746 



SCIENCE 



[N. S. Vol. XXXII. No. 830 



Next indicate the commoner erosion 

 processes by Arabic numerals: 



surface water 1 



ice 2 



T^'^ocess^ ^.^^ 3 



sea 4 



One process may have followed another, 

 e. g., where a long period of ice erosion has 

 been followed by water erosion we might 

 write 21 where these alternate annually, 

 say 2.1. 



The phase of the cycle might be denoted 

 by Roman figures. A scale of V. might be 

 adopted and I., III. and V. used for youth- 

 ful, middle-aged and old-aged, as Professor 

 Davis calls them ; or early, middle and late 

 phases, as I shall prefer to term them. II. 

 and IV. would denote intermediate stages. 



A scarped limestone ridge in a relatively 

 mature phase like the Cotswolds would be 

 — ^if we put the process first — 1 C^ III. ; a 

 highland like the southern Uplands of 

 Scotland would be denoted by the formula 

 1. 2.1 W III. 



This is the roughest suggestion, but it 

 shows how we could label our cases of 

 notes, and pigeon-hole our types of forms 

 — and prevent for the present undue quar- 

 relling over terms. No doubt there would 

 be many discussions about the exact phase 

 of the cycle, for example, whether ice in 

 addition to water has been an agent in 

 shaping this or that form. But, after all, 

 these discussions would be more profitable 

 than quarrels as to which descriptive term, 

 or place name, or local usage should be 

 adopted to distinguish it. 



In the case of climatology, there is com- 

 ing to be a general consensus of opinion 

 as to what are the chief natural divisions, 

 and the use of figures and letters to indi- 

 cate them has been followed by several 

 authors. This should also be attempted for 

 oceanography. 



If any international agreement of sym- 

 bols and colors could be come to for such 

 things it would be a great gain, and I hope 

 to bring this matter before the next inter- 

 national geographical congress. 



We have still to come to geography itself. 

 What are the units smaller than the whole 

 earth with which our science has to deal? 

 When we fix our attention on parts of the 

 earth, and ask what is a natural unit, we 

 are hampered by preconceptions. We 

 recognize species, or genera, families or 

 races as units — but they are abstract 

 rather than concrete units. Speaking for 

 myself, I shovild say that every visible con- 

 crete natural unit on the earth's surface 

 consisting of more than one organic indi- 

 vidual is a geograiDhical unit. It is a com- 

 mon difficulty not to be able to see the 

 wood for the trees ; it is still more difficult 

 to recognize that the wood consists of more 

 than trees, that it is a complex of trees and 

 other vegetation, fixed to a definite part of 

 the solid earth and bathed in air. 



The family, the species and the race are 

 abstract ideas. If we consider them as 

 units, it is because they have a certain his- 

 torical continuity. They have not an ac- 

 tual physical continuity as the component 

 parts of an individual have. Concrete 

 physical continuity is what differentiates 

 the geographical unit. We may speak of a 

 town or state as composed of people, but a 

 complete conception of either must include 

 the spacial connections which unite its 

 parts. A town is not merely an associa- 

 tion of individuals, nor is it simply a piece 

 of land covered with streets and buildings ; 

 it is a combination of both. 



In determining the greater geographical 

 units, man need not be taken into account. 

 We are too much influenced by the mobil- 

 ity of man, by his power to pass from one 

 region to another, and we are apt to forget 

 that his influence on his environment is 



