the whole mass of the mountains and plateaus of Asia were uniformly spread over its surface, the continent would rise no less than 2,885 feet above the sea, while Africa and North America would respectively reach only 2,165 and 1,950 feet. High plateaus occupy nearly two-fifths of its area. One of them, that of western Asia, including Anatolia, Armenia, and Iran, extends in a southeasterly direction from the Black Sea to the valley of the Indus; while the other, the high plateaus of eastern Asia, still loftier and much more extensive, stretches N. E. from the Himalayas to the northeastern extremity of Asia, re sembling in shape a South America point ing N. E., and meeting Bering Strait, the northwestern extremity of the high plateau of North America.
four rivers, the Mis sissippi, Amazon, Kongo, and Nile, sur pass the largest rivers of Asia, the Yenisei and the Yangtse-kiang, both as to length and drainage areas; but owing to the scarcity of rain over large parts of Asia, the amount of water carried down by the largest rivers is, as a rule, disproportionately small as compared with American or European rivers. The predominant feature of Asia's hydrography is the existence of very wide areas having no outlet to the sea. On the great plateau of eastern Asia, the region which has no outlet from the plateau, and whose water does not reach even Lake Aral or the Caspian, covers a surface larger than that of Spain, France„ and Germany together. It is watered only by the Tarim, which supplies some irrigation works in its upper parts, and enters the rapidly dry ing marshes of Lob-nor. This area is steadily increasing, and since 1862 we have had to add to it the drainage area (as large as England and Wales) of the Keruleii, which empties into Dalai-nor, but no longer reaches the Arguti, a tributary of the Amur. The Ulyasutai River and the Tchagantogoi now no longer reach Lake Balkash; and the Ur ungu, which obviously joined the Upper Irtysh at no very remote date, empties into a lake separated from the Black Irtysh by a low isthmus not 5 miles wide. If we add to this the drainage basins of Lake Balkash with its tributaries, the Ili and other smaller rivers; the great Lake Aral, with the Syr-daria (Jaxartes) and Amudaria (Oxus), as also the nu mero is rivers which flow toward it or its tributaries, but are desiccated by evaporation before reaching them, and finally the Caspian with its tributaries, the Volga, Ural, Kura, and Terek, we find an immense surface of more than 4,000,000 square miles; that is much larger than Europe, which has no outlet to the ocean. The plateaus of Iran and
Armenia, two separate areas in Arabia, and one in Asia Minor, represent a sur face of 5,567,000 square miles.
The drainage area of the Arctic Ocean includes all the lowlands of Siberia, its plains and large portions of the great plateau. The chief rivers flowing N. to the Arctic Ocean are the Obi, with the Irtysh; the Yenisei, with its great tribu tary, the Angara, which brings to it the waters of Lake Baikal, itself fed by the Selenga, the Upper Angara, and hun dreds of small streams; and finally the Lena, with its great tributaries, the Vitim, Olekma, Vilui, and Aldan. Three great navigable rivers enter the Pacific: the Amur, composed of the Arguri and Shilka, and receiving the Sungari, a great artery of navigation in Manchuria, the Usuri and the Zeya; the Hoang-ho; and the Yangtse-kiang, the last two ris ing on the plateau of Tibet. Freighted boats penetrate from the seacoast to the very heart of China. The Cambodia, or Mekong, the Salwen, and the Irawadi, rising in the eastern parts of the high plateau, water the Indo-Chinese peninsula. Rising on the same height, the Indus and the Brahmaputra flow through a high valley in opposite di rections along the northern base of the Himalayas, until both pierce the gigantic ridge at its opposite ends, and find their way, the former to the lowlands of the Punjab, where it is joined by the Sutlej, and the latter to Assam and Bengal, where it joins the great river of India, the Ganges, before entering the Gulf of Bengal by a great number of branches forming an immense delta. The plateau of the Deccan is watered by the Goda vari and Krishna, flowing E., the Nar bada, flowing W., and a great number of smaller streams. The Tigris and Euphrates, both rising in the high pla teau of Armenia, flow parallel to each other, bringing life to the valley of Mesopotamia, and join before entering the Persian Gulf. Arabia proper has no rivers worthy of notice. The Irmah, which enters the Black Sea, is the only river worthy of notice in Asia Minor. In Caucasus, the Rion and Kuban enter the Black Sea, and the Kura and Terek, the Caspian.