TODAY is the 56th anniversary of the last day of the pre-xerographic era.

For it was on 22 October 1938 that Chester Carlson made the world's first Xerox copy. The image said: '10-22-38 Astoria', which may help to explain why some 20 companies expressed a positive lack of interest in the invention.

Carlson, who had lost his job with Bell telephones in 1930, finally achieved funding for the project in 1944, but it was another 15 years before the first Xerox 914 photocopier came on to the market. Americans alone now make 400 billion photocopies a year: 750,000 every minute of every day.

Information on the origins of the photocopier from: The ITN Book of Firsts - The Invention and Origin of Nearly Everything, by Melvin Harris, published by Michael O'Mara Books, pounds 14.99.