Trees, too, were sometimes cut down and built into the mound.
Besides battering-rams, the Assyrians appear to have been acquainted with an engine resembling the catapult, or rather the _balista_ of the Romans.

[PLATE CXI., Fig.

1.] This engine, which was of great height, and threw stones of a large size, was protected, like the ram, by a framework, apparently of wood, covered with canvas, felt, or hides.

The stones thrown from the engine were of irregular shape, and it was able to discharge several at the same time.

The besiegers worked it from a mound or inclined plane, which enabled them to send their missiles to the top of the ramparts.