ILLTJSTKATIONS (10). THE PLATEAUX OF ASIA. 57 



mils, 011 account of the periodical performance of sacrifices, in 

 accordance with pre-existing enactments; and lastly, the early 

 and generally known use of the compass for determining the 

 direction of mountains and rivers. This use, and the know- 

 ledge of the south-pointing of the magnetic needle, twelve 

 centuries before the Christian era, gave a great superiority 

 to the orographic and hydrographic descriptions of the Chinese 

 over those of Greek and Roman authors, who treated less fre- 

 quently of subjects of this nature. The acute observer Strabo 

 was alike ignorant of the direction of the Pyrenees and of 

 that of the Alps and Apennines.* 



To the lowlands belong almost the whole of Northern 

 Asia to the north-west of the volcanic Celestial Mountains 

 (Thian-schan) ; the steppes to the north of the Altai and 

 the Sayanic chain; and the countries which extend from 

 the mountains of Bolor, or Bulyt-tagh (Cloud Mountains in 

 the Uigurian dialect), which run in a north and south 

 direction, and from the upper Oxus, whose sources were dis- 

 covered in the Pamershian Lake, Sir-i-kol (Lake Victoria), 

 by the Buddhist pilgrims Hiuen-thsang and Song-yun in 518 

 and 629, by Marco Polo in 1277, and by Lieutenant Wood in 

 1838, towards the Caspian Sea; and from Lake Tenghiz or 

 Balkasch, through the Kirghis Steppe, towards the Aral and 

 the southern extremity of the Ural Mountains. In the vicinity 

 of mountainous plains, w r hose elevation varies from 6000 to 

 more than 10,000 feet above the sea's level, we may assuredly 

 be allowed to apply the term lowlands to districts which arc 

 only elevated from 200 to 1200 feet. The first of these 

 heights correspond with that of the city of Mannheim, and 

 the second with that of Geneva and Tubingen. If we extend 

 the application of the word plateau, which has so frequently 

 been misused by modern geographers, to elevations of the 

 soil which scarcely present any sensible difference in the cha- 

 racter of the vegetation and climate, physical geography, 

 owing to the indefiniteness of the merely relatively important 

 terms of high and low land, will be unable to distinguish 

 the connexion between elevation above the sea's level and 

 climate, between the decrease of the temperature and the 

 increase in elevation. When I was in. Chinese Dzungarei, 



* Compare Strabo, lib. ii. pp. 71, 128; lib. iii. p. 137; lib. iv. pp. 

 199, 202; lib. v. p. 211, Casaub. 



