334 Attempt to determine the mean helffht of Continents. 



Kouen-Lun). Mr Vigne's travels in Baltistan, which have just 

 appeared, the journal of the brothers Gerard, published by 

 Lloyd, as well as the recent investigations undertaken in India 

 respecting the relative height of perpetual snow on the Indian 

 and Thibetian declivities of the Himalaya, have demonstrated 

 that the mean height of the Thibetian plateaux has hitherto 

 been greatly exaggerated. In his work entitled " Central 

 Asia," of which only a few pages of the third volume have 

 been yet printed, and which will be accompanied by a hypso- 

 metrical map of Asia from the Phasis, as far as the gulf of 

 Petcheli, and from the common embouchures of the Ob and 

 the Irtysch to the parallel of Delhi, M. de Humboldt thinks 

 that he has demonstrated, by bringing together a multitude 

 of facts, that the prominence between the Himalaya and the 

 Kouen-Lun (chains which form the southern and northern 

 limits of Thibet), does not rise above the mean height of 1800 

 toises, and that it is, consequently, 200 toises lower than the 

 plateau of Lake Titicaca. 



The hypsometrical configuration of the Asiatic continent 

 is perhaps still more remarkable for its plains and depres- 

 sions, than for its colossal heights. This continent is distin- 

 guished by two principal characteristic features ; 1st, by the 

 long series of meridian chains, which, with parallel axes, 

 but alternating with each other (having perhaps been pro- 

 jected comme desjiloiif) extend from Lake Comorin, opposite 

 Ceylon, to the shores of the ley Sea, in a uniform direction 

 from south-south-east to north-north-west, under the name of 

 Ghates, the Soliman chain, Paralasa, Bolor, and Oural. This 

 alternating situation of auriferous meridian chains (Vigne has 

 recently visited, on the eastern declivity of Bolos, in the valley 

 of Basha, in Baltistan, the auriferous sands mined, according 

 to the Thibetians, by marmots, and, according to Herodotus, 

 by lai'ge ants) reveals to us this law, that none of the meridian 

 chains just named, between 64° and 75° of longitude, extend 

 themselves upon the adjoining ones, either towards the east 

 or the west, and that each of these longitudinal elevations does 

 not begin to shew its extent, until a point is reached where 

 the preceding has completely disappeared. 2d, Another cha- 

 racteristic trait in the configuration of Asia, and which has 



