[PLATE CIX., Fig.

3.] Often they possessed two or more _enceintes_, which in the bas-reliefs are represented one above the other; and in these cases the outermost circuit was sometimes a mere plain continuous wall, as in the illustration.

They were entered by large gateways, most commonly arched, and closed by two huge gates or doors, which completely filled up the aperture.

Occasionally, however, the gateways were square-headed, as in the illustration, where there occurs, moreover, a very curious ornamentation of the battlements.
[PLATE CX., Fig.

1.] [Illustration: PLATE 110] These fortified places the Assyrians attacked in three principal ways.
Sometimes they endeavored to take them by escalade, advancing for this purpose a number of long ladders against different parts of the walls, thus distracting the enemy's attention and seeking to find a weak point.
Up the ladders proceeded companies of spearmen and archers in combination, the spearmen invariably taking the lead, since their large shields afforded them a protection which archers advancing in file up a ladder could not have.