Horse Power
the measure of a steam engine's power, as originally settled by James Watt, being a lifting power equal to 33,000 pounds raised one 33,000 000 pounds p raised one foot high per minute. Thus an engine is said to be of 100 horse power (h. p.) when it has a lifting capacity equivalent HORTENSE to 3,300,000 000 pounds one foot high per minute. To ascertain the horse power of an engine multiply together the pressure in pounds on a square inch of the piston, the area of the piston in inches, the length of the stroke in feet, and the number of strokes per minute, divide the result by 33,000, and the quotient, less one-tenth, allowed for loss by friction, for loss by will give the horse power. Engines are power.
Engines are frequently said to be of so many horse power nominal; the real or indicated horse power, however, often exceeds the nominal by as much as three to one.