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After moving back to Paris in 1923, at Andr Breton’s urging and through the financing of Jacques Doucet, Duchamp built another optical device based on the first one – Rotative Demisphre, optique de prcision (Rotary Demisphere, Precision Optics). This time the optical element was a globe cut in half, with black concentric circles painted on it. When it spins, the circles appear to move backwards and forwards in space. Duchamp asked that Doucet not exhibit the apparatus as art.
Rotoreliefs were the next phase of Duchamp’s spinning works. To make the optical “play toys” he painted designs on flat cardboard circles and spun them on a phonographic turntable. When spinning, the flat disks appeared three-dimensional. He had a printer produce 500 sets of six of the designs, and set up a booth at a 1935 Paris inventors’ show to sell them. The venture was a