Rensselaer Semi-Weekly Republican, Volume 37, Number 6, Rensselaer, Jasper County, 20 January 1905 — WHAT HORSE POWER MEANS. [ARTICLE]

WHAT HORSE POWER MEANS.

Term Refers to Work Done by the Average Horse in a Minute. Wliat is the relative amount of work that a man can do in comparison with a horse or machinery? At his very host the strongest man stands In pretty poor comparison, even with a horse, for hard, continuous labor, lie might perform for a few minutes one-half horse power of work, but to keep this up for any great length of time would be impossible. Thus the gain in forcing horses to do a part of the world's work was enormous. One horse could exhaust a dozen men in a single day, and still be ready for the next day's work. The measurement of a horse’s power for work was first ascertained hv Watt, the father of the modern steam engine, and he expressed this in terms that hold to-day. He experimented with a great number of heavy brewery horses to satisfy himself that his unit of measurement For work was correct. After many trials lie ascertained that the average brewery horse was doing work equal to that required la raise 330 pounds of weight 100 feet high in one minute, or 33,000 pounds one foot in one minute. So he called this one horse power. This work, however, is not continuous, for the horse would have to hack tip after each pull to lower the line of the pulley, and thus ho would work four hours a day in pulling 330 pounds in the air at the pate of 100 leet a minute, and four hours in slacking up the rope. Consequently no horse can actually perform continuously what is generally called one-horse power. The horse was never born that could tug at a rope for eight hours a day, pulling 330 pounds 100 feet each minute without rest or change. Consequently, when we speak of horse power we refer only to the average work a horse cun do in one minute, that is to say, tlie rate at which lie can work. A strong man might pull half that weight 100 feet in the air in two min utes, hut lie could not repeat the operation many times without being exhausted. For all needful purposes the expression of one horse power is accurate enough nnd practically shows the measurement of an average horse’s abilities for working. Ab a rule a strong man can in eight hours work at the rate of about one-tenth of one horse power; that is, it would require ten men to 330 pounds 100 feet iu tlie air in a minute and then slack up and repeat the operation throughout the eight hours of n working day. The world's gnin in labor when horses were first employed to help man in bis work waa thua tenfold. —St. Nicholas.