EFFECTIVE PRESSURE OF STEAM ON PISTON.

With different rates of expansion, boiler pressure

being assumed as 100 lbs. per square inch.

Steam cut off at ¾ of stroke = 90 lbs. effective pressure.

“ “ “ ⅔ “ “ = 80 “ “ “

“ “ “ ½ “ “ = 69 “ “ “

“ “ “ ⅓ “ “ = 50 “ “ “

“ “ “ ¼ “ “ = 40 “ “ “