When a horse is running or trotting, do all four hooves ever leave the ground at the same time? That was the wager that the former Governor of California, Leland Stanford had with some of his friends. There was much controversy in horse racing circles at the time, and though most people believed that a horse always has one hoof in contact with the ground, Stanford thought otherwise. Because a horse's legs are moving so fast, it's impossible to tell just by looking, so he needed a way to slow down the movement so it could be studied.



In most 19th century cameras, a picture was taken when the photographer removed the lens cap for several seconds in order to expose the film and capture an image. The subject had to remain perfectly still during this time or the resulting photograph would be blurred. In order to capture very fast action like a galloping horse, the exposure time would have to be very short. Muybridge invented a fast shutter mechanism that relied on a small piece of wood with a hole drilled in it that slid past the lens. The wood was positioned such that a pin held it in place covering the lens. When the pin was removed, gravity would cause the wood to drop and as the hole moved past the lens, the film was exposed for a fraction of a second.



Muybridge first tried taking a single photograph as a horse ran by, but he had a difficult time getting any image. He tried various methods of making the shutter move faster and faster so as to shorten the exposure time, and as he did the quality of the image began to improve. Finally he hit upon the idea of using two pieces of wood and slipping them past each other so quickly that he had achieved an exposure time of about one five hundredth of a second. That solved the problem of capturing a reasonably clear image of a horse at a gallop, but it still didn't provide him with a way to settle the bet.



In 1874, his work was interrupted when he shot and killed his wife's lover, whom he suspected was actually the father of a male child his wife had born earlier that year. He was imprisoned until his trial in February 1875. At the trial he was acquitted, thanks to the lawyer that Stanford had hired for him, but afterwards he decided to leave the country for a while and did not continue the experiments until his return to California in 1877. He then continued his work on increasing the shutter speed until he had reduced the exposure time to less than 1/2000th of a second.



Once Muybridge was satisfied with the quality of the images, he had to figure out a way to capture several images in sequence. He decided to place several cameras in a row all pointing in the same direction and trigger them in sequence as the horse galloped past. He attached strings to all the shutters on all the cameras and stretched them across a track, so that as the horse passed by touching each string in turn, the cameras would take their pictures one at a time and in sequence.



In 1878, after many experiments during which he made further refinements to the triggering mechanism and improvements in the sensitivity of emulsion paper, he succeeded in achieving the results he needed to settle the bet and collect the $25,000. He had a sequence of 12 images, and one of them clearly showed that all four of the horse's hooves were off the ground at the same time. It was the first successful photographic representation of a sequence of movement and it made him an international star.

Muybridge's first picture sequence In 1879 he invented the Zoopraxiscope, a device with counter-rotating discs that projected the images sequentially. Now one could actually see a representation of the horse galloping and the effect was truly stunning. After a public showing in San Francisco a reporter gushed, "Nothing was wanting, but the clatter of hoofs upon the turf and the occasional breath of steam to make the spectator believe he had before him the flesh and blood steeds."

Zoopraxiscope He continued his experiments using more cameras and photographing the motions of other animals and later did extensive studies of human movement. He eventually published his photographs in a portfolio called Animal Locomotion (1887) and two books; Animals in Motion (1899) and The Human Figure in Motion (1901). The latter created quite a stir at the time for it's use of nude male and female models.



Though Thomas Edison is usually credited with creating the first movies in 1889, it was the work of Eadweard Muybridge, and a $25,000 bet that provided the cornerstone of Edison's invention and the evolution of motion pictures.

