Portable copying apparatus, c 1800.
© Science Museum / Science & Society Picture Library
This is one of the letter copying desks designed by James Watt Junior (1769-1848), the son of Scottish engineer James Watt (1736-1819), and manufactured by James Watt & Co of Soho, Birmingham. The copying proces used by this apparatus was patented by James Watt in 1780. A letter written in special ink is placed against dampened paper and pased through the roller pres. Some of the ink is transferred by the presure to the copy paper and the letter can be read from the reverse side of the page.