88 STEPPES AND DESERTS. 



great snow-covered massive elevation Bogdo-Oola ; the Sol- 

 fatara of (Jrumsti, which furnishes sulphur and sal-ammoniac 

 (nao-scha), and is situated in a coal district ; the still active 

 volcano of Turfan (or volcano of Ho-tscheu or Bischbalik), 

 almost midway between the meridians of Turfan (Kune- 

 Turpan), and of Pidjan. The volcanic eruptions of the 

 Thian-schan chain, recorded by Chinese historians, reach 

 as far back as the year 89, A.D., when the Hiongnu 

 of the sources of the Irtysh were pursued by the Chinese 

 army as far as TCutch and Kharaschar (Klaproth, Tableau 

 hist, de TAsie, p. 108). The Chinese General, Teu-hian, 

 surmounted the Thian-schan, and saw "the Fire Moun- 

 tains which send out masses of molten rock that flow for 

 many Li." 



The great distance from the sea of the volcanoes of the 

 interior of Asia is a remarkable and solitary phenomenon. 

 Abel Eemusat, in a letter to Cordier (Annales des Mines, T. 

 v. 1820, p. 137), first directed the attention of geologists to 

 this fact. The distance, for example, in the case of the volcano 

 of Pe-schan, to the north, or to the Icy Sea at the mouth of the 

 Obi, is 1528 geographical miles ; to the south, or to the 

 mouths of the Indus and the Ganges, 1512 geographical 

 miles ; to the west, 1360 geographical miles to the Caspian 

 in the Gulf of Karaboghaz ; and to the east, 1020 geogra- 

 phical miles to the shores of the sea of Aral. The active 

 volcanoes of the New World were previously supposed to 

 offer the most remarkable instances of such phenomena at a 

 great distance from the sea ; their distance, however, is only 

 132 geographical miles in the case of the volcano of Popo- 



