Created in 1925, Marcel Duchamp’s Rotary Demisphere (Precision Optics) is a kinetic sculpture that turns itself on at random intervals. Back in Paris after World War I, Duchamp experimented with machines that produced optical effects — work he had begun in New York. When this machine is set in motion, the circles appear to pulsate toward the viewer. The copper ring around the dome’s circumference is engraved with French words chosen for the way their sounds echo one another: Rrose Selavy et moi esquivons les ecchymoses des esquimaux aux mots exquis (Rrose Selavy and I dodge the Eskimos’s bruises with exquisite words).
Rotary Demisphere is part of the Permanent Collection at the Museum of Modern Art in NYC. Find it in the Painting and Sculpture Galleries.