Etienne-Jules Marey was a French scientist, physiologist, and chronophotographer. Chronophotography is a scientific measurement technique in which photography is used for analysis, often the locomotion of living creatures. In fact, Marey coined the phrase.
Marey devised integral cameras using a single lens and a single imaging surface for photography of phases of the moon. This contrasted with the efforts of others in the field, who used multiple cameras or multiple-lens cameras.
In the 1880s Marey devised a camera that looked like a trolley car that could follow a moving subject. It was during this time, in 1885, that he produced this schematic visualization of movies he made of running people to understand the physiology of human movement.
