 
were    overlaid   and   obscured  by  the 
multitude  of  vessels  which  sprang  into  view.     This,  and  doubtless 
certain  extravasation  effects,  induced  him  in  1696  definitely  to 
formulate  the  doctrine  that  the  tissues  were  only  vascular  networks 
variously  arranged  ('  totum  corpus  ex  vasculis  ').    Already  in  1695 
H.  Ridley  had  stated  this  view,  and  as  late  as  the  eighteenth  century 
William  Hunter  was  still  teaching  that  the  glands  consisted  of  a 
concourse  of  vascular  elements  and  excretory  ducts  without  any 
definite  or  apparent  parenchymatous  basis.     Ruysch  had  injected 
the  arteries  and  veins  of  certain  glands,  macerated  them  in  water, 
and  then  um-avelled  them  without  finding  anjrbhing  but  a  tangle 
of  injected  vessels.     Ruysch,  however,  did  not  hold  that  a  gland 
was  formed  wholly  of  blood-vessels,  but  admitted  that  between 
the  extremities  of  the  vessels  there  existed  a  neutral  pulpy  sub- 
stance.   He  believed,  further,  that  the  blood  was  poured  directly 
into  the  factors  of  the  excretory  ducts  of  the  glands,  since  his 


Periosteum  of  the  auditory 
ossicles  injected  by  Ruysch  (1697). 


3()()      THK    HISTORY   OF  ANATOMICAL  INJECTIONS 

wax  injection  thrown  into  an  artery  cnicrgcd  by  the  excretory 
duct  without  cntcrin;j;  any  intorniediato  non-vascular  tiHSue  or 
spaces  on  tin'  way.  '  Tlic  ceraceous  injection  of  Huysch  being 
artfully  impelled  makes  its  way  [via  the  uriniferous  tubules]  even 
into  the  jiclvis  of  the  kidney  from  the  arteries'  (Boerhaave). 
'  This  w^as  the  principal  ground  for  the  famous,  but  now  exploded 
theory  of  the  existence  of  exhalant  arteries  with  open  mouths, 
which  in  the  secretory  glands  opened  directly  into  the  excretory 
ducts  '  (Bowman).  On  this  view  there  was  no  need  for  a  paren- 
chyma, but  Ruysch  was  unable  to  deny  the  existence  of  a  non- 
vascular tissue  in  the  lingual  glands,  although  he  maintained  that 
the  lobules  of  the  hver  consisted  of  bunches  of  vessels  without 
any  parenchyma.  His  views  on  the  ultimate  structure  of  animal 
tissues  were  strongly  supported  by  Cowper  and  Nuck. 

As  a  result  of  Ruysch's  experiments  there  arose  a  '  despotism 
of  injections  ',  which  attributed  the  functions  of  the  tissues  to  the 
specific  disposition  and  peculiarities  of  their  vascular  supply.  This 
disposition  was  believed  to  exist  in  infinite  variations,  and  the 
diverse  activities  of  the  tissues  were  explained  as  the  necessary 
consequence  of  such  variations.  Malpighi,  who  had  correctly 
stated  the  relations  betw-een  glandular  tissue  and  its  blood  supply, 
was  thus  strongly  opposed  and  beaten  down  by  Ruysch  and  his 
follow^ers,  who  denied  the  very  existence  of  glandular  tissue,  and 
saw  nothing  in  a  gland  but  a  subtle  complex  of  blood  capillaries. 
Two  exceptions  to  this  vascular  autocracy  were  admitted — the 
ovary  and  the  testis,  the  fabric  of  which  Ruysch  was  never  able 
to  prepare  by  injection,  and  he  concluded  therefore  that  red  blood 
did  not  penetrate  into  the  essential  parts  of  these  glands.  Nuck 
and  Cowper  (1697)  also  failed  to  inject  the  testis. 

Another  consequence  of  Ruysch's  injections  was  an  improved 
method  of  preserving  bodies  from  putrefaction,  for  which  his  name 
became  famous  in  all  the  schools  of  Europe.  In  1666,  by  order 
of  the  Dutch  Government,  Ruysch,  who  was  then  in  his  twenty- 
eighth  year,  undertook  to  preserve  by  vascular  injection  the  body 
of  Vice-Admiral  Sir  William  Berkeley,  whose  ship  had  been 
captured,  and  the  admiral  himself  killed,  when  leading  the  van 
in  the  gallant  but  hopeless  contest  of  June  1.  The  experiment, 
though  made  more  difficult  by  the  putrefaction  of  the  body  and 
the  admiral's  wounds,  was  wholly  successful,  and  the  Dutch 
chivalrously  returned  the  body  to  England  in  condition  as  fresh, 


THE  HISTORY  OF  ANATOMICAL  INJECTIONS      307 

ve  are  told,  as  that  of  an  infant.  Ruysch  was  encouraged  to 
ittempt  other  preparations  of  a  similar  nature  for  his  own  Museum, 
vhich  has  been  described  as  a  '  perfect  necropolis,  all  the  inhabi- 
ants  of  which  were  asleep  and  ready  to  speak  as  soon  as  they 
vere  awakened '.  Ruysch  himself  says :  '  Sunt  mihi  parvula 
jadavera,  a  viginti  annis  balsamo  munita,  quae  tam  nitide  sunt 
jonservata,  ut  potius  dormire  videantur,  quam  exanimata  esse 
jorpuscula.'  Entire  bodies  of  infants  and  adults  were  mummified 
jy  vascular  injection  of  possibly  some  preparation  of  arsenic,  with 
^hat  success  the  following  paraphrase  of  an  eloquent  passage  in 
Eloy  provides  ample  testimony  :  ^ 

All  the  bodies  which  he  injected  preserved  the  tone,  the 
ustre,  and  the  freshness  of  youth.  One  would  have  taken  them 
:or  living  persons  in  profound  repose — their  limbs  in  the  natural 
paralysis  of  sleep.  It  might  almost  be  said  that  Ruysch  had 
iiscovered  the  secret  of  resuscitating  the  dead.  His  mummies 
w^ere  a  revelation  of  life,  compared  with  which  those  of  the 
Egyptians  presented  but  the  vision  of  death.  Man  seemed  to 
continue  to  live  in  the  one,  and  to  continue  to  die  in  the  other. 

A  quaint  manifestation  of  Ruysch's  interest  in  injections  is  to 
be  found  in  his  Museum.  The  skeletons  are  thrown  into  dolorous 
attitudes  and  provided  with  anatomical  pocket  handkerchiefs  of 
injected  omentum,  their  wrists  are  adorned  with  organic  and 
injected  frills,  and  even  the  bladder  used  to  seal  the  mouths  of 
the  jars  has  been  carefully  injected.  Of  the  methods  by  which 
his  wonderful  preparations  were  produced  we  have  but  scanty 
knowledge.  Even  his  friend  Boerhaave,  who  was  occasionally 
present  when  Ruysch  was  injecting,  is  silent  as  to  his  methods. 
When  Peter  the  Great,  on  his  second  visit  to  Amsterdam,  acquired 
Ruysch's  collections  in  1717,  having  first  seen  and  coveted  them 
in  1698,  it  is  said  that  he  stipulated  that  the  preparations  should 
be  accompanied  by  a  description  of  the  methods  of  the  preparateur. 
This  was  accordingly  drawn  up  by  Ruysch,  and  ultimately  found 
its  way  into  the  library  of  the  University  of  St.  Petersburg, 
founded  in  1 81 9.  In  1742  an  account  of  this  manuscript,  based 
on  the  copy  in  Ruysch's  handwriting,  was  published  by  Joannes 
Christophorus  Rieger.  Rieger  had  been  in  the  employ  of  Peter 
the  Great,  after  whose  death  in  1725  he  retired  to  Holland,  where 

1  Obviously  inspired,  however,  by  a  passage  in  Fontenelle's  Moge  de  Ruysch, 
published  in  1731,  which  itself  owes  something  to  the  rhetoric  of  Ruysch  himself. 


