PHYSIONOTRACE - "Portrait of a woman, right profile". 1810. Portrait engraved with a physionotrace by Chrétien (1754-1811). Wove paper. Margins. The physionotrace was a machine invented in 1784 or 1785 by Gilles-Louis Chrétien that enabled life-size pastel portraits to be drawn "mechanically". These portraits, called "grand trait", were then etched on a copper plate. 15 x 11.5 cm. Condition B/C (rare small stains or foxing in the margins, lightly oiled).