Horse in Motion

It may come as a surprise in the twenty-first century to discover that, in the 1880s, details of how objects move were unknown. The human eye, unaided, cannot resolve the details of fast motion. Eadweard Muybridge and his experiments with motion photography, such as this series of pictures of a horse's gait, helped solve this mystery.

From https://sites.utexas.edu/ransomcentermagazine/2013/05/22/eadweard-muybridge/ - edited

Muybridge's solution

The Man Who Stopped Time

Photographer Eadweard Muybridge stunned the world when he caught a horse in the act of flying.

By Mitchell Leslie

On a bright, balmy morning in June of 1878, a crowd of racing enthusiasts and newspapermen huddled beside the track on the Palo Alto Stock Farm, waiting to see a horse run. Leland Stanford had invited them to his estate and horse-training mecca to witness a photographic first.

The nation was swept up in a technological explosion. Americans swooned over inventions like the telephone and phonograph, while Edison prepared to unveil the lightbulb and Eastman set his sights on a handheld box camera. Having served his term as governor and launched a railroad empire, Leland Stanford was savoring life as a country gentleman.

Horses were his passion. For him, the racetrack demonstration would culminate five years of experiments, undertaken with photographer Eadweard Muybridge, to clinch a pet theory about equine gait. Is a running horse ever completely aloft? Stanford insisted the answer was yes.

Stanford and Muybridge opened the day's spectacle by showing off their meticulous preparations. On one side of the track stood a whitewashed shed, with an opening at waist level across the front. Peeking out were a dozen bulky cameras, lined up like cannons in a galleon. On the opposite side, a sloping white backdrop had been raised to maximize contrast. The show began as one of Stanford's prize trotters, driven by master trainer Charles Marvin, sped down the track pulling a two-wheeled cart called a sulky. Across the horse's path were 12 wires, each connected to a different camera. When a sulky wheel rolled over one of the wires, it completed an electrical circuit, tripping the shutter of the attached camera. The shutters firing in quick succession sounded like a drumroll.

A single exposure could take minutes in those days, but the state-of-the-art cameras managed all 12 shots in less than half a second. Within 20 minutes, Muybridge had developed the plates and laid out the results for the visitors to admire. The series made a brief filmstrip of the horse's progress along the track--capturing, for the first time, ephemeral details the eye couldn't pick out at such speeds, such as the position of the legs and the angle of the tail. Stanford got the evidence he wanted, and the world got a stunning dissection of motion. "It was a brilliant success," one reporter wrote. "Even the threadlike tip of Mr. Marvin's whip was plainly seen in each negative, and the horse was exactly pictured."

https://alumni.stanford.edu/get/page/magazine/article/?article_id=39117

You can find a very detailed graphic description on the next page.