Easton's Bible Dictionary (1897)
Fountain of the sun a spring which formed one of the landmarks on the boundary between Judah and Benjamin (Josh. 15:7; 18:17). It was between the “ascent of Adummim” and the spring of En-rogel, and hence was on the east of Jerusalem and of the Mount of Olives. , the “well of the apostles” about a mile east of Bethany, the only spring on the road to Jericho. The sun shines on it the whole day long.
Hastings' Dictionary of the Bible (1898) & Schaff's Bible Dictionary
EN-SHE'MESH (*fountain of the Sun), a spring between Judah and Benjamin, Josh 15:7; Josh 18:17; probably the same as that now called the "Apostle's Spring," about 1 1/2 miles east of Bethany, and the first halting-place for travellers from Jerusalem to Jericho.
Hitchcock's Bible Names (1869)
fountain, or eye, of the sun