Liquid control system

A liquid source system for supplying sterile liquid to a surgical tool comprising a flexible, inelastic vessel containing said sterile liquid, conduit means connecting said vessel to said tool, pressurizing means including a stationary first wall and a stationary second wall generally parallel to said first wall, a plate slidingly mounted between and generally parallel to said first and second walls, to define a vessel receiving zone adapted to receive said flexible, inelastic vessel between said plate and said first wall, and gas activatable cylinder means for urging said plate toward and away from said first wall when said flexible vessel is disposed within the vessel receiving zone, said gas activatable cylinder being connected by activating gas conduit means to sensor means adapted to sense exhaust gas from said tool and provide activating gas to said cylinder whereby liquid is supplied to said tool concurrently with drive gas, said sensor means comprising a low pressure amplifier having an inlet connected to exhaust conduit means from said tool, an amplifying gas inlet connected to an amplifying gas source and an amplifying gas outlet connected to an amplifying gas inlet of a high pressure amplifier having an activating gas inlet connected to an activating gas source and an activating gas outlet connected to said urging means.