Persian Gulf
an arm of the Indian Ocean which penetrates between Arabia and Persia to the extent of 650 miles in a general N. W. direction. Its breadth varies from 55 miles at the mouth to 250 miles, and the area is estimated at 77,450 square miles, not including the islands, which are scattered over the W. half, or lie close inshore along the E. side. The chief of these islands are Ormuz, at the mouth; Kishm, 810 square miles in extent; and the Bahrein Islands.
The Great Pearl Bank stretches along the W. side from Ras Hassan to nearly half way up the gulf. The coast is mostly formed of calcareous rocks.
With the exception of the Shat-el-Arab, the Persian Gulf receives only insignificant streams. Its E. side presents abundance of good anchorage, either in the numerous bays or in the lee of is lands. The greater portion of its S. shores now belongs to the Imam of Muscat, while the whole of the N. shore belongs to Persia. The order of the periodic currents in this gulf is precisely the reverse of that of the Red Sea currents, as they ascend, from May to October, and descend from October to May. The greatest depth does not exceed 50 fathoms.
The submarine telegraph cables belonging to the government of India, and forming part of the system of the Indo- European Telegraph, pass through the whole length of the Persian Gulf. The pearl fisheries employed before the World War 70,000 men and 6,000 barks.