(The following example of Marcel Duchamp's encounter with the mind of Leonardo da Vinci is exerpted from a longer essay. Duchamp discovered Leonardo's anatomical writings and drawings, through photogravure reproductions, in the Bibliothèque Sainte Géneviève in Paris, first as a curious visitor in 1910, then as a professional librarian with a great deal of spare time, in 1913-14.)

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Note by Leonardo da Vinci, from: Charles O'Malley and J. B. Saunders (eds.), Leonardo on the Human Body, Dover: New York, 1982, p.296.