First part of a file of photocopies of correspondence between Ernest Lenaerts and his managers at Lyons - John Simmons, W.J. Edwards and T.R. Thompson, during Lenaerts' secondment to the Cambridge University Mathematical Laboratory, working as part of the EDSAC team under Maurice Wilkes. 

Many of Lenaerts' original letters were written enclosing reports on the progress of the EDSAC team, but photocopies of the reports themselves were not included in this file of photocopies.  Presumably the original reports are included in the archive copy held at Manchester, ref. GB 133 EHL/2 EDSAC.

Comprises:

• 11-12. Ernest Lenaerts (photocopy of file copy letter, manuscript) to John Simmons, 8th August 1946; 
• 13-15. Ernest Lenaerts (photocopy of file copy letter, manuscript) to John Simmons, 22nd Jan 1947; 
• 16-18. Ernest Lenaerts (photocopy of file copy letter, manuscript)to John Simmons, 16th Apr 1947; 
• 19-20. Ernest Lenaerts (photocopy of file copy letter, manuscript) to John Simmons, 23rd Jul 1947;
• Draft papers/notes (typescript) by Lenaerts, annotated at the top 'IDEAS' and dated September 1947:
  • 21. Electronics and Messrs J. Lyons & Co Ltd
  • 22-23. Suggested Changes
  • 24. Possible Applications of Electronics in Cadby Hall
• 25. John Simmons to Ernest Lenaerts, 11th December 1947; 
• 26. W.J. Edwards to Ernest Lenaerts, 16th December 1947; 
• 27. W.J. Edwards to Ernest Lenaerts, 23rd December 1947.

Page numbers in red were added by Peter Bird.

Research comments: There seem to be some anomalies in the dates of the earlier letters in this sequence. The established chronology of events relating to the start of the Lyons project to build a computer and their decision to send Ernest Lenaerts to Cambridge to work with Maurice Wilkes on EDSAC suggests that Lenaerts went to Cambridge in December 1947. This concurs with the last 3 letters in this sequence (from Lenaerts to John Simmons) but it therefore cannot be correct that Lenaerts was writing to Simmons in August 1946 and throughout the early part of 1947. The dates on the documents looks mostly clear but can only be an error. 

One of the letters, seemingly dated 23 July 1947, includes a note at the end referring to Dr [Julian] Bigelow's work on a wire recorder (an early form of magnetic storage). The American Julian Bigelow worked with John von Neumann at the Institute of Advanced Study in Princeton and is known to have visited Cambridge in July 1948 to see EDSAC. Lenaerts couldn't possibly have asked Bigelow in 1947 to supply details of his wire recorder on his return to the US, when Bigelow didn't visit until a whole year later. In fact, a letter from Lenaerts to John Simmons about Dr Bigelow's visit to Cambridge is held in this archive and is dated July 1948. It refers to the wire recorder but suggests that the American EDVAC machine, which Lenaerts suggests is likely to be completed before the end of 1948, won't make use of it.

Nonetheless these letters offer a unique insight into the post war years when the developments made in electronics during the war were starting to be applied to peacetime operations like food production at Cadby Hall. Lenaerts seems very aware of both the pace and the sheer scale of the changes that were afoot; he refers to it as 'this new industrial revolution' in the typescript letter dated September 1947. The document suggests that Lyons could pursue 'pulse electronics' in order to construct an 'electronic computor'. (LM)

Provenance :
The photocopies were originally requested by Peter Bird, as part of his research for LEO - The First Business Computer, and later donated to the NAHC, then transferred to CCH at the request of the LEO Computers Society for inclusion in their archive.