Hydraulic tourniquet, also called Barker's mill. It consists of a vessel of water free to rotate about a vertical axis, and having at its lower end bent arms through which the water is discharged horizontally, the direction of discharge being nearly at right angles to a line joining the discharging orifice to the axis. The unbalanced pressures at the bends of the tube, opposite to the openings, cause the apparatus to revolve in the opposite direction to the issuing liquid.

Tourniquet

Hydraulic tourniquet, also called Barker's mill. It consists of a vessel of water free to rotate about…