July 6, 1917] 



SCIENCE 



essity for transporting heavy artillery, for 

 whieli the ordinary road-bed is inadequate. 



Topographic maps carry a special meaning 

 for the trained geologist while geological 

 maps yield information of value in regard to 

 the strategic quality of the country of ad- 

 vance; even without maps the geologist can 

 draw inferences as to the ease and safety 

 with which the country ahead may be trav- 

 ersed. The vibration effects of prolonged 

 artillery fire in mountainous regions are 

 likely to cause landslides and snowslides, 

 which may prove disastrous if not anticipated 

 and guarded against; but vibrations arising 

 from the enemy's fire may be turned to ad- 

 vantage through seismographic records, 

 showing the point of origin. Lastly, the 

 question of an adequate water-supply is ever 

 present, and the ordinary sources may often 

 be enlarged or improved upon by the location 

 of imderground or artesian waters, while in 

 deserts the avoidance or chemical improve- 

 ment of waters too strongly alkaline becomes 

 frequently of paramount importance. 



In these respects, then, an army without 

 geological knowledge is at a disadvantage; 

 for the problems mentioned are all within the 

 capabilities of the geological engineer and 

 some of them must remain unsolved if geol- 

 ogical advice is not at hand. 



In the second place, an army employing 

 geologists in its field activities can facilitate 

 their effectiveness by maintaining a geological 

 department at home for the accumulation of 

 geological data and in particular of geologi- 

 cal maps covering all possible regions of mili- 

 tary activity. It is no small task to assemble 

 such material in form and quantity suitable 

 for use on short notice in any part of the 

 world. Such a department, therefore, 

 should be established in advance of field oper- 

 ations. A new type of map recently employed 

 by physiographers, which shows by a block 

 diagram both the topographic features and 

 the underlying rock structures, would with- 

 out question prove of distinct advantage to 

 commanding officers planning a campaign 

 or executing field manoeuvers. Few maps 

 of this kind have ever been constructed; 



their preparation is slow and requires consid- 

 erable skill and knowledge. It would fall 

 within the province of the home office to 

 develop the usefulness of this sort of map. 

 The department also would appropriately 

 assemble information on the water resources 

 oi regions of prospective occupation, so 

 that the geologist in the field might be sup- 

 plied with such results of previous geologic 

 work, particularly in the enemy's country, as 

 would facilitate his search for sources of 

 water-supply. 



A third way in which geology can contrib- 

 ute to the military strength of a country is 

 through a study from a military standpoint 

 of its mineral resources, the raw materials of 

 wax. In the United States, our mineral re- 

 sources have long been the subject of organ- 

 ized investigation on the part of the Geolog- 

 ical Survey, which has accumulated detailed 

 and accurate information regarding them of 

 the highest value at the present time. But 

 the investigations of the Geological Survey 

 have naturally been confined largely to the 

 economic and scientific aspects of its field, and 

 while much of its information can be quickly 

 interpreted in terms of military necessity, the 

 fact remains that this accumulated knowledge, 

 much of it of the deepest military significance, 

 has remained largely unused by military au- 

 thorities, and the United States to-day is un- 

 prepared in respect to a few mineral products 

 essential to war, such as nitrogen, potash, 

 manganese, nickel, tin, and platinum. This 

 country as a whole, however, is at a rel- 

 atively efficient stage of preparedness in re- 

 gard to her mineral industry, not because the 

 govenunent has studied and anticipated her 

 military needs in this respect, but because re- 

 cent economic demands have in most partic- 

 ulars been analogous to impending war de- 

 mands, and hence the mineral industry un- 

 der present economic conditions is largely on 

 a military footing. But this does not ob- 

 viate the desirability of a further military- 

 geological study of our mineral wealth, for 

 conditions are ever changing and we should 

 anticipate every eventuality. In the futiu-e, 

 the military importance of minerals is bound 



