JF Ptak Science Books Post 797 (Sept 2009) Extended.
In 1702, at the beginnings of the Industrial Revolution, Thomas Savery (c.1650 - 1715) began the idea of calculating the work done by steam engines over that done by horses, writing in his book, The Miner's Friend:
"So that an engine which will raise as much water as two horses, working together at one time in such a work, can do, and for which there must be constantly kept ten or twelve horses for doing the same. Then I say, such an engine may be made large enough to do the work required in employing eight, ten, fifteen, or twenty horses to be constantly maintained and kept for doing such a work…" But it was James Watt who first introduced the term ”horsepower” while trying to advertise and place forever the idea of his steam engine over than of the earlier Newcombe engine and, of course, horses.”
James Watt (1736-1819), Scottish inventor and “re-inventor” of the steam engine, the man who put the ‘power” into “horsepower”, determined that a horse could turn a mill wheel (of a 12-foot radius) about 144 times in an hour (about 2 ½ times a minute), traveling 2.5x2pix12 per minute. It has been shown though that on average a horse will work at about 1.5 horsepower like this for an hour on and off; and less than 1 horse in other times; a man could work at 1.5-2.5 horsepower for a short time, but generally would pull about a tenth of that for an extended time.
And so we come to the crux of the biscuit of this post: a dog motor. This entirely, utterly, unconvincing and thoroughly bad idea was fully fleshed out by a M. Richard (naturally of Paris) for the Agricultural Exhibition and re-published from La Nature in the Scientific American Supplement on 10 August 1895. It is slightly lovely in its high Victorian way, or at least so until you consider that an animal goes in side the thing, working its way along an infinite belt, a cup of water just within reach. The dog would power the large wheel, which would turn a smaller wheel and belt, which in turn would be connected to smaller, and so on, until it reached whatever it was it was powering, which is left entirely to our imagination. Even when I squeeze my eyes in a telescoping effort, I cannot see what it is that this poor doggie might power. Given the descending orders of radii of the wheelworks, perhaps the tenth-horsepower dog engine ran a fan, or something, something remarkably insignificant. It does tell us something about over-design, like buying a ten dollar bill with a twenty.
Another, more recent but less serious attempt at utilizing canine power was found in Popular Science for 1939:
The thing that really bothers me is that both of these really bad ideas occurred in years where there were fantastic ideas in the history of physics--1895 being the home to the discovery of the atomic world in the work of Wilhelm Roentgen, and 1939, well, more of the same plus making the atomic world go "boom".
In this same vein, and keeping with the highlight-year-for-physics theme, is this thing, created in the 1880's but published in Popular Science in 1933:
With the help of Laura Massey (Bookn3rd !), from the wonderful bookseller blog, The Cataloguer's Desk at the great Peter Harrington Rare Book Shop (London), I'm including an 18th century version of sweating dogpower called the Turnspit:
I'm not sure what it is that would keep the dog running after it realized in the first half-minute that it will never be able to retrieve that hanging thing set out in front of him/her--maybe things got poke-y.
More useful to run it reverse as a dog-walking machine.
Posted by: Ray Girvan | 23 September 2009 at 08:42 AM
True. Or you could just go for a walk with the pooch.
Posted by: John Ptak | 23 September 2009 at 09:13 PM