Reviews 



Geology Physical and Historical. By H. F. Cleland, Ph.D. 

 New York: American Book Co., 1916. Pp. 718, figs. 588. 



This new textbook enters the field of general geology, a field already 

 fairly well covered by a number of excellent books. The value of this 

 new attempt will depend upon new material, new methods of treatment, 

 or fewer infelicities than the other books have. The book occupies in its 

 scope a middle ground among the books on the subject, being more 

 ambitious than some and more modest than others. It will be used 

 properly as a textbook in first courses in general geology in colleges and 

 universities, where the students are at least fairly well prepared and 

 somewhat mature. 



The book is about the proper length best to serve its purpose, is 

 pleasingly written, beautifully illustrated, and well bound. The press- 

 work is exceptionally good. The reviewer has read the book through 

 and knows of but one typographic error. The book is printed on glossy 

 paper, and yet it is portable and durable. 



The author of the book seems to be more at home in Part II, "His- 

 torical Geology," than in Part I, dealing with physical geology. This 

 greater familiarity with the last portion of his subject is reflected in 

 better English, more careful treatment, more detail, and greater accuracy 

 and definiteness in Part II than in Part I. The best part of the book is 

 that dealing with life, although some will think that this phase of geology 

 is overdone. 



There are a few glaring omissions. The origin of dolomite is avoided 

 on p. 249. There is a chapter on earthquakes, but no presentation of 

 the more important aspects of diastrophism, except as the subject is 

 scattered through the chapters on structural geology, metamorphism, and 

 mountains and plateaus. This is a weakness which is felt throughout 

 the book. Proterozoic glaciation in Ontario, the causes of Permian 

 glaciation, the Pleistocene Driftless Area, are not mentioned. There 

 is no classification of the plant and animal kingdoms, an omission which 

 depreciates the value of the excellent paleontological material in Part II. 



With the exception of a few errors, such as plural nouns with singular 

 verbs or vice versa, indefinite antecedents of pronouns, a rather free 



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