174 W. CROSS GEOLOGY IX THE ^\'ORLD WAR AND AFTER 



of the enemies' weaknesses in the respects under consideration has a great 

 advantage, which may well become decisive in certain areas. 



Man}^ accounts of conditions at the front give vivid descriptions of the 

 fearfully destructive effect of modern explosives on the ground of the 

 battle zone, especially of the terrific barrage fire from heavy guns. Such 

 bombardment is undertaken at different times for different reasons. Its 

 most destructive results in certain areas, arising from the local nature of 

 the rocks, may be entirely aside from the main objective. But let us 

 suppose that the geological experts of one army have made a special study 

 of the enemies' position with regard to the rock formations, not only at the 

 front, but for miles in the rear, including his communication lines and 

 supporting works of all kinds, and that this special knowledge is used to 

 direct destructive gun fire on points weakened as a result of a period of 

 heavy rain. Can there be any doubt as to the superior effect of this fire 

 over that from an equal bombardment at random ? 



The work of the geologist with the army has many phases not yet 

 touched on which may be briefly reviewed. The process of mining is one 

 of the oldest methods of attack on fortified positions. A knowledge of 

 the rocks and ground to be encountered in a given project is manifestly 

 of great importance. Ignorance of such conditions has been responsible 

 for the total failure of many projects, even in this war: but perhaps the 

 largest operation of this kind ever attempted in any war, namely, the 

 destruction of the key position of Messines Ridge, was successfully planned 

 by geologists of the British army. 



The geological corps of an army engaged in position warfare is natu- 

 rally called on for reports on many special subjects, with profile sections 

 and maps in certain cases. These reports represent the adaptation of exist- 

 ing data to particular problems, such as maps of underground water re- 

 sources and the distribution of formations specially classified on military 

 grounds. This type of work may involve resurvey of some areas, as exist- 

 ing maps must in many cases prove inadequate in scale or accuracy. 



The geologist can and does adapt the information of geological maps 

 to a variety of special purposes; but the officer who can not read maps 

 can not use them efficiently and very probably can not comprehend their 

 importance. 



One of the lines in which the geologist's advice is or should be sought 

 is in regard to proper sites for camps, flying fields and hangars, artillery 

 emplacements, ammunition dumps, and other storage places, communica- 

 tion lines, etcetera, the object being to decrease so far as possible the 

 dangers and difficulties to which reference has been made. 



The value for war purposes of a thorough study of a peculiar terrain 



