The first difficulty which presented itself here was one of those regarded as most fatal to the vaulting theory, namely, the width of the chambers. Where flat timber roofs prevail in the East, their span seems never to exceed twenty-five feet. The ordinary chambers in the Assyrian palaces might, undoubtedly, therefore, have been roofed in this way, by a series of horizontal beans laid across them from side to side, with the ends resting upon the tops of the side walls. But the great halls seemed too wide to have borne such a roofing without supports. Accordingly, M. Botts suggested that in the greater apartments a single or a double row of pillars ran down the middle, reaching to the roof and sustaining it. His theory was afterwards warmly embraced by Mr. Fergusson, who endeavored to point out the exact position of the pillars in the three great halls of Sargon at Khorsabad. It seems, however, a strong and almost a fatal objection to this theory, that no bases of pillars have been found within the apartments, nor any marks on the brick floors of such bases or of the pressure of the pillars. M. Botta states that he made a careful search for bases, or for marks of pillars, on the pavement of the north-east hall (No. VIII.) at Khorsabad, but that he _entirely failed to discover any_. This negative evidence is the more noticeable as stone pillar-bases have been found in wide doorways, where they would have been less necessary than in the chambers, as pillars in doorways could have had but little weight to sustain. M. Botta and Mr. Fergusson, who both suppose that in an Assyrian palace the entire edifice was roofed in, and only the courts left open to the sky, suggest two very different modes by which the buildings may have been lighted. M. Botta brings light in from the roof by means of wooden _louvres_, such as are still employed for the purpose in Armenia and parts of India, whereof he gives the representation which is reproduced. [PLATE XLVII., Fig. 7.] Mr. Fergusson introduces light from the sides, by supposing that the roof did not rest directly on the walls, but on rows of wooden pillars placed along the edge of the walls both internally towards the apartments and externally towards the outer air. The only ground for this supposition, which is of a very startling character, seems to be the occurrence in a single bas-relief, representing a city in Armenia, of what is regarded as a similar arrangement. But it must be noted that the lower portion of the building, represented opposite, bears no resemblance at all to the same part of an Assyrian palace, since in it perpendicular lines prevail, whereas, in the Assyrian palaces, the lower hues were almost wholly horizontal; and that it is not even Certain that the upper portion, where the pillars occur, is an arrangement for admitting light, since it may be merely an ornamentation.