Re: Horsepower (was Re: Metric Time (was Re: Why not 13 months? (Was La Systeme Metrique))

Oz (
Tue, 17 Oct 1995 19:08:21 GMT (A.J.Cribbin) wrote:

>The "horsepower" was based on an estimate of what a horse
>would be capable of achieving.
>Actually a horse has about 10 horsepower...

When I was taught this, the story was that it was the output
of a pit pony in Wales (or maybe Scotland). The reason for
the apparent low horsepower (if you see what I mean) was:

1) They were particularly small ponies as they went down the
mines too and the shafts and tunnels were small.

2) It was the average of a days work. A horse working
non-stop for 10 hours a day, day after day, will produce a
lower horsepower than one working for only a few hours. (At
least he will if he is sensible).

I would guess a large powerful shire horse, that only worked
at full power for a few months a year (and with weather
breaks) would indeed produce close to 10hp.

'Oz "When I knew little, all was certain. The more I learnt,
the less sure I was. Is this the uncertainty principle?"