The widest arch which has been found in any of the buildings is that of the Khorsabad town-gate uncovered by M.Place, which spans a space of (at most) fourteen or fifteen feet.

But the great halls of the Assyrian palaces have a width of twenty-five, thirty, and even forty feet.

It is at any rate uncertain whether the constructive skill of their architects could have grappled successfully with the difficulty of throwing a vault over so wide an interval as even the least of these.
M.Botta, after objecting, certainly with great force, to the theory of M.Flandin, proceeded to suggest a theory of his own.

After carefully reviewing all the circumstances, he gave it as his opinion that the Khorsabad building had been roofed throughout with a flat, earth-covered roofing of wood.

He observed that some of the buildings on the bas-reliefs had flat roofs, that flat roofs are still the fashion of the country, and that the debris within the chambers were exactly such as a roof of that kind would be likely, if destroyed by fire, to have produced.