The Horse   

The wager was decided by Eadweard Muybridge at the request of Leland Stanford.
 

Muybridge was a colourful character best remembered as a motion picture pioneer. He was born in Kingston-on-Thames, England, where he was educated. After emigrating to the U.S., he became a photographer for the Coast and Geodetic Survey. In the 1870's he demonstrated by photographs that when a horse gallops, there is a moment when all of the animal's feet are off the ground.
Stanford apparently lost his bet, but that's not the last we hear of Muybridge...
 
Muybridge's photographs were made by an array of plate cameras activated in sequence by trip wires.
One sixteen shot sequence is reproduced above, and turning these into a movie or animation is relatively easy for something like the Mac -
but there are subtleties...
(Please note that the animation is large and the 260kB file may need some time to download completely.
It does come up in a separate window, however.)
 
Photo above reproduced from "Physics World" (IoP, London), April 1998 issue, p.43.
 

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