ANNOTATIONS AND ADDITIONS. 89 



the sacred Lakes Manasa and Ravanahrada (at an elevation of 2345 

 toises, 14,995 English feet), in the vicinity of which the great river 

 rises, to Iskardo and to the plateau of Deo-tsuh (at an elevation of 

 2032 toises, 12,993 English feet), measured , by Vigne, follows in 

 the Thibetian highlands the same north-westerly direction as the 

 Himalaya. Here is the summit of the Djawahir, long since well 

 measured and known to be 4027 toises (25,750 English feet) in 

 elevation, and the valley of Kashmeer, where,, at an elevation of only 

 836 toises (5346 English feet), the Wulur Lake freezes every winter, 

 and, from the perpetual calm, no wave ever curls its surface. 



Having thus described the four great mountain systems of Asia, 

 which in their normal geognostic character are chains coinciding with 

 parallels of latitude, I have next to speak of the series of elevations 

 coinciding nearly with meridians (or, more precisely, having a SSE.- 

 NNW. direction), which, from Cape Comorin opposite to the Island 

 of Ceylon to the Icy Sea, alternate between the meridians of 66 

 and 77 E. long, from Greenwich. To this system, of which the 

 alternations remind us si faults in veins, belong the Ghauts, the Soli- 

 man chain, the Paralasa, the Bolor, and the Ural. The interrup- 

 tions of the series of elevations are so arranged that, beside their 

 alternate position in respect to longitude, each new chain begins in 

 a degree of latitude to which the preceding chain had not quite 

 reached. The importance which the Greeks (although probably not 

 before the second century) attached to these chains induced Agatho- 

 demon and Ptolemy (tab. vii. and viii.) to represent to themselves 

 the Bolor, under the name of Imaus, as an axis of elevation extend- 

 ing as far as 62 N. lat. into the low basin of the Lower Irtisch and 

 the Obi. (Asie Centrale, t. i. pp.138, 154, and 198 ; t. ii. p. 367.) 

 -As the perpendicular elevation of mountain summits above the 

 level of the sea (unimportant as in the eyes of the geologist the 

 circumstance of the greater or less corrugation of the crust of the 

 earth may be), is still, like all that is difficult of attainment, an object 

 of popular curiosity, the following historical natice of the gradual 

 progress of hypsometric knowledge may here find a suitable place. 

 When I returned to Europe in 1804, after a four years' absence, 

 not a single Asiatic snowy summit either m the Himalaya, the 

 Hindu-Coosh, or the Caucasus, had been measured with any exact- 



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