On this latter point M.Botta and M.Flandin--both eye witnesses--were at variance.

M.Flandin believed that he had seen such traces, not only in numerous broken fragments of burnt brick strewn through all the chambers, but in occasional masses of brick-work contained in some of them actual portions, as he thought, of the original vaulting.

M.Botta, however, observed--first, that the quantity of baked brick within the chambers was quite insufficient for a vaulted roof; and, secondly, that the position of the masses of brickwork noticed by M.Flandin was always towards the sides, never towards the centres of the apartments; a clear proof that they had fallen from the upper part of the walls above the sculptures, and not from a ceiling covering the whole room.

He further observed that the quantity of charred wood and charcoal within the chambers, and the calcined appearance of all the slabs, were phenomena incompatible with any other theory than that of the destruction of the palace by the conflagration of a roof mainly of wood.
To these arguments of M.Botta may be added another from the improbability of the Assyrians being sufficiently advanced in architectural science to be able to construct an arch of the width necessary to cover some of the chambers.

The principle of the arch was, indeed, as will be hereafter shown, well known to the Assyrians, but hitherto we possess no proof that they were capable of applying it on a large scale.