Falling Cat is an 1894 short film produced and directed by Étienne-Jules Marey, a French scientist. It was filmed in a public park, Bois de Boulogne, and released in France. It is believed to be the first motion picture in history to show a live cat. The film consists solely of the feline falling down and landing on its feet. Marey had assembled a camera that was capable of taking twelve consecutive frames a second. It resembled a short barrelled shotgun with a magazine. With this, he studied various animals in action. His most famous study was his ‘animated zoo’, in which this cat was dropped from a height of a few feet in order to see if it always landed on its feet.

M. Marey thinks that it is the inertia of its own mass that the cat uses to right itself. The torsion couple which produces the action of the muscles of the vertebra acts at first on the forelegs, which have a very small motion of inertia on account of the front feet being foreshortened and pressed against the neck. The hind legs, however, being stretched out and almost perpendicular to the axis of the body, possesses a moment of inertia which opposes motion in the opposite direction to that which the torsion couple tends to produce. In the second phase of the action, the attitude of the feet is reversed, and it is the inertia of the forepart that furnishes a fulcrum for the rotation of the rear.

Falling Cat 1894

Despite the publication of the images, many physicists at the time maintained that the cat was still "cheating" by using the handler's hand from its starting position to right itself as the cat's motion would otherwise seem to imply a rigid body acquiring angular momentum.

"There is a tradition in Trinity that when I was here I discovered a method of throwing a cat so as not to light on its feet, and that I used to throw cats out of windows. I had to explain that the proper object of research was to find how quick the cat would turn round, and that the proper method was to let the cat drop on a table or bed from about two inches, and that even then the cat lights on her feet."[1] Maxwell's and other scientists interest with so-called "cat turning" was reputed to have caused the death of many cats after being dropped from windows of multi-storied buildings.[citation needed] Maxwell in particular was interested in discovering the precise height that a cat needed to be dropped from so that the cat would be incapable of using its righting reflex to land on its feet, an endeavor in which he eventually succeeded.

Whereas the cat-falling problem was regarded as a mere curiosity by Maxwell, Stokes, and others, a more rigorous study of the problem was conducted by Étienne-Jules Marey who applied chronophotography to capture the cat's descent on film using a chronophotographic gun. The gun, capable of capturing 12 frames per second, produced images from which Marey deduced that as the cat had no rotational motion at the start of its descent the cat was not "cheating" by using the cat handler's hand as a fulcrum. This in itself posed a problem as it implied that it was possible for a body in free fall to acquire angular momentum. Marey also showed that air resistance played no role in facilitating the righting of the cat's body.

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