The total population of the islands is estimated at nearly 60,000, all of them Moslems with the exception of about 100 Banian traders from Sindh, India. Menamah, the large town on the northeast point of the island, with perhaps 10,000 inhabitants, is built along the shore for about a mile; the houses are mostly poor, many being mere mat-huts. This town is the market-place and commercial centre for the whole group. Here is the post office and custom-house and here the bulk of the trade is carried on for the whole island. A short distance from Menamah is the old town of Belad le Kadim, with ruins of better buildings and a fine mosque with two minarets. The mosque is of very early date, for the older Cufic character is on all its inscriptions, covered over in some places by more recent carving and inscriptions in later Arabic. The largest spring on the islands is called El Adhari, “the virgins.” It issues from a reservoir thirty yards across, and at least thirty feet deep, flowing in a stream six or eight feet wide and two feet deep. This is remarkable for Arabia, and gives some idea of the abundant supply of water. Under the sea, near the island of Moharrek, are fresh-water springs always covered with a fathom of salt water. The natives lower a hollow, weighted bamboo through which the fresh water gushes out a few inches above sea-level. The source of these fresh-water springs of Bahrein must be on the mainland of Arabia, as all the opposite coast shows a similar phenomena. Apparently the _River Aftan_ marked on old maps of the peninsula as emptying into the Persian Gulf near Bahrein was an _underground river_, known to the older geographers.