The chapel which has been found on the north side of the Pool of Siloam appears to be somewhat later than this wall. It is not mentioned by any writer before 570 A. D., and it may have been built under Justinian. The pool--as described by Antoninus Martyr--was then converted into a baptistery, and the chapel was no doubt used in connection with the rites. The reservoir was divided into two parts by rails. In one part men were washed, in the other women, “for a blessing,” and the intermittent flow from the tunnel was awaited. The waters were said to cure leprosy--no doubt with reference to the Gospel story.[427] As late as the eleventh century[428] a Moslem writer informs us, in speaking of Siloam, “there are at this spring many buildings for charitable purposes, richly endowed”; but these were apparently not kept up, and the chapel is not noticed in the accounts of the Middle Ages. The institution is mentioned by Nâṣr-i-Khosrau in connection with the hospice in the city itself (afterwards that of St. John), which dated from about 800 A. D. It is, however, possible that both these charitable institutions originated with Justinian, who certainly erected others on the Temple hill. [Sidenote: THE MOSAIC MAP] The mosaic map of Jerusalem, perhaps about 450 A. D., has already been noticed.[429] It shows very clearly Constantine’s Church of the Anastasis, with the great roofless apse on the west, the basilica to its east having a pitched roof, while the atrium seems also to be roofless, and the porch gates stand above steps leading down to the pillared street close by to the east. The representation of the city is a rude perspective, and the main buildings are quite out of scale. The pillared street ascends to Zion by steps at right angles to its course, which is north and south through the middle of the city. The walls are strengthened by towers such as have been actually unearthed on the south. Three city gates are shown on west, north, and east. The only building on the Temple site is at the south-east corner--apparently the “Chapel of St. Simeon” in the old Herodian vault, where the “Cradle of Christ” was early shown. The second pillared street, west of the Temple, descends towards Siloam by steps, and Antoninus Martyr,[430] in the sixth century, speaks of descending this street under the “arch” of the causeway, which then led to the central gate of the west Temple wall, and “by many steps” down to Siloam. The Church of St. Anne is shown in the north-east part of the city, and a large church inside the wall on the south-west is probably St. Sion.[431] The House of Annas appears to its north, with three other buildings--two east of the central street.