66 VIEWS OF NATURE. 



cast longitude from Greenwich. Measured at right angles t4 

 its longitudinal axis, its breadth in the south, between Ladak, 

 Gertop, and H'lassa (the seat of the great Lama), is 720 miles; 

 between Hami in the Celestial Mountains, and the great curve 

 of the Hoang-ho, near the In-schan chain, it is scarcely 480; 

 but in the north, between the Khanggai, where the great city 

 of Karakhorum once stood, and the chain of Khin-gan-Petscha, 

 which runs in a meridian line (in the part of Gobi traversed in 

 going from Kiachta to Pekin by way of Urga), it is 760 miles. 

 The whole extent of this elevated ground, which must be care- 

 fully distinguished from the more eastern and higher mountain- 

 range, may be approximately estimated, including its deflec- 

 tions, at about three times the area of France. The map of 

 the mountain-ranges and volcanoes of Central Asia, which I 

 constructed in 1839, but did not publish until 1843, shows in 

 the clearest manner the hypsometric relations between the 

 mountain-ranges and the Gobi plateau. It was founded on 

 the critical employment of all the astronomical determinations 

 accessible to me, and on many of the very rich and copious 

 orographic descriptions in which Chinese literature abounds, 

 and which were examined at my request by Klaproth and Sta- 

 nislaus Julien. My map marks in prominent characters the 

 mean direction and the height of the mountain-chains, toge- 

 ther with the chief features of the interior of the continent of 

 Asia from 30 to 60 degrees of latitude, between the meridians 

 of Pekin and Cherson. It differs essentially from any map 

 hitherto published. 



The Chinese enjoyed a triple advantage, by means of 

 which they were enabled to enrich their earliest literature 

 with so considerable an amount of orographic knowledge re- 

 garding Upper Asia, and more especially those regions situated 

 between the In-schan, the alpine lake of Khuku-noor, and 

 the shores of the Hi and Tarim, lying north and south of the 

 Celestial Mountains, and which were so little known to 

 Western Europe. These three advantages were, besides the 

 peaceful conquests of the Buddhist pilgrims, the warlike 

 expeditions towards the west (as early as the dynasties of 

 Han and Thang, one hundred and twenty-two years before our 

 era, and again in the ninth century, when conquerors ad- 

 vanced as far as Ferghana and the shores of the Caspian Sea), 

 the religious interest attached to certain high mountain sum- 



