The Polygraph, the Copy Press, the Letter Press

The copy press was widely used by clerks and in law offices in the late eighteenth through all throughout the nineteenth century. The method worked like this: You would take a document or page that you wanted a copy of, and then you would take a very thin piece of paper. It's something that early users of the polygraph actually complained about, saying, oh, ye, the copy made by the polygraph is so much more legible than copies made with the letter copying press.