ms      THK  niSTOIlN    OK  ANATOMICAL  INJECTIONS 

lie  liv(^d  over  a  bookseller's  shop,  and  compiled  the  work  which 
includes  the  description  of  Jiuyseh's  methods.  He  states  that  he 
saw  the  manuscript  by  permission  of  the  President  of  the  Imperial 
Academy  of  St.  reters})ur<]5.  Now,  tlu;  Acadc^my  was  only  founded 
in  1725,  so  that  ho  nuist  have  examined  the  manuscript  before 
his  retirement  to  Holland,  and  after  the  death  of  Peter  the  Great. 
It  seems  probable  that  Ruysch's  collections  and  manuscript 
were  for  a  time  handed  over  to  the  care  of  the  Academy,  since 
a  description  of  the  ])reparations  was  issued  by  that  body  in  1741.^ 

From  Riegcr  we  learn  the  following  details  of  Ruysch's  pro- 
cedure. Macerate  the  body  to  be  injected  in  cold  water  for  a  day 
or  two.  Slit  up  the  aorta  and  vena  cava  and  press  out  the  blood, 
and  immerse  the  body  in  hot  water  from  four  to  six  hours.  The 
injection  used  is  in  the  winter  suet  or  tallow,  and  in  the  summer 
a  little  white  wax  is  added.  Another  mass  may  be  prepared  by 
mixing  wax,  turpentine,  and  resin.  The  colour  employed  is  ver- 
milion, or  spirits  of  wine  and  vermilion,  and  the  larger  vessels 
are  afterwards  filled  with  wax  to  prevent  the  escape  of  the  spirit. 
Two  tubes  are  fixed  in  the  aorta,  one  being  directed  forwards  and 
the  other  backwards,  and  the  vena  cava  is  ligatured.  The  vessels 
are  filled  by  means  of  two  heated  syringes,  and  the  subject  is  to 
be  moved  about  continually  in  cold  water  after  the  operation  to 
prevent  the  gravitation  of  the  heavy  vermiUon  whilst  the  mass  is 
setting.  Having  been  injected  the  specimen  is* preserved  in  diluted 
alcohol,  which  Ruysch  distilled  himself  from  barley.  Black  pepper 
was  added  to  assist  its  penetrative  power.  The  strength  of  the 
alcohol  was  only  about  67  per  cent. — ^too  weak  for  the  purposes 
of  permanent  conservation,  although  no  deterioration  was  observ- 
able during  Ruysch's  own  lifetime.  Hyxtl  suggests  that  the  secret 
was  handed  over  to  Rieger  when  it  was  seen  that  the  preparations 
were  becoming  worthless,  and  we  have  the  statement  of  Jesse 
Foot,  pubUshed  in  1794,  that  '  I  saw  the  preparations,  belonging 
to  Ruysch,  which  are  deposited  in  the  Museum  at  Petersburg, 
going  apace  into  decay ',  and  before  this,  in  1748  Lieberkiihn, 
who  had  examined  examples  of  Ruysch's  injection  mass,  con- 
sidered it  too  fluid  to  last,  whilst  the  preparations  themselves  did 
not   stand   microscopic   examination.      In   order   to   display  the 

1  Ruysch's  second  collection  was  catalogued  by  himself  in  1724  and  1728, 
and  by  Abraham  Vater,  who  had  been  one  of  his  pupils,  in  1736-^0. 


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THE  HISTORY  OF  ANATOMICAL  INJECTIONS      309 

injected  microscopic  vessels  Kuysch  cleared  the  tissues  with  oil 
of  lavender  or  turpentine. 

It  is  obvious  in  the  Rieger  document  that  Ruysch  conceals 
more  than  he  discloses.  In  the  subsequent  literature  there  are 
many  conjectures  by  various  anatomists  as  to  the  composition  of 
Ruysch's  media,  but  none  of  them  carry  the  authority  or  con- 
viction of  the  definite  if  meagre  statements  of  Rieger.  Besides 
injection,  Ruysch  was  very  successful  in  the  use  of  the  inflation 
method.  The  lymphatic  vessels  were  inflated  by  means  of  glass 
tubes,  dried,  and  dissected  so  as  to  expose  the  valves,  of  which 
Ruysch,  though  not  the  discoverer,  was  the  earliest  to  publish 
a  careful  study  in  his  first  paper  issued  in  1665. 

From  Ruysch  to  Lieberkiihn,  who  established  the  importance 
of  microscopic  injections,  there  is  an  extensive  literature — not, 
however,  of  sufficient  interest  to  be  dealt  with  other  than  briefly. 
Blankaart  ^  seems  to  have  been  the  first  to  demonstrate  by  injec- 
tions that  the  connexion  between  arteries  and  veins  Avas  not  by 
a  spongy  parenchyma  but  by  capillaries,  a  conclusion  alreadj' 
reached  by  Malpighi,  and  confirmed  a  few  years  later  by  Lange  - 
and  Leeuwenhoek  (1689).  Caspar  Bartholin,^  the  son  of  Thomas 
and  the  grandson  of  old  Caspar,  published  two  works  dealing  with 
injections  when  he  was  still  very  young,  in  the  earlier  of  which 
he  was  accused  by  his  contemporaries  of  subtle  plagiarism.  His 
advance  on  de  Graaf  is  that  he  was  the  first  to  recommend 
systematically  flushing  out  the  vessels  with  water  before  throwing 
in  the  coloured  injection,  thus  anticipating  a  modern  refinement. 
He  proceeds  as  follows  :  the  part  is  steeped  in  tepid  water  in 
order  to  soften  the  clotted  blood,  which  is  then  removed  from  the 
vessels  by  an  injection  of  warm  water.  This  preliminary  operation 
is  facilitated  by  ligaturing  the  return  vein  and  suddenly  releasing 
the  ligature,  when  the  sharp  rush  of  the  hot  water  carries  the 
blood  with  it.  He  claims  for  this  method  a  finer  and  more  general 
injection,  but  this  was  questioned  by  later  \vriters,  who  asserted 
that  the  water  left  the  vessels,  and  produced  misleading  infiltra- 

^  Steven  Blankaart  (1650-1702),  Tractatus  novus  de  circulatione  sanguinis, 
Amsterdam,  1676,  12mo. 

2  Christian  Johannes  Lange  (1655-1701),  Disputatio  de  circulatione  sanguinis, 
Leipzig,  1680,  4to. 

'  Caspar  Bartholin  (1655-1738),  De  diaphragmaiis  slructura  nova,  Paria, 
1676,  8vo.    Admintstrationum  anatomicarum  specimen,  Frankfurt,  1679,  8vo. 

•2391  Y 


MO      THE  HISTORY  OF  ANATOMKWL  IN.IKCTIONS 


tioMs  in  the  surrounding  tissues.  Bartholin's  ;i|)i)aiatus  was  either 
a  niodilieil  sviiJiji;e  or  a  specially  construeted  niacliinc^  devised  to 
facilitate  his  irrigatioii  experiments.  Tlu^  ]>rinciple  of  both,  how- 
ever, is  the  same,  viz.  that  an  unlimited  Kup])ly  of  the  injection 
riuid  can  he  forced  into  the  vessels  without  withdrawing  the  nozzle 
from  tlie  artery.  This  is  effected  by  a  T-piece  and  valves,  hut  he 
admits  tliat,  owing  to  temperature  difficulties,  his  contrivance  is 
not  suitable  for  wax  injection,   for   which   tlie   ordinary  syringe 

must  still  be  used.  Barthohn  was  the 
first  to  devise  an  injection  ap|)aratus  with 
a  continuous  feed,  but  it  found  little 
favour  until  Straus-Durckheim  in  1843, 
and  Robin  in  1849,  developed  the  idea 
and  recommended  a  more  complex  form 
of  it.  It  is  to  be  noted  that  de  Graaf 
and  Bartholin  are  the  first  to  figure  in- 
jection syringes.  Bartholin  injected  air, 
water,  and  various  coloured  liquids,  but 
does  not  favour  wax.  He  produces  a 
green  by  mixing  gamboge  and  indigo,  as 
already  described  by  de  Graaf. 

Duncan  is  perhaps  the  earliest  wTiter 

definitely  to  advocate  the  use  of  mercury,* 

and  to  contrast  the  arteries  and  the  veins 

by  injecting  them  with  different  colours. 

