Asia is divided laterally along the parallel of 40° north by a depression which, beginning on the east of the desert of Gobi, extends westwards through Mongolia to Chinese Turkestan.
Above sea, and modern researches tend to prove that in the central portions of the Gobi (about Lop Nor) it may be actually below sea-level.
South of the divide the level at once drops to the central depression of Gobi, which forms a vast interior, almost waterless space, where the local drainage is lost in deserts or swamps.
Starting from the Amur river and reaching along the eastern margin of the Gobi desert towards the sources of the Hwangho, it merges into the Altyn-tagh and the Kuen-lun, forming the northern face of the vast Tibetan highlands which are bounded on the south by the Himalaya.
The Pamir highlands between the base of the Tian-shan mountains and the eastern buttresses of the Hindu Kush unite these two great divides, enclosing the Gobi depression on the west; and they would again be united on the east but for the transverse valley of the Amur, which parts the Khingan mountains from the Yablonoi system to the east of Lake Baikal.
6,514,000 The interior or inland basins, including the lacustrine regions south of the Arctic watershed, the Gobi depression, Tibetan plateau, the Iranian (or Perso-Afghan) uplands, the Syro-Arabian inland basin, and that of Asia Minor, amount to 3,141,500 sq.
The broad mountainous slope by which it is connected with the lower levels of Hindostan contains the ranges known as the Himalaya; the name Kuen-lun is generally applied to the northern slope that descends to the central plains of the Gobi, though these mountains are not locally known under those names, Kuen-lun being apparently a Chinese designation.
From it the Oxus, or Amu, flows off to the west, and the Jaxartes, or Syr, to the north, through the Turki state of Khokand, while to the east the waters run down past Kashgar to the central desert of the Gobi, uniting with the streams from the northern slope of the Tibetan plateau that traverse the principalities of Yarkand and Khotan, which are also Turki.
The most important of these ranges is the Tian-shan or Celestial Mountains, which form the northern boundary of the Gobi desert; they lie between 40° and 43° N., and between 75° and 95° E., and some of the summits are said to exceed 20,000 ft.
In 1871-1873 the great Russian explorer, Nicolai Prjevalsky, crossed the Gobi desert from the north to Kansu in western China.
He crossed, and named, the Dzungarian extension of the Gobi desert, and then traversed the Gobi itself from Hami to Sachu, which became a point of junction between his journeys and those of Krishna.
No longer do we regard the Kuen-lun mountains, which extend from the frontiers of Kashmir, north of Leh, almost due east to the Chinese province of Kansu, as the southern limit of the Gobi or Turkestan depression.
Thus between Tibet and the low-lying sands of Gobi we have, thrust in, a system of elevated valleys (Tsaidam), 8000 to 9000 ft.
The great central depression of the continent which reaches from the foot of the Pamir plateau on the west through the Tarim desert to Lop Nor and the Gobi has yielded up many interesting Chinese secrets.
Both rise very gently above it, but have steep slopes towards the lower terrace, which is occupied by the Nerchinsk steppes in Transbaikalia and by the great desert of Gobi in Mongolia (2000 to 2500,ft.
In Transbaikalia and extending farther south-west through the Gobi to East Turkestan.
The eastern Gobi, the occasionally fertile and occasionally sandy plains.
In the hill tracts and the marshy depression of the Ob they are unbroken, except by the bald summits of the loftier mountains (goltsy); they have the aspect of agreeable bosquets in the Baraba steppe, and they are thinly scattered through south-eastern Transbaikalia, where the dryness of the Gobi steppe makes its influence appreciably felt.
As the Gobi desert is approached the forests disappear, the ground becomes covered chiefly with dry Gramineae, and Salsolaceae make their appearance.
In south-east Siberia there are fortythree new species belonging to the north Manchurian or Amur fauna; and in south-east Transbaikalia, on the borders of the Gobi steppe, only 103 species were found by G.
Broadly speaking, Mongolia may be divided naturally into three parts: (1) north-western Mongolia, which occupies the high terrace of the plateau; (2) the Gobi, in its wide sense, covering the lower terrace of the plateau, together with a slightly more elevated and better-watered zone along the western slope of the Great Khingan and its south-western continuation; and (3) southeastern Mongolia, on the eastern slope of the Khingan.
In the same way the Kentei (or Gentei) Mountains, as they are called, to the north of Urga, and the Yablonoi Mountains of Transbaikalia, separate the higher terrace of north-west Mongolia (drained by the tributaries of the Selenga) from the lower terrace of the Gobi, which is drained by the upper tributaries of the Onon and the Kerulen, both belonging to the basin of the Amur.
The rivers which flow down the outer slopes of the border-ridges become lost in the Gobi_ shortly after entering it.
The former, belonging to the Khalkas, occupy the Gobi and the regions of the Kentei Mountains and Khingan Mountains, while the second, divided into numerous minor branches, roam over south-eastern and southern Mongolia.
Inner Mongolia, lying between the desert of Gobi, China proper and Manchuria, is divided into 24 aimaks.
But as each successive range, proceeding south, represents a higher step in the terraced ascent from the desert of Gobi to the plateau of Tibet, the ranges when viewed from the north frequently appear like veritable upstanding mountain ranges, and this appearance is accentuated by the general steepness of the ascent; whereas, when viewed on the other hand from the south, these several ranges, owing to their long and gentle slope in that direction, have the appearance of comparatively gentle swellings of the earth's service rather than of well-defined mountain ranges.
It appears to be a rule that the rivers which eventually terminate in the deserts of Gobi and Takla-makan grow increasingly larger in magnitude from east to west.
The valley, known by the general name of Kakir, meaning a " hard, dry, sterile expanse of clay," is chequered with shallow selfcontained basins of the usual type and has remarkably gentle slopes ' The Northern Mountains are the Pe-shan in the desert of Gobi (see Gobi).
The succession of ranges which follow one another from the deserts of Takla-makan and Gobi up to the plateau proper of Tibet rise in steps or terraces, each range being higher than the range to the north of it and lower than the range to the south of it.
Thus we have in the northern hemisphere the Sahara desert, the deserts of Arabia, Iran, Turan, Takla Makan and Gobi, and the desert regions of the Great Basin in North America; and in the southern hemisphere the Kalahari desert in Africa, the desert of Australia, and the desert of Atacama in South America.
The "master of the law," as his biographers call him, plunged alone into the terrible desert of the Gobi, then known as the Sha-mo or "Sand River," between Kwa-chow and Igu (now Hami or Kamil).
The name is derived from that of the Ta-ta Mongols, who in the 5th century inhabited the north-eastern Gobi, and, after subjugation in the 9th century by the Khitans, migrated southward, there founding the Mongol empire under Jenghiz Khan.
Between November 1870 and September 1873, accompanied by only three men and with ridiculously small pecuniary resources, he crossed the Gobi desert, reached Peking, and, pushing westwards and south-westwards, explored the Ordos and the Ala-shan, as well as the upper part of the Yangtsze-kiang.