112 Dr. Verchere on the Geology of Kashmir, [No. 2, 



began to deposit a sediment which, in time, formed the great flat 

 plateau of Thibet, Rodok, Aksai Chin, &c. &c. Thus we see the 

 altered physical conditions which were brought about by the difference 

 of elevation of the Himalaya, before and after its final upheaval. 

 Before the upheaval, the humidity was collected as rain, and the 

 mountain debris was washed to the coast by boisterous torrents ; but 

 after the upheaval, the humidity was collected as snow, and the 

 mountain debris was quietly collected in the great valleys, under the 

 cover of glaciers.* 



All the while, a different action was going on in the outer or low 

 Sub-Himalayan ranges. There the humidity continued to fall as rain 

 and great denudation was the result. The same process of land 

 gaining over the sea, which I have described at the Miocene epoch, 

 began to form the plains of India ; this process is still in operation 

 now-a-days, but necessarily its power diminishes in intensity as the 

 sea-coast becomes more distant from the hills and the course of rivers 

 becomes longer. It is the process which is now anxiously watched 

 by the pilots of the Hooghly, and which no engineering skill can 

 avert : the sandbanks advance in the sea, the river-bed fills up, more 

 dry land appears and what was yesterday a dangerous shallow out at 

 sea, to-day is the shore of the delta, and to-morrow will be far inland. 



As the plains of India extended, the rain-fall of the Himalaya 

 diminished. Even if we suppose the humidity of the winds to have 

 been the same as before, we must deduct from the Himalayan rain-fall 

 the amount of rain which fell in the plains. But we know that the 

 humidity of the rains had also become less ; the Ancles had surged 

 up and the South- American continent had appeared ; the plains of 

 Africa, Arabia, Persia and Central Asia were gradually appearing 

 above the waters, and instead of the trade winds, the monsoons were 

 establishing themselves. There was therefore a great diminution in the 

 snow-fall on the Himalayas, and the glaciers began to decrease and to 

 expose a great deal of the plateau on which they had gradually raised 

 themselves. It is easy to understand how this decrease of snow-fall 



* The filling up of the great parallel valleys of the Himalayas by 

 mud and boulders, under the cover of the glaciei'S, is analogous to the filling 

 up of depressions of the surface by the glacial drift in some parts of Europe. 

 The glaciers of the Himalaya, soon after the great upheaval, were too huge and 

 too general to have had a ploughing and scouring action on the valleys. 