Fig.  6.     Injection  appliances  He  employs  usually  melted  wax  thinned 

of  Caspar  Bartholin  (1679).    The  ^^.j^j^  turpentine  and  oil,  and  also  a  black 

liquid.  His  wax  injection  is  '  according 
to  the  method  of  M.  Swammerdam', 
except  that  he  recommends  that  as  the  wax  hardens  quickly 
it  is  better  to  inject  the  animal  when  it  is  still  ahve  !  He 
refers  to  Swammerdam  also  as  experimenting  with  mercmry  for 
injections.  Duncan  injected  one  colour  first  by  the  jugular  vein, 
and  then  another  colour  by  the  vertebral  artery.  '  Thus  the 
arteries  and  veins  are  easily  distinguished  by  their  different 
colour ',  and  the  communications  between  the  arteries  and  veins 
are  demonstrated.  The  experience  which  the  great  comparative 
anatomist     Duverney    derived    from    injections    was    strangely 

1  Daniel  Duncan  (1649-1735),  Explication  nouvelle  et  mecanique  des  actions 
animales,  Paris,  1678,  12nio. 


syringe  can  be  recharged  without 
disconnecting  the  apparatus. 


THE  HISTORY  OF  ANATOMK^AL  INJECmONS       :U1 

unfortunate/  In  two  papers  written  in  1679  and  1683,  but  not 
published  until  1733,  he  anticipates  the  speculation  of  Ruysch 
by  stating  that  the  so-called  solid  tissues  of  the  body  are 
nothing  but  a  miraculous  concourse  of  different  vessels,  and  that 
^vhen  all  the  liquids  have  been  expressed  from  a  tissue  nothing 
s  left  but  canals  and  vesicles.  In  the  Stork  his  injections  failed 
to  reveal  the  lacteal  vessels  or  the  thoracic  duct,  the  occurrence 
:)f  which  in  Birds  he  therefore  doubts.  An  injection  thrown  into 
the  mesenteric  vein  passes  into  the  cavity  of  the  intestine,  and 
conversely  if  a  portion  of  the  gut  be  filled  with  milk,  ligatured  at 
both  ends,  and  then  compressed,  the  milk  is  forced  into  the 
mesenteric  vein.  He  holds  that  the  chyle  in  the  Bird  passes  via 
the  mesenteric  veins  to  the  liver. 

Dismissing  Charleton,^  who  refers  to  '  various  manual  opera- 
Dions  besides  meer  dissection  ',  such  as  '  inflations,  injections  of 
livers  liquors  by  syringes  ',  Simon  Lescot  (c.  1615-90),  the  surgeon 
^vlio  is  supposed  to  have  introduced  Swammerdam's  wax  method 
nto  France  c.  1680,  and  de  Heyde,  who  practised  physiological 
njections  on  living  dogs,^  we  come  to  Bidloo,*  who  inaugurated 
Ml  injection  experiment  which,  applied  as  it  afterwards  was  to 
the  blood  system,  became  very  popular  in  the  eighteenth  centiu'y. 
He  filled  the  lungs  with  '  fused  bismuth  ',  afterwards  removing 
the  soft  parts  by  corrosion,  thus  producing  a  permanent  cast  in 
metal  of  the  cavities  of  the  lung.  By  '  fused  bismuth  '  must  be 
understood  not  the  pure  metalUc  substance,  which  melts  at  too 
liigh  a  temperature  for  the  purpose,  but  a  complex  mixture  con- 
taining bismuth  and  mercury,  some  preparations  of  which  had 
ilmost  the  consistency  of  wax. 

The  English  comparative  anatomist  Samuel  Collins  ^  has  never 
ichieved  the  reputation  which  his  work  undoubtedly  deserves. 
It  is  contemptuously  regarded  by  Hutchinson  as  '  of  less  value 
than  the  head  that  is  placed  before  it ' — referring  to  the  beautiful 

1  Joseph  Guichard  Duverney  (1648-1730),  Histoire  de  V Academie  Royale  des 
Sciences,  Paris,  1733,  4to,  T.  1,  pp.  278  and  363. 

2  Walter  Charleton  (1619-1707),  Enquiries  into  Human  Nature,  London, 
1680,  4to. 

'  Anton  van  der  Heyde,  Centuria  Observationum  Medicarum,  Amsterdam, 
1683,  8vo. 

*  Govard  Bidloo  (1649-1713),  Anatomia  humani  corporis,  Amsterdam, 
1685,  fol. 

5  Samuel  Collins  (1618-1710),  A  System  oj  Anatomy,  London,  1685,  2  vols.,  fol. 


:n2     vwK  nisToin'  of  axa^'omical  inmkchons 

cJi^iiiN  ill;:;  of  Collins  by  h^iiilionic  which  coiLstitutcs  tlie  frontis 
piece,  ('ollins,  liowcvcr,  made  littki  us(^  of  iiijcctioiiH,  and  hi.s  fev 
exj>eiinients  serxcd  hut  to  mislead  him.  He  employed  white  wa: 
and  vermilion,  and  as  a  result  adopted  views  on  the  relations  o 


Fig.  7.    The  lymphatics  of  the  urogenital  organs  injected  with  mercurj^ 
by  Anthony  Nuck  (1691). 

the  cephalic  and  genital  arteries  and  veins  contrary  to  the  know- 
ledge even  of  his  own  time.  His  contemporary  Nuck,^  on  the 
other  hand,  melded  the  syringe  with  admirable  results.  He 
injected  red  colomred  wax  and  coloured  fluids.  The  wax  was 
mixed  with  oil  to  make  it  sufficiently  fluid  to  reach  the  finest 
branches,  but  his  chief  medium  was  mercury,  wliich  he  was  the 
^  Anthony  Nuck  (1650-92),  De  ductu  salivali  novo,  Leyden,  1685,  16mo. 
Adenographia  curiosa,  Lej-den,  1691,.  8vo. 


THE  HISTORY  OF  ANATOMICAL  INJECTIONS     :J13 

irst  to  put  to  extensive  use.  He  also  experimented  with  an 
imalgam  of  mercury  and  lead  or  tin,  and  a  preparation  called 
iinctura  mercurialis,  the  composition  of  which  is  not  given. 
*^uck's  general  description  of  the  lymphatics  is  one  of  the  most 
complete  before  Mascagni.  He  investigated  the  structure  of  the 
lecretory  glands  by  injecting  their  ducts,  lymphatics,  and  arteries 
md  veins,  and  also  by  inflation.  He  was  the  first  to  demonstrate, 
3y  means  of  mercury  injection,  that  the  lymph  stream  passes 
;hrough  and  beyond  the  lymphatic  glands  and  is  not  interrupted 
3y  them.  He  was  also  the  first  thoroughly  to  ex])lore  the 
;onstitution  of  the  secretory  and  lymphatic  glands  and  of  the 
ymphatic  system  by  mercury  injections.  But  his  experiments  led 
lim  into  numerous  errors.  He  found  that  mercury  passed  from 
;he  lacteals  and  lymphatics  into  the  arteries,  and  concluded  from 
}his  that  the  lymphatics  arose  from  the  arteries.  In  the  same 
^ay  he  deduces  that  the  ramifications  of  the  arteries  are  connected 
ip  with  the  factors  of  the  salivary  ducts.  He  inflated  the  arteries 
3f  the  spleen  and  kidney  and  saw  air  pass  into  the  lymphatics, 
md  hence  believed  that  the  lymphatics  were  veins.  It  was  not 
jntil  1757  that  Monro  secundus  finally  demonstrated  that  Nuck's 
3iTors  were  due  to  extravasation  effects.  A  similar  misconception 
was  based  on  his  injection  with  mercury  of  the  glandular  lobules 
af  the  mammary  gland,  when  the  mercury  found  its  way  into  the 
blood-vessels — especially  the  arteries. 

