And yet there would, perhaps, have been room for hesitation had no support to this induction been afforded by the figured monuments; for the inhabitants of the province of Mossoul have deserted the traditions of their ancestors in more than one particular. They have given up the use of crude brick, for instance, so far, at least as the walls of their houses are concerned. They have supplied its place with stone and plaster, hence their dwellings are less fresh and cool than those of their fathers. In such a question the present throws a light upon the past, but the two have distinctive features of their own, even when the physical characteristics of the country have remained the same. The best evidence in favour of the employment of such an arrangement in Assyria is that of the bas-relief. We there not infrequently encounter an object like those figured on this page. Sometimes it is in the midst of what appears to be an entrenched camp, sometimes in a fortified city. Its general aspect, certain minor details, and sometimes an accompanying inscription, permit us to recognize in it the marquee or pavilion of the king.[213] Now the roofs of these structures evidently consist of two semi-domes, unequal in size and separated by an uncovered space. If such an arrangement was found convenient for a portable and temporary dwelling like a tent, why should it not have been applied to the permanent homes both of the king and his people? Arches still standing in the city gates, fragments of vaults found within the chambers of Sargon's palace at Khorsabad, the evidence of the bas-reliefs and the existing methods of building in Mesopotamia--all concur in persuading us that the vault played an important part in the constructions of Assyria, and consequently in those of Chaldaea; but we should not go so far as to say that all the rooms in the palace at Khorsabad and elsewhere were covered with barrel vaults, domes, or semi-domes. Our chosen guides, have, we think, allowed themselves to be a little too absolute in this particular; it is quite possible that by the side of the vaulted chambers there were others with wooden roofs. This conclusion is suggested partly by Sir H. Layard's discovery of considerable quantities of wood ashes in the palaces he excavated, partly by the evidence of ancient texts that wood was often used throughout this region to support the roofs at least of private houses. We may quote, in the first place, some remarks in Strabo's account of Susiana, which the Greek geographer borrowed from one of his original authorities: "In order to prevent the houses from becoming too hot, their roofs are covered with two cubits of earth, the weight of which compels them to make their dwellings long and narrow, because although they had only short beams, they had to have large rooms, so as to avoid being suffocated." This same writer, in speaking of these roofs, describes a singular property of the palm-tree beams.