Snow-Line in the Himalaya. 343 



elevation on the northern than on the southern face of the 

 chain.* 



The height to which the snow-line has been shewn to re- 

 cede on the southern face of the Himalaya, though consider- 

 ably gi'eater than had been supposed by M. Humboldt, still 

 does not exceed what the analogy of mountains in similar 

 latitudes in the other hemisphere might have led us to ex- 

 pect. In the Central part of Chili, in lat. 33° S., we find 

 that the lower limit of perpetual snow is at 14,500 or 15,000 

 feet, while in Bolivia, in lat. 18° S., it reaches 16,000, and 

 even on some of the peaks 19,600 feet.f There is therefore 

 no appearance of any thing unusual in the general height of 

 the snow-line, which need induce us to suppose the existence 

 of any extraordinary ascending current of heated air, regard- 

 ing which M. Humboldt enquires. The exceedingly high tem- 

 peratm-e, surpassing that known at any other pai't of the 

 earth's surface, which the air over the plains of North 

 Western India acquires during the summer, must of course 

 produce a sensible effect in heating the upper strata of the 

 atmosphere. But as far as I am enabled to form an opinion 

 from the few facts that have come to my knowledge, regard- 

 ing the temperature of the higher regions in these mountains, 

 I think there is little doubt that the same cause which pro- 

 duces this gTeat temperature in the plain, that is, the dii'ect 



•* The word " Himalaya," which, to the natives of these mountains, means 

 only the snowy peaks, is in the language of science applied to the whole chain, 

 and in my opinion properly. Any division of the chain into " Himalaya" or 

 snowy ranges, and " sub-Himalaya" ranges not snowy, such as has, I believe, 

 been made, appears to me objectionable, not only as unusual in the terminology 

 of physical geography, and therefore likely to lead to confusion, such as that 

 of which we have just had a specimen, but as artificial and unnecessary ; I re- 

 peat artificial, for, in spite of the specious appearance of the distinction, it will 

 not bear examination. The association of mountains into chains should be 

 based upon the physical character and affinities of the mountains themselves, 

 quite irrespective of any adventitious circumstances of snow, or of vegetable 

 and animal life. Botanical or zoological regions will almost always be found 

 to follow closely the configurations of the earth's surface, on the accidents of 

 which they chiefly depend ; but to make the classification of the latter depend 

 upon the former would be a manifest absurdity. 



t Asie Ceutralo, T. iii., pp. 270, 277, 32'J. 



