NOVEMBEB 25, 1910] 



SCIENCE 



745 



tion, geography and economics for ques- 

 tions of transportation, etc. 



So much, then, for the classification of 

 geography with reference to the other 

 sciences. I should like to say a few words 

 about geographical classification and geo- 

 graphical terminology. 



In the scheme of the universe it is pos- 

 sible to consider the earth as a unit, with its 

 own constitution and history. It has an 

 individuality of its own, though for the 

 astronomer it is only one example of a 

 particular tjTpe of heavenly bodies. As 

 geographers we take it as our unit indi- 

 vidual in the same way that an anatomist 

 takes a man. We see that it is composed 

 of different parts and we try to discover 

 what these are, of what they are composed, 

 what their function is, what has been their 

 history. 



The fundamental division is into land, 

 water and air. Each has its forms and 

 its movements. The forms are more ob- 

 vious and persistent in the land. They are 

 least so in the atmosphere, though forms 

 exist — some of which are at times made 

 \'isible by clouds, and many can be clearly 

 discerned on isobaric charts. The land is 

 the temporarily permanent; the water and 

 atmosphere the persistently mobile; the 

 latter more so than the former. The stable 

 forms of the land help to control the dis- 

 tribution and movements of the waters and 

 to a less extent those of the atmosphere. 

 How great the influence of the distribution 

 of land and water is on the atmosphere 

 may be seen in the monsoon region of 

 eastern Asia. 



We can analyze and classify the subdi- 

 vision of the land, the water, and the atmo- 

 sphere. Each has given rise to a special 

 branch of study. 



Geomorphology deals with the forms of 

 the land and their shaping — geomorph- 

 ology, oceanography and climatolog}\ 



Three things have to be kept clearly in 

 view: (i) the structure, including the 

 composition, of the more permanent sub- 

 stance of the form; (ii) the forces which 

 are modifying it; and (iii) the phase in 

 the cycle of forms characteristic of such 

 structure acted on by such forms. We may 

 say that any form is a function of struc- 

 ture, process and time. The matter is 

 even more complicated, for we have in- 

 stances, e. g., in antecedent drainage sys- 

 tems, of the conditions of a previous cycle 

 afi'ecting a subsequent one — a kind of 

 heredity of forms which can not be 

 neglected. 



The geomorphologist is seeking for a 

 genetic classification of forms, and in the 

 works of Davis, Penck, Richtofen and Su- 

 pan and their pupils are being accumu- 

 lated the materials for a more complete 

 and systematic classification of forms. As 

 you all know, the question of terms for the 

 manifold land-forms is a difficult one and 

 apt to engender much more controversy 

 than the analysis of the forms themselves. 

 I have long thought that we shall be 

 driven to some notation analogous to that 

 of the chemists. I have not yet had time to 

 work such a notation out in detail, but it 

 might take the form of using different 

 symbols for the three factors noted above 

 — say, letters for different kinds of struc- 

 ture, and, say, Arabic figures for processes, 

 and Roman figures for the stage of a cycle 

 the form has reached. 



Take a very simple set of structures and 

 indicate each by a letter : 



r homogeneous 



f horizontal 

 \ la 



A A' 



B B' 



hiyered-l tilted C C 



^ folded D r>' 



L mixed K E' 



If per^aous or impervious, a p or an i 

 could be added — e. g., a tilted limestone 

 with faults would be C'p. 



