Medieval devices used to hold down prisoners for torture (usually in torture chambers though they were also commonly found in town squares to discipline commoners). It was a wooden structure with three holes, two for hands and one for head/neck. It was hinged (the cut across half of the circles) and the prisoner's neck and arms would be placed in the semi-circles, then it would be closed and clamped shut. The stocks (base of the pillary) would be bolted to the ground so that the prisoner could not move and torture (commonly whipping) would be administered.