28 GRIESBACH : GEOLOGY OF THE CENTRAL HIMALAYAS. 



belt, flows onwards to join the Alaknanda at the foot of the Lower 



Himalayas. Its principal tributary, the J£dh Ganga, joins with many 



side streams from its right side. 



The Alaknanda is formed by the head-waters of the Dhauli and 



Vishnu-Gangas, which are separated by the 

 Alaknanda river. Kamet ^^ ^ .^ further progress through 



the hills the Alaknanda takes up a number of important tributaries, 

 finally uniting with the Bhagirathi before emerging from the lower 

 hills into the plains. 



West of the Bhagirathi flows the Jumna with its many tri- 

 butaries. The head-waters of this system rise 

 Jumna. ... r xt-i ■» 



amongst the great heights west of Nilang, and 



the streams which further on form the Jumna have eroded a deep 

 basin between the ranges which on one side divide it from the Bhagi- 

 rathi, and on the other from the Sutlej. 



West of the true Ganges branches is the drainage basin of the 



K£li, which forms the boundary between Ku- 



Kali river. , KT ^. ^ f ., . • ,«_ 



maun and Nepal. One or its sources is in the 



Byans pass, where 'it rises, as an insignificant stream, at the foot of a 



small glacier. But this is soon re-inforced by numerous glacier streams 



and important tributaries on both sides, so that it forms, further 



down, one of the largest contributions to the Ganges. Amongst 



the streams which join the Kali on its right side are the Kuti Yangti, 



the Dharma (with the Lissar) Ganga and the Gori Ganga. They all 



cut through the complicated folds of the sedimentary series which 



form the northern range of the Central Himalayas and often expose 



good sections. 



All these rivers are of great volume and possess strong currents > 

 as, for instance, the Kali river during a course of about 130 miles 

 descends 15,000 feet, or about 115 feet per mile. Most of them con- 

 stitute formidable obstacles to travelling in those high regions, and 

 even many of the minor streams are only fordable with difficulty and 

 often with considerable danger. 



A very large part of the Central Himalayas is situated above the 



( 28 > 



