Abstract: An improved air compressor powered by water having an automatic water valve regulation mechanism. The air compressor includes a resiliently biased piston within a liquid chamber and a ram within a compression chamber, the ram being conjoined with the piston. Inlet and outlet valves for controlling the flow of water with respect to the liquid chamber are provided in one end of the compressor. Ports for the inlet and outlet valves are preferably aligned parallel to the axis of piston reciprocation such that water flows through the ports in the same direction as the direction of piston movement. The automatic valve regulation mechanism includes a positioning disc and positioning spring, together holding each of the water valves in one of two positions.

Abstract: A cap for an aerosol container comprising an annular wall open at its bottom end and closed at its upper end by a top wall, one of the walls having retaining devices for releasably retaining a tube within said one wall whereby when the tube is releasably retained within the one wall, an aperture surrounds the tube and upon applying a predetermined force to the tube, the retaining devices release the tube so that the tube is capable of being completely removed from the aperture. The cap may include a second aperture spaced from the first mentioned aperture and guiding devices for guiding an advancing end of the tube toward the second aperture.