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Leitz Petrographical Microscopes
NEW MODELS-WITH ENLARGED FIELD OF VIEW
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A Source Book for the
of North America
By CHARLES C. COLBY
A i tilt ant Professor of Geography, the University of Chicago
The fundamental idea of the hook is to make
available to the busy teacher the material on this
subject which is scattered widely through litera
ture The course which has been given for a
number of years at the University of Chicago
has resulted in the collection and organization of
the material most suitable for the purpose
The book contain short magazine articles
and materials from Can dian, Mexican, and
United States government publications. The
selection of the material has been governed by
the concept that there is a dire t relation be
tween the environment and the economic activ
ities of the region The author aims to survey
the different section of the country from the
viewpoint of industrial opportunity
8vo, cloth; 400 pages, $4 00, postpaid $4 20
The University of Chicago Press
Chicago - - - Illinois
The Geography of Illinois
By DOUGLAS C. RIDGLEY
Professor of Geography in the Illinois State Normal University
The author's aim is to provide an authoritative study of the state, presenting in
compact form the wide range of physical influences which make up the geographic
environment in which men live.
The natural features and natural resources of the state are treated in some detail .
The great occupations of mankind — agriculture, mining, manufacturing, trans-
portation, and trade — are discussed with sufficient fulness to give an adequate
idea of their development and present importance within the state. The popula-
tion census of 1920 for Illinois is treated in a final chapter. The book is designed
to be of interest to the busy citizen who wishes to know his state as a unit in its
present-day activities; to teachers and pupils who would know Illinois well enough
to interpret other regions in comparison with the home state; to all who wish to
learn the reasons for the high rank of Illinois in many lines of human endeavor.
Abounds with draw'ngs, maps, illustrations, and colored insert maps
xviii+385 pages, i6mo, cloth; $2.50, postpaid $2.65
THE UNIVERSITY OF