Moat

A wet or dry ditch, dug round the walls of a town, or fortified place. When an enemy attacks a town, which has dry moats round it, the rampart must be approached by galleries under ground, which galleries are run beneath the moat; when the place is attempted through wet moats, your approaches must be made by galleries above ground, that is to say, by galleries raised above the surface of the water. The brink of the moat next the rampart is called the scarp, and the opposite one the counterscarp. Dry - Moat , that which has no water. It should invariably be deeper than the one that is full of water. Flat bottomed Moat , that which hath no sloping, its corners being somewhat rounded. Lined Moat , that whose scarp and counterscarp are cased with a wall of mason work made aslope.