 At that time, many versions of these instruments were being used all over the East Coast in the United States, some of which predated Hawkins's, and which were capable of quickly making machine-made profiles.By 1802, in response to the popularity of silhouettes, which were invented in the late eighteenth century, Peale introduced the British inventor John Hawkins’s (1772–1855) physiognotrace at his museum in Philadelphia.While the operator traced the sitter’s head, the mechanism impressed the image onto a piece of paper that was often folded to produce multiple portraits.