170 POPULAR SCIENCE MONTHLY. 



cliffs, slopes and water courses, as we now distinguish the cotyledons, 

 stem, buds, leaves, flowers and fruit of a rapidly-maturing annual that 

 produces all these forms in appropriate order and position in the brief 

 course of a single summer. 



The time is ripe for the introduction of these ideas. The spirit of 

 evolution has . been breathed by the students of the generation now 

 mature all through their growing years and its application to all lines 

 of study is demanded. It is true that the acceptance of inorganic as 

 well as of organic evolution is often implied rather than outspoken; yet 

 evolution. is favorably regarded, as is proved by the eagerness with 

 which even school boards and school teachers, conservatives among 

 conservatives, hail the appearance of books in which the new spirit 

 of geography is revealed. In the last years of the century, the school 

 books most widely used in this country have made great advance in the 

 explanatory treatment of land forms. Tarr's Physical Geographies and 

 Russell's monographic volumes on the 'Lakes,' 'Glaciers,' 'Volcanoes' 

 and 'Rivers' of North America, all presenting land forms in an explana- 

 tory rather than an empirical manner, have been warmly welcomed in 

 this country. Penck's 'Morphologie der Erdoberflache' (1894), although 

 largely concerned with the historical development of the subject, pre- 

 sents all forms as the result of process. De Lapparent's 'Lemons de 

 geographie physique' (1886) treats land forms generically; and a 

 second edition of the book is called for soon after the first. 'Earth 

 Sculpture,' by James Geikie (1899), and Marr's 'Scientific Study of 

 Scenery' (1900), carry modern ideas to British readers. There can be 

 little doubt that the books of the coming century will extend the habit 

 of explanation even further than it has yet reached. 



This review of the advance of the century in the study of land 

 forms, the habitations of all the higher forms of life, might have been 

 concerned wholly with the concrete results of exploration, as was im- 

 plied in an earlier paragraph. Travels in the Far East of the Old 

 World, or in the Far West of the New, have yielded fact enough to fill 

 volumes. But such a view of the century has been here replaced by 

 another; not because the first is unimportant, for it is absolutely essen- 

 tial, but because the second includes the first and goes beyond it. Not 

 the facts alone, but the principles that the facts exemplify, demand our 

 attention. These principles, founded upon a multitude of observations, 

 are the greater contribution of the closing to the opening century in 

 the study of the Forms of the Land. 



