"Do all four of a horse's hooves leave the ground at any point during a gallop?" It was this simple question that sparked the invention of film in 1872. Since Leland Stanford and his colleagues had opposing views, they made a bet and hired a photographer to document the horses's hooves. Cameras at that time were unable to capture things moving quickly, so the photographer devised a plan that would lead to his recognition as one of the founding fathers of the motion picture. Watch the following video to hear the full story.