Jan., 11)17] The Future For Geologists 93 



many deposits arc yet to be found. It is reasonably safe, 

 however, to estimate that the known problems and occurrences 

 will keei^ the geologist busy for some generations. 



All these problems relating to the genesis of mineral, rock 

 and ore deposits, those relating to the nature, and change of 

 nature, of the earth's interior, those of vulcanism, seismology, 

 and diastrophism, of stratigraphic interpretation, and of the 

 paleontologic record run back to the question of the origin of 

 the earth. The latter cannot be considered solved until these 

 are worked out. But I prefer to postpone cosmic geology a 

 moment for two other considerations. 



9. In the field of Physiography or Physiographic Geology, 

 as it is known by some investigators, the detailed mapping 

 cannot well precede the topographic mapping discussed near 

 the beginning of this paper. It was shown there that several 

 generations will yet find employment before the topographic 

 map of the world is done, unless our pace be greatly accelerated. 

 Hence physiographic mapping w411 be equally delayed. But 

 more can be said. Physiographic mapping not only cannot 

 precede topographic w^ork; it does not to date nearly keep up 

 with the latter. Really but very limited and disconnected 

 areas have been mapped and interpreted from the physio- 

 graphic viewpoint. True, these are usually at more or less 

 critical or typical places as New York City and Watkins Glen 

 quadrangles, Tacoma quadrangle, Mooers, N. Y., Columbus, 

 Ohio, Chicago, and Niagara, in America, and similarly restricted 

 areas in Europe. Much excellent topical w^ork has been done, 

 as the Lake surveys of Scotland, Glacial features of the lobes 

 of the Great Lakes and Prairie region of the United States, the 

 studies of the Lake Plains in Northern Ohio, and others. But 

 here again the problems that may be studied as topics are so 

 numerous that one hardly knows which way to turn or where to 

 begin. These studies already undertaken have led to many 

 generalizations, but imperfections in some of these will undoubt- 

 edly stand out boldly as other similar or related areas are 

 studied. Very little is known yet of the physiography, even 

 descriptively, to say nothing of interpretation, in the portions 

 of the earth in arid climates; and yet arid climates prevail over 

 some 10,000,000 square miles, or one-fifth of the land area 

 of the world. Nor do we know much as yet of the topography of 

 the ocean floor. 



