HEIGHT OF THE SNOW-LINE. 175 



tains also which enclose the dell of the Tagla are between 

 19,000 and 20,000 feet high, and just tipped with snow. 



The ditierence of height of the perpetual snows on the 

 northern and southern sides of the Himmaleh mountains is 

 further shown by the following remarks of Captain Gerrard. 

 Zamsiri, a halting-place for travellers on the banks of the 

 Shelti, is 15,600 feet above the sea, — a height equal to that 

 of the passes through the outer range of the Snowy Moun- 

 tains ; and yet, he says, there is nothing to remind the 

 traveller of the Himmalehs. Gently sloping hills and tran- 

 quil rivulets with banks of turf and pebbly beds, flocks of 

 pigeons and herds of deer, present the idea of a much lower 

 elevation. But nature has adapted the vegetation to the 

 country ; for did it extend no higher than on the southern 

 face of the Himmalehs, Tartary would be uninhabitable 

 either by man or beast. On ascending the southern acclivity 

 of the snowy range, the extreme height of cultivation is 

 found 10,000 feet ; and even there the crops are frequently 

 cut green. The highest habitation is 9500 feet ; 1 1,800 feet 

 may be reckoned the upper lunit of forests, and 12,000 that 

 of bushes, although, in a few sheltered situations, dwarf- 

 birches and small bushes are found almost at 13,000 feet. 

 But if we go to the Baspa river, the highest village will be 

 found at an elevation of 11,400 feet, cultivation reaching to 

 the same altitude, and forests extending to 13,000 feet at 

 least. Advancing farther, we find-villages at the last-men- 

 tioned elevation, cultivation 600 feet higher, fine birches at 

 14,000 feet, and tama bushes, which furnish excellent fire- 

 wood, at 17,000 feet. Eastward, towards Manasawara, 

 according to the accounts of the Tartars, crops and bushes 

 thrive at a still greater height. 



These facts, then, show not only that the snow-line gen- 

 erally is higher than was anticipated, but also that we must 

 ascend several thousand feet more on the northern than 

 the southern acclivity of this alpine land before we reach 

 the perpetual snow. Many explanations have been given 

 of this striking fact which we cannot discuss here. It is 

 sufficient to remark, that the radiation from the surface of 

 the table-land of Thibet, the dryness of the air throughout 

 "Central and Northern Asia, the small quantity of snow 

 which falls during winter when the temperature sinks to 

 10°4 F. or + 53 F., lastly, the serenity and transparency of 



