TIAN-SHAN, shiin', or CELESTIAL MouNTAIN8. A great mountain system of Cen tral Asia. It begins in the southeastern part of Russian Turkestan, and extends in an eastward direction for nearly 1500 miles across East Turk estan toward the Desert of Gobi, in which it is gradually lost (Map: Persia, N 2). It forms the northern boundary of the great Tarim Basin, which it separates from the watersheds of Lake Balkash and the Syr-Darya. It is connected by broken ranges with the Altai Mountains to the north. The system consists almost through out its length of a number of parallel ranges with a total width of about 200 miles. In the central portion there is a main ridge forming an unbroken wall covered with per petual tillOW throughout its length, and culminat ing in the west in the Khan-Tengri, a peak bear ing enormous glaciers and reaching an altitude of 24,000 feet. East of this ridge the mountains descend in a broad plateau with scattered peaks and ridges from 6000 to 10,000 feet high. West
of the Khan-Tengri the system spreads out like a fan with numerous branches which finally lose themselves in the plains of Russian Turkestan. One of these ranges runs into the Pamir (q.v.), where, through the Sarikol, it connects with the Kuen-lun, Hindu-Kush, and Himalaya systems. In this western portion there are several impor tant passes affording routes between Russian and East Turkestan. The system Meioses numerous large longitudinal valleys whose bottoms form wide steppe regions. Above these the slopes are covered with immense spruce forests succeeded by an alpine flora to the snow-line. The loftiest group in the eastern portion, the Bogdo-ola, is held sacred by the Mongolians, and figures promi nently in their religious mythology.