A pumping apparatus for harvesting the wave energy and converting such energy into hydraulic power which may be transmitted and used to generate electricity or to produce desalinated water. The pumping apparatus has a float, an accumulator pressurized above the ambient pressure of the pump, the accumulator is charged with fluid and the pump is full of fluid. A check valve is closed and a pumping chamber is pressurized. An additional pumping chamber is also equally pressurized. An axial force is generated on a first tube by the pressure difference between its ends. An opposite axial force is generated on a second tube by the pressure difference between its ends. The second tube is larger in diameter than the first tube and hence the magnitude of the force on the second tube is greater. The resultant of these forces is balanced by a portion of the buoyancy of float.