ANNOTATIONS AND ADDITIONS. 75 



is, in the south between Ladak, Gertop, and H'lassa, (the 

 seat of the great Lama,) 720 geographical miles ; between 

 Kami in the Celestial Mountains, and the great bend of the 

 Hoang-ho near the In-schan chain, hardly 480 ; and in 

 the north, between the Khanggai, where the great city of 

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

 which runs north and south (in the part of the Gobi tra- 

 versed in travelling from Kiachta by Urga to Pekin) 760 

 geographical miles. The whole extent of this swelling 

 ground, which must be carefully distinguished from the far 

 more elevated mountain range to the east, may be approxi- 

 mately estimated, taking its inflections into account, at 

 about three times the area of Trance. The map of the 

 mountain ranges and volcanoes of Central Asia (Carte der 

 Bergketten und Yulkane von Central- Asien), constructed 

 by me in 1839, but not published 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 determina- 

 tions accessible to me, and on a vast amount of orographic 

 description, in which Chinese literature is beyond measure 

 rich, examined at my request by Klaproth and Stanislas 

 Julien. My map marks the mean direction and the height 

 of the mountain chains, and represents the leading features 

 of the interior of the continent of Asia, from 30 to 60 

 degrees of north latitude, and between the meridians of 

 Kherson and Pekin. It differs materially from any pre- 

 viously published map. 



The Chinese have enjoyed a threefold advantage towards 



