The cylinder, in which a well-fitting piston worked, was provided at its lower end with two valves.
In a particular case where the boiler pressure was maintained constant at 130 lb per square inch, and the cut-off was approximately 20% of the stroke, the values c =55 and b=o 031 were deduced, from which it will be found that the value of the piston speed corresponding to the maximum horsepower is 887 ft.
On again F J J raising the piston the valve E opens ?g G admitting more liquid whilst F re- mains closed.
The piston rod passes through a valve in the upper part of the cylinder which is held to its seat by a spring.
The total upward pressure on this piston is calculated to be equal to 150,000 lb; hence the shaft-bearings are practically relieved from pressure when the wheels are running.