474 REVIEWS 



mies, and institutions of similar grade. The book was written in the 

 belief that it is the function of a text as well as the duty of a teacher to 

 develop in the student the power to reason. This spirit pervades the 

 work throughout. 



The method is essentially analytical and the text explanatory rather 

 than descriptive. Abundant use is made of questions which are ingen- 

 iously devised to guide the student's mental operations and to lead him 

 unconsciously through certain desired chains of reasoning. Many of 

 the questions are inserted in the text — a practice which makes the stu- 

 dent stop and think and, by causing him to tie his ideas together, inciden- 

 tally and unconsciously brings him to see the interrelation of the dif- 

 ferent geologic agents and processes. 



The treatment throughout indicates a continuous desire to prevent 

 the student from forming hard-and-fast conceptions of processes and 

 geologic features that are necessarily often variable. There is a 

 steady determination to compel the student to maintain a critical open 

 mind and at the same time to draw close distinctions in the use of 

 variable terms, as in the relative heights of hills and mountains and of 

 plains and plateaus. Sometimes, however, this most laudable endeavor 

 threatens to overstep itself and lumber up the text with hypercritical 

 qualifications. In an elementary textbook where space is severely 

 limited unessential discriminations crowd out more weighty matter, 

 while the student on his part may come to give too much thought to 

 precision in little things at the expense of a grasp of great things. But 

 this is only another item in the ever-present question of where to draw 

 the line. 



The text is clear, direct, and well written. In some cases, as in 

 chap, i, the opening paragraph is a bit wobbly, but when the initial 

 groping for just the right line is past and the topic is well under way, 

 the chain of ideas, like the language, flows evenly and gracefully along 

 without effort. 



Poise and balance characterize the treatment of facts and principles. 

 The essential features are treated clearly though concisely, and the 

 minor features are subordinated or left out where their omission does 

 not weaken the presentation of the main topics. Unessential facts have 

 been carefully pruned. Keen discrimination is apparent here. 



The departure of the authors from current practice in the arrange- 

 ment of material will be most conspicuously seen in the omission of 

 separate chapters on vulcanism and earthquakes. This was done 

 in the belief that volcanoes and especially earthquakes are exceptional 



