A film made without a camera in which both image and sound are the result of the same chemical process. Raw film was spooled onto a spiral and partially submerged in developer, so that only half the film is developed, leaving the trace of a time spiral in the image and (optical) sound. The film can be projected in either direction. Outwards, from the centre of the spiral, we hear a decelerating sound like someone regaining their breath. G.S.