Watercolor on paper; 8½ x 7¾ inches). Jefferson Papers, Library of Congress, Washington, DC.
This physiognotrace — a mechanical drawing device — was patented by John Hawkins in 1802. Peale drew it and explained it in a letter to Thomas Jefferson (28-Jan-1803):
A is a board that moves up and down in the frame B, B. which is fastened to the wall with brackets C, C. — This movement is convenient to suit the height of different persons, and it is secured to the place by means of a screw on the back part, — D is a hollowed board projecting 2½ Inches, to allow the Pantagraph to move behind it. The person to be traced, setting in a chair rests their head on the concave part, & the hollow of the board below imbraces the shoulder — The Physiognotrace is fixed to the board A at a, and in the center of the point b, is a conic steel point with a spring to press it against the paper represented by the doted [sic] line. The steel point is taken off the paper by means of a lever; having the upper end turned at a right angle and the spring in a wedge form, and the other end extended to the point on the right to begin [reach?]
C is an Index made of brass, the point of which has [plate?] on each side connected by a center pin. — to the outer plate is screwed a piece of brass 5 Inches long, with a thin edge, which edge is exactly perpendicular to the center of the joint.
This Index moving round to trace any subject that the edge is kept too, as it moves, the steel point in the center of the upper joint gives a diminished size a perfectly correct representation. The paper to be traced is fixed on a square board by means of an iron rim, and it is in turn placed on a door hinged to the back part of Machine, & [shut?] into a [rabbet?] made to receive & keep it at a proper distance from the steel point.