1865.] Notes on Central Asia. 131 



snows with the exception of two patches, are only sporadic, and the 

 snow-line is not below 9,500 feet. This case proves that the snow- 

 line rises rapidly from the Altai to the Tarbagatai, owing to the 

 greater dryness of a continental atmosphere. Lastly, the barometrical 

 observations of Schrenck, in the Djungarian Alatau,in Lat. 45° N., fixed 

 the limits of eternal snows at 10.700 feet. Calculating then the height 

 of the snow-line in the Tian-Shan by a comparison of that of the 

 northern slope of the Himalayan, and of the Tarbagatai ranges, we 

 obtain 11,700 feet and 11,950 feet, if we take in the Djungarian 

 Alatau. 



In this manner all the facts of the case, not alone those supplied us 

 by comparative geography and climatology, but likewise those derived 

 from the exact observations of other travellers, tend to confirm my 

 figures, and prove them to be rather understated than magnified ; 

 Humboldt's doubts therefore as to the possibility of the snow-line of 

 the Tian-Shan exceeding 11,000 feet elevation, are disposed of not only 

 on theoretical considerations, but also by ocular demonstration. The 

 interesting questions relating to the existence of fine alpine glaciers 

 in the Tian-Shan, which is in intimate connection with that of the 

 height of the snow-line, I solved in complete accordance with the 

 previously expressed opinions of Humboldt and Bitter. I set out 

 without any foregone conclusions on this point, but having experienced 

 the remarkable dryness of the air in the Tian-Shan mountains, and 

 having ascertained, on ascending the Fauku Davan, that the height of 

 the snow-line was higher than 11,000 feet, involuntary doubts entered 

 my mind as to the possibility of the existence of real glaciers in the 

 Tian-Shan. These doubts were, however, soon dispelled. At the 

 sources of the river system of the Sary-Djaza, I came across five 

 magnificent alpine glaciers and a " Mer de glace" exceeding in size that 

 of Chamounix. Notwithstanding some of the peculiarities of the 

 Tian-Shan glaciers, owing principally to their prevalence at not more 

 than about 2,500 feet below the limit of the snow-line, while in 

 Switzerland they descend as low as 5,000 feet, their existence in the 

 form anticipated by Hitter and Humboldt, on the strength of Chinese 

 accounts, was fully confirmed. 



It now remained for me to prove, by actual observation on the spot, 

 the existence or otherwise of volcanic phenomena in Djungaria, and 



