164

MODERN STEAM PRACTICE.

valve gear, the middle one for the equilibrium, and the bottom shaftfor the exhaust-valve gear. An arm is keyed on each shaft, havinga connecting rod coupled to the lever for lifting each valve; eachshaft has also an arm with a connecting rod passing downwards toa loaded lever, the weight of which lifts each valve respectively.

_ ~EqiäJ£b-rOLOTV shut

Fig. 101.—Cornish Valve Gear.

The valves are shut with tappets placed on the vertical rod workedby the engine, and named the plug rod; the tappets act on slide