The  botanist  Camerarius  ^  was  one  of  the  pioneers  of  mercury 
injection.  He  injected  the  testis  from  the  vas  deferens,  and  other 
organs,  with  milk,  wax  of  diverse  colours,  and  mercury,  and  also 
inflated  them  with  air.  Compare  the  preceding  and  later  work  on 
the  injection  of  the  testis  of  Perrault,  King,  and  Haller.  The 
inevitable  mercury  extravasation  induced  the  belief  that  there 
was  a  connexion  between  the  seminal  tubules  and  the  lymphatics. 
In  1686  A.  van  der  Heyde  injected  the  gastro- vascular  canals  of 
Aurelia  with  a  black  liquid.  Contrary  to  expectation  Leeuwenhoek  ^ 
does  not  appear  to  have  practised  injections  himself,  but  he 
mentions  injections  of  hot  wax,  and  gives  the  following  interesting 
description  of  a  mercury  injection :    '  A  certain  doctor  of  Physic, 

1  Rudolphus  Jacobus  Camerarius  (1665-1721),  '  De  nova  vasorum  semini- 
ferorum  et  lymph aticorum  in  testibus  communicatione ',  Ephem-  Acad-  Nat. 
Cur.,  Ann.  1686,  1688,  Niirnberg,  1687,  1689.    Dec.  2,  Ann.  7,  p.  432,  4to. 

*  Anthony  van  Leeuwenhoek  (1632-1723),  Vervolg  der  Brieven  geschrcren  aan 
de  Koninglijke  Societeit  tot  London,  Delft",  1689,  p.  336,  4to, 


:ni     TMK  nls'^()^^'  or  anatomi(,^al  injk(TIoxs 

lo  wlioiii,  iunon^  other  (mthoiih,  I  had  sliouii  tlic  eiiculatioii  of 
the  blood,  told  tnc  tliat  thiH  eircidatioii  had  also  hct'ii  exliibited 
to  him  by  a  cliirmj^ical  j^cntloniaii  ;  and  on  my  ticsiring  to  know 
how  it  was  shown  to  liim,  \\v  said  by  injecting  quicksilver  into 
an  artery,  wliieh  eireulated  back  again  througli  a  vein  ;  but 
when  1  asked  him  how  thoy  were  aysured  that  one  of  the  vesHcls 
in  which  the  ex])eriment  was  made  was  an  artery,  and  tlie  other 
a  vein,  lie  answered  that  tliey  were  not  certain  as  to  that  point. 
I  also  asked  him  wliat  was  the  size  of  the  vein  in  whi(;h  the 
quicksilver,  so  injected,  was  circulated  ;  to  which  he  aiLswered, 
that  it  was  above  a  thousand  times  larger  than  those  vesHels  in 
which  he  had  seen  the  circidation  of  the  blood  at  my  house.' 
Leeuwenlioek  was  not  convinced  by  this  exjxiriment,  holding 
that  it  was  possible  the  injection  might  return  by  an  artery 
instead  of  a  vein,  and  thus  not  necessarily  demonstrate  the 
circulation.  On  the  other  hand,  Ray  *  believes  that  the  structure 
of  the  body  may  easily  be  detected  by  blowing  air  into  the 
vessels  and  drying  the  preparation,  or  by  injecting  melted  wax 
or  quicksilver  with  syringes.  He  accepts  the  doctrine  of  the 
tubular  (i.  e.  non-parenchymatous)  structure  of  the  glands,  and 
considers  it  wonderful  that  '  all  the  glands  of  the  body  should  be 
congeries  of  various  sorts  of  vessels  cur'd,  circumgyrated,  and 
complicated  together,  whereby  they  give  the  blood  time  to  stop 
and  separate  through  the  pores  of  the  capillary  vessels  into  the 
secretory  ones,  which  afterwards  all  exonerate  themselves  into  one 
common  ductus '.  In  his  work  on  the  brain  Ridley  ^  found 
injection  experiments  very  helpful.  He  says  :  '  Other  bodies  have 
been  introduc'd  by  injection,  as  tinged  wax  and  mercury,  the  first 
of  which  by  its  consistence  chiefly,  the  other  b}"  its  permanent 
nature  and  colour,  contribute  mightily  towards  bringing  to  view 
the  most  minute  ramifications  of  vessels,  and  secretest  recesses  of 
Nature.'  He  prefers  mercury  to  wax,  the  latter  being  too  coarse 
for  the  finest  vessels.  '  By  an  injection  with  mercury  I  find  scarce 
any  nerves  but  what  hath  some  such  small  ramifications  of  blood- 
vessels in  them.'  His  '  chief  hopes  '  were  based  on  mercury,  but 
he  is  almost  the  first  to  recognize  that  extravasations  might  make 
mercury  injections  '  altogether  useless  '. 

1  John  Ray  (1628-1705),  The  Wisdom  of  God  manifested  in  the  works  of  the 
Creation,  London,  1691,  8vo. 

2  Humphrey  Ridley  (1653-1708),  The  Anatomy  of  the  Brain,  London,  1695, 8vo. 


1 


THE  HISTORY  OF  ANATOMICAL   INJECTIONS      'Mry 

The  Ruyschiaii  art  found  an  enthusiastic  su])porter  in  tlie 
arch-plagiarist  Cowper.^  Besides  inflating  the  vessels  with  air  and 
drying  the  preparation,  he  used  as  injection  masses  plaster  of 
Paris,  wax,  and  mercury.  With  the  latter  he  injected  the  biliary 
ducts,  kidney,  lymphatic  system,  and  carotid  artery.  He  demon- 
strates by  mercury  injections  that  the  maternal  blood-vessels 
penetrate  into  the  placenta,-  but  although  he  found,  as  related 
by  Drake,  that  mercury  injected  into  the  uterine  artery  of  a  cow 
passed  via  the  cotyledons  into  the  foetus,  he  hesitates  definitely 
to  commit  himself  to  the  continuity  of  maternal  and  foetal  blood. 
There  was  a  strong  tendency  at  the  time  to  believe  so  natural  an 
assumption,  as  witness  the  following  passage  from  Drake  (1707)  : 
'  On  the  other  hand,  if  the  arteries  of  the  uterus  were  continued 
to  the  veins  of  the  same  part,  and  those  of  the  foetus  in  like 
manner,  without  communicating  with  each  other,  their  confluence 
in  the  placenta  seems  to  be  altogether  impertinent  and  of  no  use, 
and  the  umbilical  arteries  and  vein  fram'd  for  no  other  service 
or  purpose,  than  to  give  the  blood  room  for  an  idle  sally.'  Cowper 
injected  mercury  into  the  lactiferous  tubes  of  the  mammary  gland, 
and  he  confirms  Nuck  in  finding  it  emerge  by  the  blood-vessels. 
His  injection  experiments  lead  him  into  many  other  errors,  as,  for 
example,  when  he  describes  a  mass  thrown  into  the  renal  artery 
escaping  by  the  ureter.  Mercury  is  used,  and  also  variously 
coloured  wax,  to  inject  other  than  vascular  cavities,  e.  g.  the 
Fallopian  tubes.  The  arteries  of  a  foetus  are  demonstrated  by 
a  wax  injection.  He  uses  wax  of  four  different  colours  to  inject 
the  liver — hepatic  artery,  red  ;  portal  vein,  '  dark  '  colour  ;  post- 
caval, '  distinguishable  '  colour  ;  and  bile  duct,  yellow.  The  liver 
lobules  were  next  roughly  separated,  slightly  macerated,  and  the 
parenchyma  removed  with  a  stiff  brush  of  hog's  bristles.  Wax  is 
njected  into  the  salivary  and  pancreatic  ducts  to  ascertain  how 
these  ducts  are  formed  within  the  gland.  Cowper  also  filled  the 
pulmonary  passages  with  '  block  tin  ',  and  macerated  off  the  soft 
parts.  These  preparations  of  liver  and  lung  are  among  the  earliest 
3orrosion  experiments  of  which  we  have  any  record,  but  the  idea 
s  obviously  borrowed  from  Bidloo,  who  in  his  turn  owes  something 

>  William  Cowper  (1666-1709),  The  Anatomy  oj  Humane  Bodies.  Oxford,  1698, 
ol.     Some  copies  are  dated  1697,  but  the  work  was  not  published  until  May.  1698. 

