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SCIENCE. 



[N. S. Vol. XIV. No. 345. 



cision and detail hitlierto unknown. It re- 

 fers them to their places in a genetic classi- 

 fication. It assigns them to their order in 

 an evolutionary life history. Furthermore, 

 it uses them as the older geology used fossils 

 and the succession of strata ; it reads in re- 

 liefs the story of the geological past. It 

 not only explains the present by the past, . 

 but it also reveals the past by means of the 

 present . The physiognomy of a region may 

 be the record of a large part of its geological 

 history. While the geomorphologist requires 

 the special equipment and competence of the 

 geologist, it is no less true that the geologist 

 must now perforce be a geomorphologist. 



In the geological courses now offered in 

 American universities land forms have a 

 large and increasing place. It is given 

 under different names, but with essentially 

 the same content. In some, as in the Uni- 

 versity of Wisconsin, applications to human 

 life are included, an essentially geographic 

 subject. In the higher American schools, 

 with one notable exception, Harvard, it is 

 only in the laboratories and lecture rooms 

 of the department of geology that the stu- 

 dent of land forms can obtain adequate 

 training. " The surest foundation," as Eich- 

 thofen has said, ' ^ for the study of geography 

 is geology, in its whole compass, as being 

 the only means to an understanding of the 

 earth's surface." Geology thus retains pos- 

 session of the field both in research and in 

 advanced instruction. 



As Davis has pointed out, land forms are 

 _ functions of three variables — structure, 

 process and time. The first of these, struc- 

 ture, together with the causes which have 

 produced it, is undoubtedly a geological 

 subject, and it is from geology that the 

 geomorphologist must here draw all his 

 data. Process has always been treated 

 under dynamic geology, and yet as a part 

 of geophysics, as treating of agents now in 

 action upon the earth, it belongs also to 

 geograph3^ The cycle of time, ' that un- 



measured part of eternity,' during which 

 process produces upon structure the evolv- 

 ing series of topographic forms may well be 

 claimed by the science which deals with the 

 past history of the earth. The position of 

 geologists is well stated by Sir Archibald 

 Geikie in answer to the argument of Sir 

 Clements Markham, President of the Eoyal 

 Geographic Society, who had drawn the 

 line between the two sciences at the dawn 

 of history, excluding geology from the study 

 of the changes of the earth's surface since 

 that time. " Since geology may be re- 

 garded as the history of the earth, whatever 

 is necessary for the elucidation of that his- 

 tory will be claimed by the geologists as 

 part of their domain. Only as they under- 

 stand what is going on at the present day 

 can they understand what took place in 

 past time. If you take away from the 

 geologist the study of all that is taking 

 place now, and maintain that this study is 

 not geology but physical geography, he 

 will answer, ' I do not care what you call 

 it. I must be at liberty to investigate the 

 processes which are operating now, in order 

 that I may be able to explain what has 

 happened in past time.' " 



The dependence of geography on geology 

 often has been compared with that of paint- 

 ing or sculpture upon anatomy. But the 

 simile is far from complete, unless the 

 former science is content to remain descrip- 

 tive only, dealing with the delineation of 

 external form. For the reliefs of the land 

 must be studied and classified not primarily 

 or chiefly as to form, but by structure and 

 genesis. So soon as the description of the 

 features of the earth's surface and their dis- 

 tribution yields to an inquiry into their 

 origin, the line is passed which divides the 

 -graphy from the -logy. 



These questions are not perhaps without 

 some practical outcome. The organization 

 of these sciences, and the theoretic limits 

 between them in the field of research in- 



