progress, was evidently well understood, and in spite of the amount of force applied in front, it would have been difficult to give the first impetus to so great a mass, a lever was skilfully applied behind to raise the hind part of the sledge slightly, and so propel it forward, while to secure a sound and firm fulcrum, wedges of wood were inserted between the lever and the ground. The greater power of a lever at a distance from the fulcrum being known, ropes were attached to its upper end, which could not otherwise have been reached, and the lever was worked by means of them. We have thus unimpeachable evidence as to the mode whereby the conveyance of huge blocks of stone along level ground was effected. But it may be further asked, how were the blocks raised up to the elevation at which we find them placed? Upon this point there is no direct evidence; but the probability is that they were drawn up inclined ways, sloping gently from the natural ground to the top of the platforms. The Assyrians were familiar with inclined ways, which they used almost always in their attacks on walled places, and which in many cases they constructed either of brick or stone. The Egyptians certainly employed them for the elevation of large blocks; and probably in the earlier times most nations who affected massive architecture had recourse to the same simple but uneconomical plan. The crane and pulley were applied to this purpose later. In the Assyrian sculptures we find no application of either to building, and no instance at all of the two in combination. Still each appears on the bas-reliefs separately--the crane employed for drawing water from the rivers, and spreading it over the lands, the pulley for lowering and raising the bucket in wells. [PLATE LXXXIX., Fig. 3.] [Illustration: PLATE 89]