life.(2) . However, polygraphs were not practical for most office purposes and were never widely used in businesses. Hawkins & Peale lost money producing polygraphs. The problem was their "inherent instability, and constant need for repair and adjustment."

Letter copying presses

In 1780 James Watt obtained a patent for letter copying presses, which James Watt & Co. produced beginning in that year. Letter copying presses were used by the early 1780s by the

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