Why, when the only horses most of us see are on old TV shows – why do we still measure the power of their replacements in horsepower? Even in the newest, computerized, teched-out cars – horsepower is the measure of engine power. In fact, some of our boss-est cars, iconic muscle cars like the Ford Mustang or Dodge Charger – are NAMED after the horse.
Ok, maybe we’re just old-school that way. But you’re curious now, right? What IS horsepower? Is it REALLY how many horses equal a particular car/engine?
And, actually, yeah – kind of, it is.
Originally, horsepower was invented to have a standard measure of how much work a horse could do. Back in the late 1600s – after some thought, and some rigging up a pulley and weights – a group of French scientists found that a horse could lift 165 pounds, a little more than 3 feet in the air, in one second. And since that was a job that took seven men to do – one horsepower equaled seven men.
About hundred years later, James Watt (the Scottish engineer, and yes, THAT “watt”) used horsepower to measure how much work the new steam engine could do. And that use of horsepower to measure engine power, has stuck ever since.
So today, if you were choosing between, say the 2018 Mustang, or horses – by that standard you’d need a pretty big garage (ok, technically, a stable) if you go the four-legged route, because the Mustang checks in at 460 hp.
Not to mention that even if you’re not driving a Mustang, the cost of filling up your car is a lot less than your annual bill for hay would be. Oh, and cleaning up after your ride? That’s definitely a plus for driving a car.
So let’s say a thank you to James Watt, for letting us use horsepower to measure the work our internal combustion engine-powered car is doing. And let’s save the real horsepower for a night of old Westerns – or watching Sherlock Holmes clatter through the streets of London in a horse-drawn cab.