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What has been digitised?

The Modern Records Centre holds the archives of the statistician John Simmons (1902-1985), including key material on the development of the pioneering LEO computers by J. Lyons & Company Ltd. during the 1940s and 1950s.

A selection of documents about the development of 'LEO I', the world's first business computer, have now been digitised and made available online:

  Electric machines: Report of a visit by Mr Booth and others to Cambridge November 1947
  Report on payroll preparation by electronic computer 16 January 1948
  Site for electronic computer (memorandum)
29 November 1948
  Electronic computer (report no.1) 4 February 1949
  Development of the electronic calculating machine (report no.2)
8 April 1949
  Lyons electronic computer (report no.3) 23 May 1949
  The development of EDSAC (report) 23 May 1949
  Lyons Electronic Office (report no.4) 14 June 1949
  Lyons Electronic Office (report no.5) 31 August 1949
  The layman's guide to LEO (computer manual) [1950?]
  LEO (report no.6) 31 January 1950
  Circulars relating to demonstration of LEO 2 March 1950
  Reactions to the demonstration of LEO on 7th and 8th March 1950 20 March 1950
  Notes on LEO and office management 29-30 March 1950
  Notes on LEO and office management February-June 1950
  Visit of Lord Halsbury (memorandum) 1 May 1950
  LEO (report no.7) 3 July 1950
  LEO (report no.8) 11 December 1950
  LEO (memorandum) 2 April 1951
  Demonstration of LEO (notes for talk) 17 April 1951
  Menu for dinner to celebrate the successful demonstration of clerical work performed by the calculator of LEO 16 May 1951
  LEO (report no.9) 18 June 1951
  LEO (report) 22 February 1952
  Development of LEO to link with a line-a-time printer (memorandum) 17 June 1952
  Modifications to LEO to make it independent of Standard's equipment (report) 3 October 1952
  LEO (report no.10) 27 November 1952
  Future policy for LEO (memorandum) 19 June 1953
  Memorandum regarding near-completion of LEO 7 December 1953
  LEO: Lyons Electronic Office (promotional leaflet) 16 February 1954
  Menu for dinner to celebrate the inauguration of LEO 27 May 1954
  LEO (report no.11) 30 June 1954
  LEO chronicle 1947-1954 [1954?]
  Visit of T.R. Thompson and A.B. Barnes to the USA: General report to directors 14 December 1955
  Photographs of LEO  


We have been unable to identify the current copyright holders for the defunct companies LEO Computers Ltd. or J. Lyons & Co. Ltd. Please contact us if you think that your company has inherited their copyright.