The great palace was a building of still larger dimensions than the great temple. According to Diodorus, it was situated within a triple enclosure, the innermost wall being twenty stades, the second forty stades, and the outermost sixty stades (nearly seven miles), in circumference. The outer wall was built entirely of plain baked brick. The middle and inner walls were of the same material, fronted with enamelled bricks representing hunting scenes. The figures, according to this author, were larger than the life, and consisted chiefly of a great variety of animal forms. There were not wanting, however, a certain number of human forms to enliven the scene; and among these were two--a man thrusting his spear through a lion, and a woman on horseback aiming at a leopard with her javelin--which the later Greeks believed to represent the mythic Ninus and Semiramis. Of the character of the apartments we hear nothing; but we are told that the palace had three gates, two of which were of bronze, and that these had to be opened and shut by a machine. But the main glory of the palace was its pleasure-ground--the “Hanging Gardens,” which the Greeks regarded as one of the seven wonders of the world. This extraordinary construction, which owed its erection to the whim of a woman, was a square, each side of which measured 400 Greek feet. It was supported upon several tiers of open arches, built one over the other, like the walls of a classic theatre, and sustaining at each stage, or story, a solid platform, from which the piers of the next tier of arches rose. The building towered into the air to the height of at least seventy-five feet, and was covered at the top with a great mass of earth, in which there grew not merely flowers and shrubs, but tress also of the largest size. Water was supplied from the Euphrates through pipes, and was raised (it is said) by a screw, working on the principal of Archimedes. To prevent the moisture from penetrating into the brick-work and gradually destroying the building, there were interposed between the bricks and the mass of soil, first a layer of reeds mixed with bitumen, then a double layer of burnt brick cemented with gypsum, and thirdly a coating of sheet lead. The ascent to the garden was by steps. On the way up, among the arches which sustained the building, were stately apartments, which, must have been pleasant from their coolness. There was also a chamber within the structure containing the machinery by which the water was raised.