160 SUB-HIMALAYAN ROCKS OF N. W. INDIA. [CHAP. VI. 



Chapter VI. — General discussion of the structure of the 

 hill ranges. 



The Himalayas, from several points of view, have formed the subject 

 of many scientific speculations. The only general discussion of them, 



however, based upon geological observations, with 

 Colonel Strachey's views 



on the structure and his- which I am acquainted, is that by Colonel R. 

 tory of the Himalayas. 



Strachey, published in two papers in the Quar. 



Jour. Geol. Soc, Lond., Vols. VII. and X., 1851 and 1854. It is deeply to be 

 regretted that this accomplished observer has not leisure or opportunity 

 fully to work out the abundant materials he has accumulated ; he could, 

 no doubt, give a much more complete account than is contained in his 

 brief papers to which alone I can refer. Colonel Strachey boldly at- 

 tempts a general sketch of the physical history of the Himalayas, fully 

 aware, no doubt, of how precarious and speculative such an attempt 

 must be upon data so incommensurable with the magnitude of the 

 problem. In this case, howewr, it is somewhat justifiable on the grounds 

 that except this attempt were made, the large mass of facts, which was 

 growing so unwieldy with the accumulated observations of many years, 

 would remain as so much dry detail, unprofitable to the interests of 

 general physical science. Premising the well-established fact that great 

 areas of the earth's crust have undergone actual upheaval, Colonel 

 Strachey states his conviction that the Himalayan mountain mass was 

 so upheaved. He then calls attention to a series of facts, from which 

 he draws conclusions as to the extent, amount, direction, and duration of 

 that upheaval. Most of the observations upon which his views are based 

 were made outside the region described in the foregoing Chapters ; it 

 will be necessary briefly to notice them. The region to which Colonel 

 Strachey's observations more particularly refer is that of Naini Tal and 

 Niti, in Kumaon. He describes the double fringing zone of younger 



