Windows, which to our idea form one of the most important parts of a building, were apparently taken into little account by the Babylonians and Assyrians. In the case of one-storied buildings the only windows seem to have been skylights. At all events Place discovered terra-cotta cylinders in several of the rooms at Khorsabad, which according to him, must have formed a part of the roof through which air and a modicum of light was admitted into the chamber. The buildings represented on the bas-reliefs are indeed provided with small openings, but these appear to be embrasures rather than windows properly so-called. But in any case, even if windows were cut in the walls, the extreme thickness of the latter would have excluded nearly all light. THE COLUMN The column never seems to have occupied a prominent position in the history of Mesopotamian architecture, a fact which was again due to the dearth of stone and wood; there is however sufficient evidence to prove that it was certainly not unknown, though it was not very frequently employed. In modern architecture the column forms the main support of arches, but in Babylonian and Assyrian architecture the archivolts and pendentives of the arch are generally supported by thick walls; this fact is testified to alike by the remains of ancient buildings and also by the figured representations of such buildings found on the bas-reliefs. Probably the best examples of an early Babylonian column are those discovered by De Sarzec at Tellô in 1881, though strictly speaking they are not columns, but piers formed by the union of four circular columns (cf. Fig. 12). The piers are composed of circular, semicircular, or triangular bricks, which bear an inscription, from which we gather that the new construction of which they presumably formed a part was largely made of cedar-wood, a statement confirmed by the discovery of fragments of this wood amid the ruins. [Illustration: FIG. 12. (Cf. _Déc. en Chald._, Pl 53, 2.)]