Etienne-Jules Marey joined his interests in medicine and mechanics to invent instruments useful in the realms of physiology and cinematography. To Marey the movie camera was an instrument to be used in research on animal locomotion, but to the rest of the world, it was the force behind the advent of the motion picture industry.

Born in Beaune, in the Burgundy region of France, on March 5, 1830, Marey was the son of a wine merchant and a schoolteacher. To please his father, Marey studied medicine at the Faculty of Medicine in Paris. He chose physiology because it was the only science field in which he could combine his interest in animals and mechanics.

Marey was particularly intrigued by blood circulation. In his first decade of research, Marey invented the sphygmograph, a device that graphically records the pulse, and the kymograph, which graphically depicts blood pressure. After 1868, when he became...