The means of tapping underground water or springs (Gen. 21: 25). Because water was sometimes scarce, wells, artificially dug, were extremely important and often fiercely fought over for possession. They could also be in the form of deep cisterns for storing water or even immuring prisoners (Jer. 38: 6). The top of wells might be covered by a circular stone (Gen. 29: 2; Exod. 21: 33) and the water drawn up by means of a vessel attached to a rope.