physionotrace

thumb|Pierre Gaveaux, 1821, by [[Edme Quenedey (1756–1830) after a physiognotrace]]

A physiognotrace is an instrument, designed to trace a person's physiognomy to make semi-automated portrait aquatints. Invented in France in 1783–1784, it was popular for some decades. The sitter climbed into a wooden frame (1.75m high x 0.65m wide), sat and turned to the side to pose. A pantograph connected to a pencil produced within a few minutes a "grand trait", a contour line on a piece of paper. With the help of a second scaling-down pantograph, the basic features of the portrait were transferred from the sheet in the form of dotted lines to a copper plate, which had previously been prepared with a ground for etching. One week later, the sitter received an etched plate and twelve little prints. The device but also the aquatint prints are called physiognotraces.