Of the remaining buildings on this side, we have nothing of importance to communicate owing to the unfinished state of the excavations, nor is there much to report with regard to the buildings to the south of the Western Court: only a part of the Great Hall is excavated. We recognise the additional building, with its wall pushed towards the north. It is built with the two-ridged bricks of Nebuchadnezzar, and the peculiar effect of this method of building can here be seen clearly (Fig. 71). Behind the hall we again find a series of three chambers, all apparently similar to each other, such as we find behind the great halls of the Principal and Central Courts. In the chambers next to court 40 are two circular walled-in wells, and in each case the foundation of the chamber that contains them is also filled in with rubble brickwork. XVII THE FORTIFICATION WALLS TO THE NORTH AND SOUTH OF THE PALACE OF NABOPOLASSAR. [Illustration: FIG. 72.—Door in south wall of Southern Citadel. ] In the fortification wall south of Nabopolassar’s palace, which has been excavated to a considerable depth, Nebuchadnezzar’s bricks occur even in the lower courses, while close by on the east the bricks are unstamped. There is an opening here in the wall to form an exit for the drain which runs from the Principal Citadel through the long passage. The three arched openings (Fig. 72) are very remarkable. They resemble doorways, but they have no rabbets, such as are usually found in this kind of archway. The bricks are laid in asphalt and reeds. [Illustration: FIG. 73.—South wall of the Nabopolassar Palace, from the west. ] At about 7 metres above zero, near this old wall another wall begins, which is also constructed with Nebuchadnezzar’s bricks. It rests on a projecting smooth foundation, and its towers do not correspond with those of the lower wall. In order to form a base for this projecting foundation the space between the palace and the old wall was filled up with brickwork (Fig. 68), divided into separate blocks, each of which overlaps its neighbour in stepped fashion. This in a sense forms the exact contrary of the expansion joint, and the builders must have calculated that in this case the unequal sinking occurred so completely and satisfactorily during the course of the building that the whole of the upper portions might safely be bonded together in one solid mass. Outside a strengthening kisu is added, which permits of the opening of the doors, but which cuts off the outlet for the drain (Fig. 73). Where the later building is joined on, a grid of wooden beams laid at right angles to each other is inserted. The later building can be easily recognised on the whole of the southern side, but here it is especially clear. [Illustration: FIG. 74.—Foundation of the fortification wall north of the Southern Citadel. ]