Marcel Duchamp (American, b. France, 1887-1968). Detail, To Be Looked at (from the Other Side of the Glass) with One Eye, Close to, for Almost an Hour, 1918. Oil, silver leaf, lead wire, and magnifying lens on glass, mounted in a standing metal frame, 20 1/8 x 16 x 1 3/8 inches. Museum of Modern Art, Katherine S. Dreier Bequest. Photo: Jacquelynn Baas.