1866.] Tableau of High Asia. 53 



In the Andes are to be found, if not the highest, at least the most 

 extensive plateaux of our globe, which generally lie along the very 

 ridge of the mountains, and on which large towns are situated, as 

 Cerro de Pasco (14,098 ft.), Potosi (13,665 ft.), and Cuzco (11,380 

 ft.). There is also a large plateau surrounding the elevated lake 

 Titicaca (12,843 ft.). 



In the Alps, plateaux occur only at their base; the Swiss plateau 

 having a mean height of 1,460 ft., the Suevo- Bavarian plateau of 

 1,420 ft. 



2. Passes. 



The mean of a sufficient number of such passes, which lead over the 

 principal crests, is particularly to be taken into consideration, it being 

 approximative^ proportional, or, to express it more clearly, equal to 

 the general mean height of these crests. The passes situate in the 

 lateral ramifications of the principal crests — though they are numerous 

 — cannot be included in these general means, being geographically 

 of subordinate importance. 



The mean height of passes in the three principal mountain-chains 

 of High Asia is as follows : 



A. For the Himalaya (mean of 19 passes,) 17,800 ft. 



From Sikkim to Kishtvar : Bhutan and Kashmir being excluded : 



the former for want of materials, and Kashmir on account of the 

 Himalaya there losing the character of one well-defined and predomi- 

 nant chain. 



B. For the Kardkorum (mean of 3 passes,) ...18,700 ft. 



From long. E. Gr. 76° to 79J°, the heights in the eastern continu- 

 ation being quite unknown. 



C. For the Kiinliin (mean of 2 passes,) 17,000 ft. 



As the two passes are situated in parts not differing in any particu- 

 lar from the general mean of this chain, they may be looked upon as 

 representatives of the other. 



From these numbers it appears, that the Karakorum has by far the 

 greatest mean height of passes ; but the one pass which we must still 

 consider the highest, is situated in the Himalaya. This is the Ibi 

 Gamin pass (20,459 ft.) leading from Garhval to Grnari Khorsum, 

 which my brother Aclolphe and I myself crossed as the first, and as 

 yet as the only Europeans, Aug. 22, 1855. The pass next in height 



