But besides these covered cisterns in the houses and courts, there are many large open reservoirs in and around the city. In the upper part of the Valley of Hinnom, west of the city, is the _Birket el Mamilla_, often called the Upper Pool of Gihon. Lower down in the same valley, and not far from the south-western angle of the city wall, is the _Birket es Sultan_, frequently called the Lower Pool. Because these pools are clearly related to one another as upper and lower, it has been usual to assume that they are upper and lower pools of Gihon, which seem to be referred to in 2 Chron. xxxii. 30, and elsewhere. But although the Sultan’s Pool has been called Gihon from the fourteenth century downwards, it is known to have been constructed by the Germans only two centuries before, and the word Gihon means a spring-head. From the Sultan’s Pool we may ride down the deep valley, on the south bank of which are the traditional Aceldama and the tombs of many Christian pilgrims, till we come to _Bir Eyub_ (Joab’s Well), where the Valley of Hinnom unites with the Valley of Kedron. The Crusaders, who were never too well informed, identified Joab’s Well with the Biblical En Rogel. From this place we ride northward to the junction of the Kedron with the Tyropœon, and there, in a verdant spot, we find the Pool of Siloam, with dry stone walls and a little muddy water. With the village of Siloam on our right, we ride up the Kedron Valley some 300 yards, and arrive at the Fountain of the Mother of Stairs, also called the Virgin’s Fountain. Descending by a flight of sixteen steps we reach a chamber, its sides built of old stones and its roof formed of a pointed arch. Then going down fourteen steps more into a roughly hewn grotto, we reach the water. _Mejr ed Deir_ states that the water of this fountain was a great test for women accused of adultery; the innocent drank harmlessly, but the guilty no sooner tasted than they died! When the Virgin Mary was accused, she submitted to the ordeal, and thus established her innocence. Hence the spring was long known as the Fountain of Accused Women. Dr Robinson imagined that this was the true Bethesda, because the water is considered to possess healing virtue, and every day crowds of men and women, afflicted with rheumatism and other maladies, descend the steps and wait for the moving of the waters. The flow is intermittent--due, it is supposed, to a natural syphon--and the waters rise suddenly, immersing the folks, fully clothed, nearly up to the neck. The water wells up in the cave, and when it has attained a height of 4 feet 7 inches runs away through a passage near the back, into a small tunnel, and goes to supply the Pool of Siloam. About 100 yards north-east of St Stephen’s Gate is the Pool of My Lady Mary, outside the walls.