Strong tides ascend these rivers to the distance of 400 miles, and for the time prevent the descent of the fresh water, which forms large interior seas frequented by thousands of trading-vessels, and they irrigate the productive lands of central China, from time immemorial the most highly cultivated and the most densely-peopled region of the globe. Almost all the Chinese rivers of less note—and they are numerous—feed these giant streams, with the exception of the Ta-si or Hong-Kiang and the Pee-ho or White River, which have their own basins. The former, rising to the east of the town of Yun-nan, flows through the plains of Canton eastward to the Gulf of Canton, into which it discharges itself, increased in its course by the Sekiang. The White River, rising in the mountains near the Great Wall, becomes navigable a few miles east of Pekin, unites with the Eu-ho, joins the Great Canal, and, as the tide ascends it for 80 miles, it is crowded with shipping. The Amur, the sources of which are partly in the Russian dominions, though its course is chiefly in the Mantchoo territory of China, is 2000 miles long, including its windings, and has a basin of 853,000 square miles. Almost all its tributaries come from that part of the Baikalian group called the Yablonnoi Khrebit by the Russians, and Khing-Khan-Oola by the Chinese. The river Onon, which is the parent stream, has its origin in the Khentai Khan, a branch of the latter; and though its course is through an uninhabited country, it is celebrated as being the birthplace and the scene of the exploits of Tshingis Khan. After passing through the lake of Dalai-nor, which is 210 miles in circumference, it takes the name of Argun, and forms the boundary between the Chinese and Russians for 400 miles; it is then joined by the Shilka, where it assumes the Tunguse name of the Amur or Great River: the Mandchoos call it the Sagalin or Black Water. It receives most of the unknown rivers which come from the mountain-slopes of the Great Gobi, and falls into the Pacific opposite to the island of Sagalin, after having traversed three degrees of latitude and thirty-three of longitude.