The collaboration of Stanford and Muybridge made it all possible: the wealthy Stanford provided the funding and direct purpose needed by Muybridge, the creative, self-described "artist photographer."
The components required that day included twelve cameras, equipped with "fast" stereo lenses and an electrically-controlled mechanism to operate the cameras' special shutters. Wires laid underground along the track at 21-inch intervals released the shutter of each camera as the wheels of the sulky made contact.
twelve pictures -- taken in about half a second -- were the result
of Eadweard Muybridge's long work designing and assembling the equipment
used (in conjunction with a group of scientists & engineers) and formulating
the vital chemical recipe to develop clear photographs of fast movement.