iSo A HISTORY OF ART IN CHALD/EA AND ASSYRIA. domes or the timber ceilings by which they were supported. On the left of the engraving semicircular vaults are shown, on the rieht a timbered roof. The arrangement of the latter is taken o *-5 from an Etruscan tomb at Corneto, where, however, it is carried out in stone. 1 A frame like this could be put together on the spot and offered the means of covering a wider space with the same materials than could be roofed in by a horizontal arrangement. Further back rises one of those domes over square substructures w'. lose existence seems to us so probable. Behind this again opens one of the courts by which so much of the area of the palace was occupied. The composition is completed by a wall with parapet and flanking towers. FIG. 59. Fortress ; from Layard's Monuments, 1st Series. After considering the method employed for roofing the palace apartments, we come naturally to investigate their system of illumination. In view of the extravagant thickness of their walls it is difficult to believe that they made use of such openings as we should call windows. The small loop-heles that appear in some of the bas-reliefs near the summits of towers and fortified walls were mere embrasures, for the purpose of admitting a little air and light to the narrow chambers within which the defenders could find shelter from the missiles of an enemy and could store their own arms and engines of war (see Fig. 59). The walls of Khorsabad even now are everywhere at least ten feet high, and in 1 Gailhalaiid, Monuments anciens et modernes, vol. i. ; plate entitled Tombeaux superposes a Corneto.
