C. J. Gadd, The Stones of Assyria, Pl. 4

Wielding a knife, an Assyrian soldier, lower center, literally cuts off the water supply of the besieged city by slicing through a rope attached to a bucket, which the defenders apparently lowered from the wall to draw water from a cistern. Cutting off a city’s water supply, by this or by other, more permanent techniques, could effectively force a city to surrender. This relief originally decorated the Northwest Palace of Ashurnasirpal II, but Tiglath-pileser III (744–727 B.C.) had it removed for reuse in his Southwest Palace, where the British excavator Austen Henry Layard discovered it.