At the bottom of the shaft, which is 67 feet due west, Warren found the rock scooped out into a basin 3 feet deep, for the water to lie in, and at the top of the shaft an iron ring to which the rope of the bucket could be tied. The shaft was 40 feet in height, and then the space began to open out westward into a great cavern, there being a sloping ascent at an angle of 45°, covered with loose stones of about a foot cube. Warren says it was ticklish work ascending, for the stones all seemed longing to be off, and one starting would have sent the mass rolling, himself with it, on top of the serjeant, all to form a mash at the bottom of the shaft. After ascending about 30 feet they got on to a landing. The cave now opened out to south-west and north-west. Following it in the latter direction they arrived at a passage 40 feet long, at the far end of which was a rough wall. Creeping through a hole in this they ascended a steep staircase for 50 feet, passed another wall, and found themselves in a vaulted chamber. The exit at last was on the Hill of Ophel, a few feet from the ridge, and almost certainly, some writers maintain, within the ancient walls. The object of the cuttings was to get a supply of water from within; and perhaps the piles of loose stones which were found in the long passage were intended to be thrown down the shaft if an enemy should attempt to ascend it. In the passage were found three glass lamps of curious construction, placed at intervals as if to light the way; and in the vaulted chamber a little pile of charcoal as if for cooking, one of these lamps, a cooking dish glazed inside, for heating food, and a jar for water. Evidently the place had been used as a refuge. A similar arrangement for closing the entrance to a spring, and using a secret passage from the hill above, has lately been discovered at _El Jib_ (ancient Gibeon),[24] and only a few years ago at ’_Amman_ (Rabbath Ammon). In connection with the latter, Conder quotes Polybius to the effect that when Antiochus the Great besieged the forces of Ptolemy Philopater, at _Amman_, in 218 B.C., the garrison held out until a prisoner revealed a secret communication with a water supply outside the walls.