2  Monro  concludes  that  on  this  point  Cowper  is  speaking  a  priori,  and  not 
rom  what  he  actually  saw. 


:M(>      'IMiK   HISTOm'  OF  AXATO.MKAI.   IN.JK(T10NS 

to  tlie  excaniation  incpiiralions  of  Spigclius  and  GlisHon  described 
in  lf)27  and  M)r)4.  Block  tin  in  the  scventocntli  century  was 
a  more  or  less  \)\uc  tin  as  now,  and  lience  on  account  of  its  Ingli 
melting-|)()int  could  not  have  been  employed  as  Cowper  states. 
He  must  tliereforc  lunc  made  use  of  an  alloy. 

A  sliort  but  important  ])aper  by  Hond)erg  was  written  in  1699, 
but  not  ])ublished  until  1702.*  Honiberg  ex|)erimente(l  with  wax, 
mercuny,  and  turpentine — not  th(^  modern  oil  of  turj)entine,  but 
a  resin  of  the  consistency  of  honey.  He  is  also  the  first,  if  not  to 
introduce,  at  least  to  demonstrate  the  practicability  of  injecting 
metals  of  low  fusibility.  His  metal  injection  consisted  of  equal 
])arts  of  lead,  tin,  and  })ismuth,  which  remains  liquid  at  a  tem- 
perature below  the  scorching-point  of  paper.  Subsequently  Newton 
and  d'Arcet  found  that  by  altering  the  proportions  of  these  three 
ingredients,  and  ))rinci])ally  by  increasing  the  percentage  of  bis- 
muth, the  melting-point  was  reduced,  and  the  addition  of  mercury 
carried  the  reduction  still  further.  Homberg  finds  the  consistency 
and  melting-point  of  wax  and  turpentine  unsuitable  for  injection, 
whilst  mercury  escapes  from  the  smallest  cut.  He  believes  the 
principal  difficulty  to  be  air  in  the  vessels,  and  he  professes  to 
have  overcome  this  difficulty  by  means  of  a  complicated  piece  of 
apparatus  which  inflated  and  dried  the  vessels,  thus  facilitating 
the  escape  of  the  air.  This  apparatus,  however,  w^as  afterw^ards 
discarded  as  an  unnecessary  refinement,  and  he  next  tried  the 
interesting  experiment  of  exhausting  the  air  in  the  vessels  by 
means  of  an  air  pump  before  throwing  in  the  injection — a  method 
said  to  have  been  one  of  the  secrets  of  Ruysch.  Then  he  runs  in 
the  hot  metal  as  above,  and  after  it  has  cooled,  he  removes  the 
soft  parts  by  maceration  or  otherwise,  so  that  he  has  finally 
a  permanent  metal  cast  of  the  cavities  of  the  vessels.  He  is  ahve 
to  the  danger  of  attempting  such  an  injection  on  material  w^hich 
has  been  in  water,  and  he  recommends  that  such  material  should 
be  first  dried  for  a  day  in  the  air  pump.  Homberg  is  undoubtedly 
the  pioneer  of  the  so-called  corroded  preparation — a  method  which 
lost  interest  in  the  nineteenth  century  but  was  never  absolutely 
abandoned,  whilst  recently  the  popular  use  of  the  low  fusible 
alloys  has  resulted  in  its  re-introduction. 

In  the  first  half   of  the  eighteenth  century  the  sciences  of 

^  Guillaume  Homberg  (1652-1715),  '  Essais  sur  les  injections  anatomiques,' 
Hist,  de  VAcademie  Royale  des  Sciences,  Paris,  1702,  Ann.  1699,  8vo. 


THE  HISTORY  OF  ANATOMK^AL  INJECTIONS     317 

Anatomy  and  Physiology  were  making  great  progress  principally 
by  means  of  injection  methods.  All  the  literature  of  the  period 
refers  to  the  still  fascinating  doctrine  of  the  circulation,  and  the 
injection  syringe  was  the  most  popular  and  trusted  instrument  of 
the  time.  Hovius  ^  worked  out  the  circulation  in  the  iris,  ciliary 
process,  and  lachrymal  gland  by  injections  of  wax  and  mercury. 
He  describes  vessels  in  the  cornea,  although  none  are  present  in 
a  state  of  health,  and  professes  also  to  have  discovered  vessels 
in  the  lens  and  humours  of  the  eye,  and  to  have  established 
a  definite  circulation  in  those  parts.  Mery's  injections  of  air  and 
water  ^  represent  a  very  definite  advance  towards  an  understanding 
of  the  mechanism  of  respiration,  but  the  unsoundness  of  his 
methods,  as  pointed  out  by  G.  B.  Biilffinger  in  1732,  was  against 
a  more  important  result. 

Vieussens'  injection  experiments  ^  can  only  be  generally  con- 
demned, and  it  is  doubtful  whether  he  obtained  a  single  vaUd 
result.  In  his  earlier  work  on  the  brain  he  used  spirits  of  wine 
©r  brandy  tinged  with  a  saffron  colour,  and  also  black  and  green 
liquors  and  ink,  but  he  gives  no  account  of  his  material  or  pro- 
cedure. Only  local  injections  are  described.  Thus  coloured  spirits 
of  wine  pumped  into  the  carotid  artery  reaches  the  longitudinal 
sinus  directly  from  the  arteries  of  the  dura  mater — an  error  after- 
wards corrected  by  Ruysch  and  Eau.  His  later  publications  are 
more  detailed  as  regards  injections,  and  he  is  now  using  mercury. 
His  injections  of  the  latter  substance,  obviously  conducted  at  too 
great  a  pressure,  result  in  deplorable  errors.  Mercury  thrown  into 
the  trachea  passed  into  the  blood-vessels  of  the  lungs,  if  injected 
into  the  mesenteric  artery  it  escaped  into  the  cavity  of  the  intestine, 
from  the  cystic  artery  it  found  its  way  into  the  gall-bladder,  and 
from  the  uterine  arteries  it  penetrated  into  the  cavity  of  the 
vagina  but  not  that  of  the  uterus.  As  the  result  of  his  injections 
he  deduces  that  there  is  a  connexion  between  the  arteries  and  the 
lymphatic  system.    The  lymphatic  duct  is  regarded  as  a  lymphatic- 

1  Jacobus  Hovius,  De  circulari  humorum  ocularium  motu,  Inaug.  diss.  Utrecht, 

1702,  4to.    Editio  nova,  Leyden,  1716,  8vo. 

2  Jean  de  Mery  (1645-1722),  Histoire  de  V Acad^mie  Eoyale  des  Sciences,  Paris, 

1703,  Ann.  1700.    Ibid.  1708,  Ann.  1707,  8vo. 

3  Raymond  Vieussens  (1641-1716),  Neurographia  Universalis,  Lyons,  1684, 
fol.  ;  Novum  vasorvm  corporis  humani  systema,  Amsterdam,  1705,  8vo.  ;  Disser- 
tatio  anatomica  de  structura  uteri  et  placentae  muliebris,  Cologne,  1712,  4to  ; 
Experiences  et  Refiexions  sur  la  structure  et  Vusage  des  visceres,  Paris,  1755,  8vo. 


:as     THK   HISTOUV  OK  ANATOMICAL  IX.IECTJONS 

arterial-nervous  apparatus,  and  lie  invents  a  new  elass  of  short- 
circuit  vesselH  to  explain  the  rapidity  with  whicii  liquids  taken 
into  tlie  stoinach  are  icnioved  by  the  kidneys,  to  tweount  for 
whieii,  lie  claimed,  the  Harveiaji  circulation  was  t(io  slow.  Again, 
he  injected  the  left  coronary  artery  with  coloured  brandy,  and 
describes  the  fluid  as  passing  '  without  violence  '  not  only  into 
the  entire  substance  of  the  left  auricle,  })ut  also  into  its  cavity. 
HencH'  we  have  another  of  his  theories  that  the  coronary  arteries 
and  veins  are  not  cojuiected  up  by  capillaries  but  by  the  cavities 
of  the  heart,  with  which  both  arteries  and  veins  communicate 
by  consjiicuous  aj)ertures.  An  exi)eriment  of  Vieussens  which 
obtained  wide  currency  and  belief  was  the  injection  of  the  carotid 
iu'tery  of  a  Uving  bitch  with  four  pounds  of  mercury.  He  holds 
that  the  mercury  '  without  breaking  any  vessels,  or  the  effusion 
of  one  drop  of  blood,  passed  through  the  placenta  surrounding  each 
whelp,  and  was  pushed  into  the  umbilical  vessels  themselves  '.  This 
experiment  was  twice  repeated  by  Monro  with  quite  different  (but 
correct)  results.  The  latter  states  that  the  mercury  travelled  into 
the  very  minute  branches  of  the  vessels  of  the  maternal  placenta, 
but  none  whatever  reached  the  umbilical  vessels  or  the  foetus. 

