At Nimroud discoveries of very considerable importance were made in the high conical mound at the north-west corner. Desirous of fully exploring that remarkable ruin, I had employed nearly all the workmen in opening a tunnel into its western base. After penetrating for no less than eighty-four feet through a compact mass of rubbish, composed of loose gravel, earth, burnt bricks, and fragments of stone, the excavators came to a wall of solid stone masonry. I have already observed that the edifice covered by this high mound was originally built upon the natural rock, a bank of hard conglomerate rising about fifteen feet above the plain, and washed in days of yore by the waters of the Tigris. Our tunnel was carried for thirty-four feet on a level with this rock, which appears to have been covered by a kind of flooring of sun-dried bricks, probably once forming a platform in front of the building. It was buried to the distance of thirty feet from the wall, by baked bricks, broken and entire, and by fragments of stone, remains of the superstructure once resting upon the basement of still existing stone masonry. This mass of rubbish was about thirty feet high, and in it were found bones apparently human, and a yellow earthen jar, rudely colored with simple black designs. The rest of this part of the mound consisted of earth, through which ran two thin lines of extraneous deposit, one _of pebbles_, the other of fragments of brick and pottery. I am totally at a loss to account for their formation. I ordered tunnels to be carried along the basement wall in both directions, hoping to reach some doorway or entrance, but it was found to consist of solid masonry, extending nearly the whole length of the mound. Its height was exactly twenty feet, which, singularly enough, coincides with that assigned by Xenophon to the stone basement of the wall of the city (Larissa).[45] The stones in this structure were carefully fitted together, though not united with mortar, unless the earth which filled the crevices was the remains of mud, used, as it still is in the country, as a cement. They were bevelled with a slanting bevel, and in the face of the wall were eight recesses or false windows, four on each side of a square projecting block between gradines.