PHYSIOGRAPHIC PROBLEMS OF TO-DAY 631 



of its nomenclature. The chief contribution to the science of the 

 earth's surface demanded of the explorer of new lands is a careful 

 record of facts. When a journey becomes a reconnoissance, with 

 physiography as its leading feature, it is not only an advance into a 

 more or less unknown region, but an excursion into the realm of ideas 

 as well. It is during such explorations, when one's mind is stimulated 

 by new impressions, that hypotheses spring into existence with 

 greatest exuberance. While most of these springtime growths are 

 doomed to wither in the more intense heat of subsequent discussion, 

 their spontaneity, and the fact that the mind, when not oppressed 

 by a multitude of details, grasps significant facts almost by intuition, 

 make the suggestions of the explorer of peculiar value. 



The detailed work of physiographic surveys falls into two groups: 

 namely, the study of definite areas, and the investigation of specific 

 problems. In each of these related methods the desirability of record- 

 ing facts by graphic methods is apparent. The demand for accurate 

 maps as an aid to both areal physiography and the study of groups 

 of specific forms, or the functions of concrete processes, needs no 

 more than a word at this time. With the growth of physiography 

 the time has come when the work of the individual explorer, who 

 from force of circumstances endeavors to follow many of the paths 

 he finds leading into the unknown, is replaced to a large extent by 

 well-organized and well-equipped scientific expeditions. It is from 

 such systematically planned campaigns, in which the physiographer 

 and representatives of other sciences mutually aid each other, that 

 the greatest additions to man's knowledge of the earth's surface 

 are to be expected. The most extensive of the unexplored or but 

 little-known portions of the surface of the lithosphere, in which a 

 rich harvest awaits the properly equipped expedition, are the sea- 

 floor and the north and south polar regions. As is well known, splen- 

 did advances have been made in each of these fields, but, as seems 

 evident, much more remains to be accomplished. 



In the branch of physiography appropriately termed "oceano- 

 graphy" the problems in view are the contour of the sea-floor, or its 

 mountains and deeps, plains and plateaus, the manner in which each 

 inequality of surface came into existence, and the various ways it 

 is being modified. In both of these directions the interests of the 

 physiographer merge with those of the biologist and the geologist. 

 One phase of the study of the ocean's floor which demands recog- 

 nition is that the topographic forms there present are such as have 

 been produced almost entirely by constructional and diastrophic 

 agencies, free from complications due to erosion which so frequently 

 obscure the result of like agencies on the land. For an answer to the 

 question: What would have been the topography of land areas, 

 had there been no subaerial decay and denudation? the topography 