Noues,^  who  used  rectified  spirits  with  cinnabar  ground  in,  and 
speaks  of  injections  of  coloured  wax,  has  little  of  importance,  but 
Schacher  "  carries  Homberg's  experiment  a  stage  further,  and  is 
the  first  to  draw  the  injection  through  the  vessels  with  a  vacuum 
pump.  His  mass,  besides  starch,  is  pig's  fat,  mutton  suet,  and 
spermaceti,  each  in  combination  with  wax,  to  facilitate  the  filling 
of  the  smallest  vessels,  and  the  colours  are  vermihon,  red  oxide  of 
lead,  verdigris,  Florence  lake,  the  blue  extract  of  corn-flower,  and 
carmine.  At  this  time  Salzmann  ^  describes  injecting  the  thoracic 
duct  from  the  lymph  vessels  in  the  neighbourhood  of  the  renal 
vein,  and  Cheselden  *  injects  the  blood-vessels  with  wax  and  the 
tymphatics  with  mercury,  but  does  not  discuss  his  procedure.    He 

1  Guillaume  des  Noues,  Lettres  de  Mr.  de  Xoues  a  Mr.  Gxiillielmini,  Rome, 
1706,  8vo  ;  Avertissement  pmir  les  anatomies  toiites  nouvelhs  de  cire  coloree,  Paris, 
1717,  12mo. 

2  Polj'carpus  Gottlieb  Schacher  (1674-1737),  De  anatomica  praecipuarum  par- 
tium  administratione,  Leipzig.  1710,  4to. 

3  Johannes  Salzmann  (1672-1738),  Disseriatio  encheiresis  inveniendi  d-mtum 
thoracicum,  Strassburg.  1711,  4to. 

*  William  Cheselden  (1688-1752),  The  Anatomy  of  the  Humane  Body,  London, 
1713,  8vo. 


THE  HISTORY  OF  ANATOMICAL  INJECTIONS     319 

points  out  that  the  lymphatics  of  fish,  first  observed  by  T.  Bar- 
thoHn,  may  be  seen  in  the  mesentery  without  injection.  Injection 
as  a  method  of  preservation  was  practised  by  Ravius,^  many  of 
whose  preparations  in  the  Anatomy  Hall  at  Leyden  were  cata- 
logued by  his  successor,  B,  8.  Albinus,  in  1725. 

An  early,  if  not  the  earliest,  attempt  at  histological  injection 
is  described  by  Muys.-  He  first  of  all  removed  the  blood  from 
the  vessels  by  an  injection  of  warm  water,  and  then  threw  in 
a  coloured  Hquid.  His  object  was  to  ascertain  the  vascular  supply 
of  muscle  fibres,  and  he  wrongly  concluded  that  the  muscle  fibrillae 
were  tubular,  and  that  the  capillary  artery  discharged  '  a  part  of 
its  liquor '  into  the  cavities  of  the  fibrillae.  The  latter,  however, 
were  too  small  to  admit  the  coloured  blood  corpuscles,  which 
therefore  underwent  fragmentation  before  entering  the  fibre. 
A  figure  supports  this  flight  of  the  imagination.  The  short  paper 
by  Rouhault,  written  in  1718,^  is  important  and  exceptional,  since 
no  attempt  is  made  to  conceal  laboratory  methods.  He  says  the 
mass  usually  employed  is  a  mixture  of  hog's  lard,  white  wax, 
mutton  suet,  and  turpentine,  or  spirit  of  turpentine  charged  with 
a  little  wax.  His  colours  are  vermilion  for  arteries  and  verdigris 
or  indigo  for  veins,  and  he  claims  to  be  the  first  to  employ  different 
colours  for  arteries  and  veins.  In  this,  as  we  have  already  seen, 
he  is  mistaken.  Before  throwing  in  the  mass,  the  blood  is  cleared 
out  of  the  vessels,  and  the  body  warmed,  by  an  injection  of  tepid 
water,  after  which  the  body  is  wrapped  in  warm  linen.  The  above 
injection  does  not  pass  through  the  capillaries,  and  he  onty  uses 
it  to  demonstrate  the  coarser  circulation,  admitting  that  it  gives 
preparations  inferior  to  Ruysch's.  We  have  pointed  out  that 
Boyle  was  the  first  to  suggest  isinglass  as  an  injection  mass,  but 
Rouhault  may  claim  the  credit  of  demonstrating  its  importance. 
He  was  not  aware  of  Boyle's  work,  and  the  use  of  gelatine  was 
suggested  to  him  by  Mery.  He  dissolved  Ghent  glue  or  isinglass 
in  water,  and  in  1716  obtained  a  perfect  injection  of  the  finest 
vessels,  the  mass,  for  example,  passing  right  through  the  placenta 

^  Johannes  Jacob  Rau  (1668-1719),  Be  methodo  anatomen  docendi  et  diacendi, 
Leyden,  1713,  4to. 

2  Wyer  Guillaume  Muys  (1682-1744),  Journal  Litteraire,  La  Have,  Jan.,  Feb., 
1714,  8vo. 

3  Pierre    Simon    Rouhault    (ob.    1740).    '  ISur    les    injections    anatomiques  ', 
Histoire  de  VAcademie  Royale  des  Sciences,  Paris,  1720,  8vo,  Ann.  1718. 


320      THK   HISTORY  OK  ANATOMK  AL   INJKCTIONS 

uiul  cmcitjiiii^  !)>  t  l»o  veins.  He  cxhibitt'd  at  tlic  Academy  the  vchscIs 
of  the  placenta  ijij<'('t('(l  \n  itli  dittoront  colours.  Comparing  his 
prc|)arat.inns  u  itii  some  behoved  to  have  been  iiijec^ted  by  Ruys(;irs 
m(3th()(l,  he  considered  his  own  as  good  as  Rnysch's,  whieli  latter 
he  adds,  liad  nol  been  injected  with  wax.  Kouliauit  also  used 
spirits  of  wine  coloured  with  orchanette  or  carmijie,  which  pene- 
trates equally  well  into  the  finest  vessels,  but,  like  mercury,  the 
pre])arati()n  caniiot  be  dissecte<l  afterwards  without  bleeding,  and 
hence  this  method  is  only  suitable  for  whole  pre])arations. 

Boerhaave,^  though  less  a  ])ractical  anatomist  than  a  com- 
mentator, brings  to  bear  on  the  subject  so  intimate  a  knowledge 
of  his  contemporaries  and  their  methods  that  his  observations 
invite  attention.  He  does  not  believe  that  the  minutest  vessels 
are  demonstrated  even  by  '  the  most  subtile  coloured  liquor  '. 
For  example,  while  the  membranes  of  the  testis  are  richly  provided 
with  blood,  the  '  pulp  of  the  testicle  is  supphed  with  pellucid 
juices  by  arteriolae  much  smaller  than  the  sanguiferous,  and  into 
which  the  Ruyschian  injection  will  not  enter  '.  Jt  was  commonly 
noted  at  the  time,  in  the  case  of  vermilion  masses,  that  the  waxy 
or  other  vehicle  penetrated  into  vessels  which  would  not  admit 
the  vermilion,  and  Boerhaave  believed  that  the  pressure  exerted 
by  the  injector  forced  the  injection  into  vessels  which  were  not 
normally  traversed  by  red  blood,  '  since  no  part  of  the  cortex 
ever  appears  red  without  injection '.  He  thus  supports  Malpighi 
as  against  Ruysch  in  the  controversy  on  the  structure  of  the 
glands,  holding  that  Ruysch's  injections  unnaturally  dilated  the 
blood  capillaries  and  thus  obscured  or  even  destroyed  the  glandular 
tissue,  nor  will  he  assent  to  Ruysch's  view  that  injection  mass 
passes  from  the  arteries  into  the  excretory  ducts  of  a  gland. 
Boerhaave  makes  one  statement  the  origin  of  which  the  writer 
has  not  been  able  to  trace.  He  says  that  some  English  anatomists 
injected  the  carotid  arteries  with  urine  coloured  mth  ink  (a  medium 
employed  by  Malpighi),  and  found  that  the  nerves  of  the  brain 
were  tinged  with  the  colour.  When  one  of  the  nerves  was  sectioned 
it  appeared  full  of  black  specks,  which  M-ere  supposed  to  represent 
the  cavities  of  the  nerve  tubes.  It  will  be  remembered  that  at 
this  time  the  theory  of  Descartes  that  nerve  fibres  were  tubes 
transmitting  fluid  contents  was  generally  accepted. 

