The other special effect technique that G.A. Smith initiated was reverse motion and the quality of self-motivating images. He did this by repeating the action a second time, while filming it with an inverted camera, and then joining the tail of the second negative to that of the first. The first films made using this device were Tipsy, Topsy, Turvy andThe Awkward Sign Painter. The Awkward Sign Painter showed a sign painter lettering a sign, and in the reverse printing of the same footage appended to the standard print, the painting on the sign vanished under the painter's brush. The earliest surviving example of this technique is Smith's The House That Jack Built, made before September 1901. Here, a small boy is shown knocking down a castle just constructed by a little girl out of children's building blocks. Then a title appears, saying “Reversed”, and the action is repeated in reverse, so that the castle re-erects itself under his blows.
Cecil Hepworth took this technique further, by printing the negative of the forwards motion backwards frame by frame, so producing a print in which the original action was exactly reversed. To do this he built a special printer in which the negative running through a projector was projected into the gate of a camera through a special lens giving a same-size image. This arrangement came to be called a “projection printer”, and eventually an “optical printer”. With it Hepworth made The Bathers in 1900, in which bathers who have undressed and jumped into the water appear to spring backwards out of it, and have their clothes magically fly back onto their bodies.
The use of different camera speeds also appeared around 1900. To make Robert Paul's On a Runaway Motor Car through Piccadilly Circus (1899), the camera was turned very slowly, so that when the film was projected at the usual 16 frames per second, the scenery appeared to be passing at great speed. Cecil Hepworth used the opposite effect in The Indian Chief and the Seidlitz Powder (1901), in which a naïve Red Indian eats a lot of the fizzy stomach medicine, causing his stomach to expand vastly. He leaps around in a way that is made balloon-like by cranking the camera much faster than 16 frames per second. This gives what we would call a “slow motion” effect.
