Studies in Minor Folds 



By CHARLES E. DECKER 



The author's purpose is to illustrate by diagrams 

 and photographs a series of types of minor folds; 

 to illustrate and study briefly a few minor folds in 

 their relation to major ones; to illustrate a larger 

 number of small folds in the midst of horizontal 

 or gently dipping strata, showing their character- 

 istics, methods of origin, age, and relation to 

 faults; and finally, to connect these minor 

 deformations, in so far as possible, with larger 

 movements, and show their significance, as 

 indicating the presence of compressional stresses 

 in the rocks in the interim between the great 

 periods of deformation and mountain-building. 



The data on which these studies are based have 

 been secured from a narrow area south of Lake 

 Erie, extending from Cleveland across north- 

 eastern Ohio, northwestern Pennsylvania, and 

 into New York as far as Dunkirk. A few folds 

 on Lake Ontario were studied, both in northern 

 New York and southern Canada. A few folds 

 were studied in the folded areas of the Arbuckle 

 and the Wichita Mountains of Oklahoma. 



Clotk; $1.50, postpaid $1.60 



The University of Chicago Press 



Chicago - - - Illinois 



Rhus Dermatitis 



Its Pathology and Chemotherapy 

 By JAMES B. McNAIR 



*l The lack of any rational treatment for 

 the common infection resulting from 

 poison oak or poison ivy has suggested 

 a protracted study of the isolated prin- 

 ciple, in the hope that knowledge of its 

 characteristic properties may serve as a 

 basis for such treatment, 



^ Complete analysis of cause, effect, and 

 remedy has been attained by investi- 

 gating from the three distinct standpoints 

 of pharmacology, botany, and chemistry. 



$4.00, postpaid $4.15 



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, manufacturmg, 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 m 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 drawings, maps, illustrations, and colored insert maps 

 3S5 pages, cloth, $2.50, postpaid $2.60 



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CHICAGO 



UNIVERSITY OF CHICAGO PRESS 



ILLINOIS 



i 



