The pressure is given by a set of hydraulic pumps made of crucible cast steel and bored out of the solid. One of the pump rams is 2½ in. diameter, and has a stroke of 7 in. This ram gives only a limited pressure, and the arrangements are such as to obtain this pressure upon each press in about fourteen seconds. This pump then automatically ceases running, and the work is taken up by a second plunger, having a ram 1 in. diameter and stroke of 7 in., the second pump continuing its work until a gross pressure of two tons per square inch is attained, which is the maximum, and is arrived at in less than two minutes. For shutting off the communication between the presses, the stop valves are so arranged that either press may be let down, or set to work without in the smallest degree affecting the other. The oil from the presses is caught in an oil tank behind, from which an oil pump, worked by an eccentric, forces it in any desired direction.

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