Abstract: This invention generally provides an apparatus and a method for allowing the use of an existing handball court for playing both the game of handball and the game of squash. This invention includes an apparatus and method by which a rear squash wall is fixed at the appropriate location in an existing handball court for use during the play of squash. To then allow the play of handball, the rear squash wall is then detached, moved to the rear of the handball court, lifted to a position over the rear-end of the handball court and suspended behind and above the area of play used for handball. The reverse is performed to convert the handball court back for use for squash.

Abstract: The present bow thruster for water vessels comprises a submersible axial flow pumping unit mounted on the outside of the vessel at the bow to be raised to an inoperative position out of the water or lowered to an operative position in the water with its water-flow axis perpendicular to the longitudinal centerline of the vessel. The pumping unit is reversible, and it includes a hydraulic motor and a pump impeller inside an annular housing provided with gate valves at its opposite ends. The gate valve at the discharge end restricts the flow there to increase the thrust produced by the pump. A directional control and a fluid pressure source for the hydraulic motor in the submersible pumping unit are on board the vessel.

Abstract: The hydraulic turbine system includes:an electric generator;rotary turbine blades;a hydraulic pump for operation by rotation of the turbine blades;a hydraulic motor for driving the generator;a hydraulic reservoir;and connections between the pump, the motor and the reservoir for causing the motor to operate in response to rotation of the turbine blades by water flow.