Fig. 2. Arch construction. (From Ocheïdir, by kind permission of Dr. Reuther.)
The great hall, to the south of room 4, is the largest chamber in the palace. It is 15·50 metres long by 7 metres wide, but its width is increased on either side by arched recesses 1·40 metres deep and from 2·20 metres to 2·30 metres wide ([Plate 14], Fig. 1). These recesses, five on either side, are separated from one another by squat engaged columns set against piers which are ·80 metre deep. The columns carry rectangular impost-capitals from which spring the shallow slightly pointed semi-domes, or calottes, which cover the recesses. The capitals are very roughly constructed of small stones. There are traces of a shallow abacus, while a cavetto moulded in plaster seems to have been interposed between capital and shaft. At the corners a triangular stone adjusted the circle of the column to the square of the abacus, and the whole was no doubt covered with plaster. The abacus projection runs back along the walls of the niche and above it the calotte springs from another small projection ([Plate 15], Figs. 1 and 2). The calottes are bracketed over the angles, the construction being the same as that described in the dome of room 4. All the niches of Ukhaiḍir are treated in like fashion. The method employed in constructing the archivolts is admirably described by Dr. Reuther.[17] The face of the arch is formed by a permanent centering composed of gypsum and reeds. The vaulting takes place, not above the centering but between the two centering arches, the vault being built in vertical rings ([Fig. 2]). When the arches are of wide span an outer ring of horizontal voussoirs is added to the inner arch. This system is common in Mesopotamia to the present day, and is found frequently at Ukhaiḍir. In the great hall there are holes for wooden beams below the abacus of the capitals and in the spandrels of the arches. The northern recess on the east side is open and gives access to a ramp which leads to the first floor. The second, third, and fifth recesses contain low doors covered by a segmental arch. On the west side similar doors are set in the first, third, fourth, and fifth recesses, the last named giving access to a stair ([Plate 15], Fig. 2). The calotte archivolts at their highest point are 3·50 metres above the present level of the floor. The wall is carried up for another 1·25 metres, where there is a double outset from its face. Above this outset the stone vault runs up perpendicularly for about ·80 metre and the remainder of the vault is of brick ([Plate 14], Fig. 2). For a height of about 1·50 metres the brick tiles are laid horizontally, but when the curve of the vault increases the bricks are set upright in vertical rings. The vault thus formed is built without centering; it has a slightly pointed, ovoid shape and is much stilted. The north wall remains intact and its scheme of decoration is instructive ([Plate 16], Fig. 1). The arched door, 3·50 metres high, is set back within a niche 1 metre deep. About ·90 metre above the arch of the door stands a very shallow calotte covering the niche. The face of the calotte is recessed, which enhances its decorative value by giving it a double outline. As Dr. Reuther has observed,[18] the calotte is not ‘the segment of a pointed dome, but its curve in horizontal section springs sharply back from the face of the archivolt and flattens rapidly behind. Thereby the effect of the shadow is strongly felt at the edge, and the calotte seems to be deeper and more markedly vaulted than it is in reality’. At the base of the calotte there is a small niche which has been broken through owing to the partial ruin of the dome behind it.[19] In the wall on either side of the calotte there is a shallow arched niche. The arch is carried on pairs of engaged columns and is enclosed in a rectangular label. Above the calotte are the three windows of the first floor room, 88, covered by segmental arches. The windows are framed by engaged columns which carry stilted round-arched calottes. The south wall of the great hall is partly ruined. The doorway seems to have been of the same proportions as the door in the north wall, but it was not set back within a niche. The small decorative niches reappear on either side, and there were probably three windows opening into room 101 in the upper story, indeed on the west side the window jamb can still be seen. Even with these windows the great hall must have been most insufficiently lighted, since neither its doors nor its windows open directly on to the exterior of the building. To the south lay the small rectangular chamber, No. 27, which was probably, as Dr. Reuther suggests, covered by a dome similar to the dome of No. 4. It opens to east and west into the vaulted corridor 28, and on the south into the central court.
Holes for wooden beams can be seen on the north wall of the great hall, two on either side of the portal niche, one on either side of the shallow decorative niches, and one on either side of the group of windows. On the south wall they have been somewhat differently disposed, one on either side of the door at the level of the arch, one almost immediately above, higher than the top of the arch, and three higher up still, following the curve of the vault ([Plate 14], Fig. 2).
The masses of masonry on either side of the vault are lightened by the tubes which are characteristic of the vaulting system of Ukhaiḍir (section a-b, Plate 4, Fig. 1). One of these tubes pierces the wall on either side, partly above the calottes of the recesses. On the east side the opening of this tube can be seen high up in the wall of the corridor 28; on the west side the tube is not visible owing to the interposition of a stair behind the corridor, but there can be no doubt that it exists. Again towards the top of the vault there is another pair of tubes. The western of these two can be seen through a breach in the wall of the stair which leads from room 89 to the second floor; I infer its eastern counterpart. The vault of the great hall is buttressed by the vaults of the chambers of the ground floor and of the first floor which lie at right angles to it.
The wings of the three-storied block, of which the great hall forms the centre, are bounded to the north by the two vaulted corridors 5 and 6 ([Plate 17], Fig. 1), the western corridor, 5, being 34 metres long, and the eastern, 6, 34·90 metres long. The vaults are constructed in the usual fashion, oversailing the wall and built of thin slabs of stone, laid vertically in concentric, slightly pointed rings. The corridors lead into the palace yard. The door of the west corridor is much ruined. The door of the east corridor is set in a niche surmounted by a shallow calotte, of which the archivolt is slightly pointed. Below the calotte, between it and the arch of the door, is a second small arched niche, connected by the usual funnel with the top of the door arch. The calotte is outlined by a singular decoration composed of a crenellated motive.[20] The crenellated motive is common in the ornament of Ukhaiḍir and elsewhere, but I am not acquainted with any other example of its application to the archivolt.
To the south of the east corridor runs a vaulted ramp, a sloping passage from the great hall to the first floor. To the south of the ramp lie two groups of three vaulted chambers. In the inner group, Nos. 12, 13, and 14, the rooms are 7 metres long with an average width of 3·50 metres. They are separated from each other by walls 1 metre thick, and communicate with each other by doors covered by ovoid arches set back from the jambs. Each room possesses a door into the great hall, but since the position of these doors is determined by that of the recesses in the hall, which do not correspond with the rooms behind them, the doors are never in the centre of the rooms, and in one case, No. 13, the side wall is narrowed to allow space for the door. The wall which separates the rooms from the recesses of the great hall is 1·50 metres thick. A door at the east end of each room leads into the corresponding room of the second group. In this group the rooms 15, 16, and 17, while they have the same width as those of the first group, are considerably shorter, measuring only 4·80 metres. They communicate with each other and with the vaulted passage, 20. Room 17 has further a door in the north wall, which leads into the small vaulted room, No. 18, and this in turn is connected with a still smaller room, No. 19. Nos. 18 and 19 lie under the ramp, and No. 19 is in consequence extremely low. None of the chambers above described are provided with windows; what light they possess filters in through the doors. Nos. 12, 13, and 14 are therefore exceedingly dark, and must have been darker still when the south wall of the great hall was intact. Nos. 18 and 19 are totally unillumined, and for this reason, and on account of the inconvenience of their low vaults, it may be presumed that they were not used for dwelling purposes.