1  Herman   Boerhaave   (1668-1738),   A   method  of  studying  Physic,   London, 
1719,  8vo. 


THE  HISTORY  OF  ANATOMICAL  INJECTIONS.     321 

III  1720  Valentin^  gives  formulae  for  injecting  the  alveoli  of 
the  lungs  and  the  blood-vessels  with  low  fusible  metals,  the  flesli 
being  afterwards  boiled  away,  leaving  a  cast  of  the  injected 
cavities.  He  uses  also  a  wax  medium  made  of  white  wax  mixed 
with  mutton  suet  and  coloured  with  verdigris  or  vermilion,  which 
passes  through  capillaries  and  sets  when  cold.  Albinus,-  who 
claimed  that  the  art  of  injecting  coloured  liquids  into  the  vessels 
was  a  Belgian  invention,  employed  a  red  liquid  which  stiffened 
when  the  vessels  were  distended  with  it.  His  injections  were  finer 
than  Ruysch's,  and  he  filled  the  minutest  vessels  in  the  skin,  brain, 
and  capsule  of  the  lens.  The  latter,  however,  must  have  been  in  the 
foetus,  as  there  are  no  vessels  in  the  capsule  of  the  adult.  William 
Hunter,  who  examined  his  injections  in  1748,  was  deeply  impressed 
by  them.  In  1756  Albinus  is  combating  vigorously  Ruysch's 
doctrine  that  the  human  body  is  composed  entirely  of  vessels. 

Between  1721  and  1732,  when  Monro  primus  pubKshed  his 
first  paper  on  injections,  several  writers  deal  with  the  subject,  but 
little  is  added  to  what  was  already  known.  Helvetius  ^  supports 
Ruysch  in  holding  that  the  whole  body  is  almost  nothing  more 
than  a  prodigious  assemblage  of  lymphatic  and  blood  vessels,  but 
considers  that  injections  are  deceptive  in  attracting  too  much 
attention  to  the  blood-vessels.  The  latter  belief  finds  an  apt 
illustration  in  the  work  of  Stukeley  on  the  spleen,*  whose  injections 
of  wax  in  two  colours  induced  him  to  adopt  the  view  that  the 
spleen  consists  almost  entirely  of  the  ramifications  of  the  splenic 
artery.  He  admits  the  presence  of  a  few  muscular  fibres,  but 
even  the  veins,  according  to  this  author,  are  only  slightly  con- 
cerned with  the  internal  economy  of  the  gland.  According  to 
WiUiam  Hunter,  who  as  a  contemporary  might  be  expected  to 
know,  Nathanael  St.  Andre  (1680-1776)  was  one  of  the  earh' 
English  injectors,  and  Haller  asserts  that  St.  Andre  claimed  to 
have  injected  vessels  in  the  epidermis  with   quicksilver.     This 

1  Michael  Bernard  Valentin  (1657-1729),  Amphitheatmm  Zoolomicum,  Frank- 
furt, 1720,  fol. 

2  Bernard  Siegfried  Albinus  (1C97-1770),  Oratio,  qua  in  veram  nam,  quae  ad 
fabricae  humani  corporis  cognitionem  ducat,  Leyden,  1721,  4to.  Academicarum 
Annotationum,  Leyden,  1754,  Lib.  1,  4to. 

3  John  Claude  Adrian  Helvetius  (1685-1755),  Idee  ginerale  de  Voeconomie 
animale,  Paris,  1722,  8vo. 

*  William  Stukeley  (1687-1765),  OJ  the  Spleen,  its  description  and  History, 
London,  1723,  fol. 


322       rHK   niSTOKV  OF  ANATOMICAL  lN.JE(TiONS 

sinister  pliysiciaii  is  also  said  to  liavc  possessed  a  collection  ol 
anatomical  preparations,  but,  to  (luote  Hutchinson,  '  after  liis 
deceaNSO  Mr.  ('hristie's  auction  room  bore  abundant  witness  to  the 
frivolity  of  his  collections  '.  Nicolai  '  praises  isinglass  as  an  injec- 
tion medium,  but  finds  that  it  extra vasates  t(jo  rea(hly,  and  is 
apt  to  fill  cavities  and  leave  the  vessels  empty.  Isinglass  is  also 
recommended  by  Mauchart,'  who  again  is  the  first  to  experiment 
with  injections  of  plaster — previously  recommended  })y  Boyle. 
The  desire  to  imitate  Ruysch's  preparations,  and  the  difficulty  of 
doing  so  owing  to  a  lack  of  knowledge  of  his  procedure,  is  referred 
to  by  Wagstaffe,^  who  reproaches  Ruysch,  then  living,  for  con- 
cealing his  methods.  He  refers  to  the  futility  of  exhibiting  injec- 
tions as  a  mysterious  curiosity,  and  not  as  a  scientific  invention 
available  to  all  for  the  advancement  of  knowledge.  '  Dr.  Ruysch 
has  given  us  several  excellent  and  curious  drawings  of  the  finest 
preparations  in  the  world  ;  but  we  had  certainly  been  more 
obliged  to  him,  if  he  had  communicated  his  observations  on  the 
manner  of  preparing  them,  and  form'd  from  thence  a  noble,  a  just 
and  a  demonstrative  rationale  of  the  uses  of  the  parts.'  This  lack 
of  candour,  however,  continued  to  discredit  the  publications  of 
anatomists,  for  much  later,  in  1784,  Sheldon,  when  referring  to 
the  great  improvement  in  the  art  of  injection  '  in  late  years  ',  says 
that  '  progress  of  the  science  has  undoubtedly  been  much  impeded 
by  the  mystery  observed  among  anatomists,  respecting  the  com- 
[)Osition  of  their  injections,  and  their  method  of  dissecting,  injecting, 
and  preparing  the  different  parts  :  a  mystery  ^vhich  deserves  the 
severest  censure,  and  is  unworthy  of  the  character  of  a  philosopher 
or  a  man  '.  He  adds  :  '  I  shall  disclose,  without  reserve,  whatever 
I  am  acquainted  with  on  this  head.'  Jesse  Foot,  in  1794,^  praises 
Sheldon  for  '  his  unreserved  discovery  [disclosure]  of  the  art  of 
injecting  ',  and  endorses  his  disapproval  of  a  proprietary  anatomy. 
On  the  other  hand,  Drake,  in  a  posthumous  work,^  explains  and 

1  Henricus  Albertus  Nicolai  (1701-33),  De  directione  vasorum  pro  modifimndo 
sanguinis  circulo,  Strassburg,  1725,  4to. 

2  Burchard  David  Mauchart  (1696-1752),  Programma  Anatomicum  de  iniec- 
tionibus  sic  dictis  anatomicis,  Tubingen,  1726,  4to. 

