Minor, intentional differences between 3,230 supposedly perfect copies of commentaries on this work were uncovered by Stephen Jay Gould and his wife. For a 1964 retrospective, Richard Hamilton made a replica of three silver “oculist witnesses” in this work. After not working on it for six months, the artist of this work used the thick layer of dust which had accumulated on it as pigment. Preparatory notes for this work were collected in The (*) Green Box. (10[1])This work’s artist declared it “finished” when it was accidentally damaged en route to Katherine Dreier’s house. After the completion of this work, its artist supposedly retired from art to play chess. A water wheel (-5[1])powers a “chocolate grinder” in this work, in which nine “Malic Molds” attempt to win the love (10[1])of a bug-like figure. For 10 points, male and female figures title what work consisting of two glass panels by Marcel Duchamp? ■END■ (10[1])