Tigris
(ὁ Τίγρις). A great river of western Asia, rises from several sources on the south side of that part of the Tauris chain called Niphates, in Armenia, and flows southeast, first through the narrow valley between Mount Masius and the prolongation of Mount Niphates, and then through the great plain which is bounded on the east by the lastnamed chain, till it falls into the head of the Persian Gulf, after receiving the Euphrates from the west.