THE photographer took off his clothes.

With his curly white beard, he looked like a well-muscled Moses, as he posed before the 36 cameras.

He picked up the discus, coiled himself up, then threw, as the cameras clicked in sequence.

And so, with the help of his assistants, photographer Eadweard Muybridge himself became one of the 781 selections in his monumental series, "Animal Locomotion."

Owning almost all of the plates, the Corcoran Gallery of Art is displaying a minuscule sampling of 48 of them in "Eadweard Muybridge: Extraordinary Motion." Each collotype plate has at least a dozen photos, isolating instances of locomotion too quick for the eye. Although Muybridge photographed birds and animals as well, the Corcoran has chosen to exhibit photos of people from "Animal Locomotion," and to contrast "normal" with "abnormal" -- for example, juxtaposing two series of men walking, one with average gait, one with epilepsy.

For the modern viewer, Muybridge's locomotion studies belong in the same class as old black-and-white stereoscopic views; they're quaint and historically interesting. But this was heady stuff back in 1887, when Muybridge offered for sale a selection of a hundred plates for a hundred dollars; $600 for the lot.

Fifteen years before, Muybridge had startled the world with his finding that when a horse gallops, all four hooves leave the ground at one point. His concept of recording the process of locomotion grew into a personal obsession and fortunately for him, the University of Pennsylvania was willing to finance his encyclopedic effort. Such pinpointing of the nuances of muscle movement was vital to some artists. And, before the invention of the X-ray machine, doctors saw locomotion studies as useful in diagnosing diseases and their effects.

Known only by number, Muybridge's anonymous subjects were usually photographed nude, to show anatomy. Among the selections in his photographic project, Muybridge labeled only 23 as "abnormal." These photos were taken mainly at the Blockley Hospital for the Poor in Philadelphia and include a child with polio who, touchingly, smiles at the camera as he crawls. (In the show, photos of the child contrast with photos of a "normal" woman walking on all fours; the child appears the more graceful.) Others not classified "abnormal" -- a contortionist and a 340-pound woman, hardly run-of-the-mill types -- would have enthralled a Diane Arbus.

One result of Muybridge's concentrated effort was that artists exposed to his photos changed the way they depicted movement.

Muybridge was born Edward James Muggeridge, in Kingston-upon-Thames, in England, in 1830. An eccentric from the start, he changed the spelling of his first name to Eadweard, after two 10th-century Saxon kings whose names were engraved on a coronation stone there. Coming to America in 1852, he settled in San Francisco as a book dealer, and changed his last name to Muybridge. After a disastrous fall from a stagecoach, he took up photography, probably as therapy, when a doctor recommended he spend more time outdoors.

Besides his forward steps in locomotion, Muybridge invented the "zoopraxiscope," which projected his photographs, mounted on glass disks, onto a screen, producing an early ancestor of the motion picture.

He also photographed Yosemite landscapes long before Ansel Adams was born. EADWEARD MUYBRIDGE: EXTRAORDINARY MOTION -- At the Corcoran Gallery of Art through October 12.