3  William  Wagstaffe  (1685-1725),  In  Drake's  Anthropologia  Kova,  London, 
1727,  8vo,  ed.  3,  vol.  i,  p.  xi. 

4  Jesse  Foot  (1744-1826),  The  Life  of  John  Hunter,  London,  1794,  8vo. 

5  James  Drake  (1667-1707),  Anthropologia  Nova,  London,  1728,  8vo,  Appendix, 
Plate  51. 


I 


THE  HISTORY  OF  ANAT0M1(\\L  INJECTIONS     :i23 

figures  a  large  injecting  syringe  holding  twenty  ounces.  The  intake 
is  separate  from  the  outflow,  and  both  have  cocks  so  that  the 
sjrringe  can  be  refilled  without  removing  the  nozzle  from  the 
vessel,  as  first  practised  by  (\  Bartholin.  The  outflow  pipe  is 
a  flexible  one  of  leather,  and  the  nozzle  is  of  brass  or  silver,  and 
small  enough  to  '  pass  into  the  lacteal  vessels  and  chyhferous 
ducts  '.  Lancisi,^  by  syringe  injections  of  mercury,  coloured  water, 
and  air,  perpetuates  the  error  of  Vieussens,  Verheyen  and  others 
that  '  there  are  meanders,  wdnding  passages,  and  diverticula 
leading  from  the  coronary  veins  into  each  of  the  four  cavities  of 
the  heart,  and  that  the  blood  makes  use  of  these  as  outlets  '.  By 
means  of  these  '  outlets  '  Lancisi  believes  that  the  blood  '  alter- 
nately goes  in  and  out  with  a  kind  of  ebb  and  flow  '.  An  attempt 
at  histological  injection  was  made  in  1728  by  Price, ^  who  studied 
the  structure  of  the  villi  of  the  ox  and  filled  the  vessels  with  wax, 
but  no  results  of  interest  or  importance  accrued.  Weiss,^  improving 
on  the  practice  of  Ruysch,  adopts  a  method  which  w^as  almost  at 
once  developed  and  standardized  by  Monro  and  Cassebohm.  He 
injects  the  human  body  by  immersing  it  for  a  long  time  in  warm 
water,  and  then  throwing  in  first  coloured  turpentine  to  fill  the 
smaller  vessels,  and  afterwards  a  wax  medium  to  distend  and  seal 
the  larger  ones.  '  A  gross  mixture  of  wax,  tallow,  and  vermilion  ' 
is  used  by  Mortimer  ^  to  inject  the  arteries,  and  the  same  substance, 
but  coloured  with  smalt,  to  fill  the  veins.  This  is  one  of  the  few 
references  to  a  differential  injection  of  arteries  and  veins  since  the 
method  was  first  introduced  by  Duncan  in  1678.  A  general 
description  of  wax  injection  is  given  by  Thiesen,^  and  Trew  ^  is 
an  early  experimenter  with  fluid  plaster,  which,  however,  he  does 
not  consider  an  efficient  substitute  for  wax.     He  tried  also  the 

1  Giuseppe  Maria  Lancisi  (1654-1720),  De  motu  cordis,  Rome,  1728,  fol. 

2  Charles  Price,  '  Remarks  on  the  Villi  of  the  Stomack  of  Oxen,'  Phil.  Trans., 
London,  1728,  vol.  xxxv,  p.  532,  4to. 

3  Johannes  Nicolaus  Weiss  (1702-1783),  Theses  sistentes  viscerum  glandularum, 
Altdorf,  1729,  4to  ;  De  structura  venarum,  ibid.,  1733,  4to  ;  De  aquae  adminiculo 
in  adminisiratione  anatomica,  ibid.,  1733,  4to. 

*  Cromwell  Mortimer  (ob.  1752),  '  Case  of  some  uncommon  anastomoses  of 
the  spermatic  vessels  in  a  Woman',  Philosophical  Transactions,  London,  1730, 
vol.  xxxvi,  p.  373,  4to. 

5  Gottfried  Thiesen  (n.  1705),  De  materia  ceracea  eiusque  iniectione  anatomica, 
Konigsberg,  1731,  4to. 

*  Christopher  Jacob  Trew  (1695-1769),  Commercium  Litterarium,  Niirnberg, 
Spec.  9,  1731,  Hebd.  30,  1736,  4to. 


:j2i     rnK  msroKV  of  anatomical  iNJKcrnoN.s 

ve^ctablo  resins,  rcsiiia  aiiiiiK'  and  sandaracli,  and  isinglass,  and 
sliows  that  injected  incremy  passes  through  the  capillaries  and 
completes  the  circulation.  Vater  '  was  a  ])upil  of  Kiiysch,  and  was 
trained  in  injection  methods  by  him.  He  employed  different 
coloured  licpiids  and  wax,  and  according  to  Haller  was  most  skilled 
in  the  art  ol  filling  the  ves.sels,  producing  results  equal  to  those 
of  his  master.  The  short  paper  published  by  Monro  }>rimus  in 
1732  "  is  ifnportant,  not  on  account  of  its  originality,  but  because 
of  the  intluencc  it  exercised,  and  tiie  method  there  recommended 
was  very  widely  ado])ted,  and  is  not  even  now  entirely  abandoned. 
Monro's  article,  for  example,  forms  the  basis  of  the  chapter  on 
injection  by  Daubenton  in  Buflfon's  Hisloire  naturelle.  Monro 
says  :  '  Scarce  any  anatomical  books  describe  with  accuracy  the 
method  of  injecting,'  and  again,  '  few  have  hit  on  the  art  of 
injecting  the  very  small  capillary  tubes  '.  He  uses  a  brass  syringe 
which  includes  a  contrivance  for  re-filling  without  removing  the 
nozzle  from  the  vessel — as  previously  recommended  by  Bartholin 
and  Drake.  For  '  subtile  or  fine  injections  '  he  proceeds  as  follows  : 
Macerate  in  warm  water  to  liquefy  the  blood.  First  inject  coloured 
oil  of  turpentine  to  fill  the  very  small  vessels,  and  follow  up  at 
once  with  a  coarser  injection  to  distend  the  larger  ones.  The  two 
media  mingle  in  the  vessels,  so  that  it  is  impossible  to  tell  from 
inspection  that  two  have  been  used.  The  colours  employed  are 
vermihon  for  arteries  and  distilled  verdigris  for  veins — mixed  with 
clear  oil  of  turpentine  and  filtered  or  decanted  to  get  rid  of  the 
granules.  His  coarse  injection  is  composed  of  tallow,  one  pound, 
bleached  white  wax,  five  ounces,  and  salad  oil,  three  ounces.  Melt 
and  add  two  ounces  of  Venetian  turpentine.  Sprinkle  in  the 
colour  and  filter  through  a  linen  cloth.  Some,  if  not  most,  of  the 
Hunterian  preparations  in  the  Royal  College  of  Surgeons  must 
have  been  injected  by  this  method,  since  when  they  are  cut  or 
dissected  thej^  bleed  from  the  finer  vessels  only.  Two  years  later 
Monro  published  a  striking  but  neglected  paper  ^  in  which  the 
independence  of  the  maternal  and  foetal  bloods  in  the  placenta 

1  Abraham  Vater  (1684-1751),  De  iniectionis  variorum  colorum  utilitate  ad 
viscerum  structuram  detegendam,  Wittemberg,  1731,  4to. 

2  Alexander  Monro,  primus  (1697-1767),  '  An  Essay  on  the  Art  of  injecting 
the  vessels  of  animals  ',  Medical  Essays  and  Observations  published  by  a  Society  in 
Edinburgh,  Edinburgh,  1732,  vol.  i,  12mo. 

*  '  An  Essay  on  the  Nutrition  of  Foetuses',  Medical  Essays,  &c.,  Edinburgh, 
1734,  vol.  ii,  12mo.    Some  copies  are  dated  1733. 


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3 


THE  HISTORY  OF  ANATOMICAL  INJECTIONS     325 

is  for  the  first  time  placed  beyond  question  by  injection  exi)eri- 
ments.  On  this  occasion  he  makes  use  of  oil  of  turpentine  coloured 
with  vermilion,  and  mercury.     He  says  : 

'  The  liquors  are  not  carried  from  the  mother  to  the  foetus,  or 
from  the  foetus  to  the  mother  by  continued  canals,  that  is,  the 
uterine  arteries  and  veins  do  not  anastomose  with  the  veijis  and 
arteries  of  the  secundines  ;  but  the  extremities  of  the  umbilical 
vein  take  up  the  liquors  by  absorption  in  the  same  way  as  the 
lacteal  vessels  do  in  the  guts  ;  and  the  umbilical  arteries  pour 
their  liquors  into  the  large  cavities  of  the  sinuses,  or  other  cavities 
analogous  to  them.' 

It  should,  however,  be  pointed  out  that  in  Monro's  time,  to 
quote  his  own  words,  absorption  was  a  process  '  whereby  the  small 
ope