[1507]. Auxiliary valve and bellows for air, as sometimes used in large organs to open heavy “pallets.” The small valve A is opened by the pressure of the finger on the corresponding key of keyboard, and allows the pressure of air to enter the small bellows which operates the large valve B.

[1508]. Four plunger valve, used for double power hydraulic lift cylinders employing a trunk piston. For the low power the pressure water acts on both sides of the piston; for the double power it acts only on the back of piston, the front side being then open to the exhaust.

[1509]. A starting valve, having two ordinary wing or spindle valves, either of which is lifted by a double cam or wiper on a spindle passing through a stuffing box on side of valve case. A supply, B cylinder port, C exhaust.

[Larger plate.]

[1510] & [1511]. Two methods of operating starting valves for hydraulic lifting machines. 1510 acts by counter balance weights and a single rope, each of the weights being heavy enough to move the valve, and 1511 by an endless rope.

[1512]. Low pressure starting valve, used for piston hydraulic cylinders in which the lifting is performed by the down stroke of the piston rod, and in lowering, the valve allows the water to pass from above to below the piston, the water being exhausted from below the piston on its down stroke when the valve is in the position shown.

[1513]. Oscillating valve, with plunger face kept up by a spring. The oscillating valve has two ports passing out at opposite ends, through stuffing boxes, to either end of the cylinder; the inlet is at top and discharge at bottom.

[1514]. Balanced self-acting starting valve, suitable for large machines and low pressure. The upper piston is larger than the lower or main piston, and the space above the upper piston can be put in communication with the pressure water below it, or the exhaust port by the small piston valve at top operated by the hand gear; so that the main piston is operated by the pressure water acting on it.