The science of photography gave birth to modern motion pictures. This was not, however, a rapid process. The motion pictures we know today are the result of a long evolution of arts and sciences. Motion pictures are the product of a relatively complex illusion. The human brain perceives motion when pictures, taken in rapid sequence, are flashed at 15 or more frames per second--so we are able to amuse ourselves with the illusion of live action on the screen.

Sequential photographs were produced as early as 1860, but the true motion picture remained in the distant future. In 1877, Eadweard Muybridge, a student of animal motion, was attempting to prove that all four of a horse's hooves leave the ground when the animal gallops. A system of 24 cameras took sequential photographs of a galloping horse, and Muybridge indeed proved his theory. He also popularized this amazing illusion of motion...