Abstract: A hydraulic fluid injection apparatus is described that has a container that has a chamber with a first, second and return means section. There are two pistons with a seal means on each piston and the two pistons are connected by a rod. Input fluid pressure by a pressurized first fluid, such as water, on the first piston causes the second piston to move and pressurize a second fluid, such as an insecticide, out of the second section and into a mixing line, through a calibrated metering means and into an output fluid line to be joined by the first fluid arriving from the first section of the chamber. There is a mixing means in the output fluid line to mix the two fluids more thoroughly. There is a return means in the return means section of the chamber that returns the second piston to a lower position when the pressure on the first piston is less than the return force of the return means and allows the second section to be refilled as necessary.

Abstract: A device for mixing methyl methacrylate monomer and methyl methacrylate polymer to form bone cement in a hospital operating room includes a bowl-shaped container, a replaceable resilient plastic bowl-shaped liner which fits in the bowl-shaped container, a fluid passageway formed between the liner and container and a deflector cap which covers the space between the upper end of the liner and the upper end of the container. Exhaust openings in the side wall of the liner place the interior of the liner in fluid flow communication with the fluid passageway. The methyl methacrylate monomer and polymer are mixed in the bowl-shaped liner.