TIGRIS, next to the Euphrates, the greatest river of former Asiatic Turkey; rises on the S. slope of the Armenian Taurus range in Kurdistan to the S. of Lake Goljik. It has a sinuous course in a S. E. direction, almost parallel to that of the Euphrates, which river it joins at Kurna, after a course of 1,060 miles. The joint stream, called the Shat-el-Arab, after a further course of 90 miles, enters the head of the Persian Gulf. In its upper course the Tigris flows through fine pasture land, frequented by nomad Kurds and Arabs, and from Diarbekir, where it becomes navigable for small craft, to Mosul, a distance of 200 miles, its banks are high ly cultivated in some places. Below this point, again, as far as Bagdad (250 miles), it traverses unpeopled wastes, while from Bagdad to its mouth the steep banks are overgrown with high reeds and brushwood, and are haunted by lions and other beast of prey. Its afflueras, the Bitlis, Great and Little Zab, the Dyala, all flow from the highlands to the N.,
the country separating it from the Euphrates being a streamless waste. The chief places on the Tigris are Diarbekir, Mosul, and Bagdad, and the ruins of Nineveh, Selucia, Ctesiphon, and Opis. Like the Euphrates, the Tigris rises in spring with the melting of the snow on the Armenian Mountains; and during the latter half of May, when the flood is at its height, the whole country between and beyond these rivers, for over 100 miles between Bagdad and Bussorah, is converted into a lake. The arrowy stream either loses less water by irriga tion or receives more from its affluents than the Euphrates, for it is the larger of the two at the point of confluence. In the World War the Tigris was the scene of heavy fighting between the Turkish and Anglo-Indian armies in 1915, 1916 and 1917.