We cannot at present decide the question, but we shall not be far wrong if we assume that the ordinary house was on one floor. Certain dwellings, on the contrary, may have had upper storeys, in which case wooden steps may have formed the means of communication. The Principal Court occupies an imposing site 55 metres broad by 60 metres long. Like the others, it was paved with tiles, and towards the close of the Sassanide period it was used for burials. Endless shallow coffins either of trough or slipper shape, made of terra-cotta, and frequently in blue glaze, were deposited in the soil as low as the earliest floor-level, and frequently one above another. The brick robbers have left them displaced and smashed to pieces. Exactly in the centre is a somewhat small basin for water. It has been cut through the brick pavement, and may therefore date back only to the Persian period and not to Nebuchadnezzar. An outflow channel led the water into the drain of the western passage; there are no signs of an inflow. The sides are constructed of upright bricks, and the inside is washed over first with asphalt and then with gypsum mortar. Gypsum decomposes in water, but only very slowly. When our Expedition House was built at Assur, the necessary reservoirs for water were made with gypsum mortar, and the gypsum wash on the walls, the roof, and balustrades of our house at Babylon has already lasted perfectly for twelve years. The basin corresponds with the indispensable “Hudeh” of modern Persian houses, in which everything employed for eating and drinking, and much besides, is washed. To the north lies a house of two courts (28 and 29) and one of four courts (30, 31, 32, and 33); the bureau that adjoins the first is connected with it by a door, while the two bureaus in front of the second house are only accessible from the court. In the north-east corner two parallel passages lead northwards. In one are the entrances to 28 and 29, in the other are those to the eastern houses. These open separately on to the passage, but the three northern houses are also connected with each other by doors, and it thus appears that they could be used if necessary either as separate dwellings or as one large one. This passage, like the one yet farther to the east, led to a door in the Citadel wall. In order to separate the two entrances to the Principal Court as completely as possible, the dividing wall is reinforced by an additional block that projects into the court.