Unless Solomon built the wall which ran from Maudsley’s scarp at the northwest corner of the western hill eastward down the slope of that hill to the southern point of the eastern hill, it must have been built by some king of this period. No hint is given us as to who built this wall. It may have been done in the reign of Jehoshaphat, which was a period of prosperity and expansion (2 Kings 3:4-12), or in the reign of Uzziah, which was also a very prosperous time. The need of stronger defenses created by the advance of the Assyrians into western Asia in the ninth and eighth centuries B. C. makes it probable that Uzziah was the builder. At all events it was accomplished by the time of Hezekiah. In the reign of Ahaz there was a conduit (Isa. 7:3) leading from the “upper pool,” or Gihon, to a lower pool, which probably lay somewhere near the mouth of the Tyropœon valley. This conduit has been discovered. It was designed partly to conduct water from Gihon out into the valley of the Kidron for the irrigation of the king’s gardens, and partly to fill the lower pool so that cattle could come and drink. Isaiah refers to the waters of this conduit as “the waters of Shiloah that go softly” (Isa. 8:6). Of course, this conduit was in Isaiah’s time an old one. It is impossible to tell when it was first constructed. It may have been made as early as the time of Solomon or David, or even in Jebusite times. In the reign of Ahaz a change was made in the nature of the altar of burnt-offerings in the temple. When Ahaz went to Damascus to do homage to Tiglath-pileser IV of Assyria, he saw an altar that pleased him, and sent a pattern of it home to the high priest, Urijah, with directions to have one made like it for the temple. This Urijah did. This altar was apparently constructed of stone. It displaced the brazen altar of Solomon, which was henceforth kept for the king’s private use (2 Kings 16:10-16). It is thought by some that the measurements of this stone altar are reproduced in Ezekiel 43:13-17. The brazen altar had always been out of accord with the Hebrew law. (See Exod. 20:24-26.)