LEO editor

Zoom Recording of a tour of the Centre for Computing History now available

Jason Fitzpatrick the CEO of the CCH gave LEO Computer Society members a virtual tour of the exhibits at the Museum on 27th April. The meeting was held on Zoom and recorded for those who wanted to attend but who were not able.

The recording is now available on this Website and can be viewed by following the link above. In addition an updated version of LEOPEDIA as at 30th April has been also uploaded to the Website

The Zoom Video can be viewed by following This Link and the updated LEOPEDIA Here

Mary Coombs (Updated 26 March with additional links)

It is with great regret that we have to report that Mary Coombs, one of the LEO pioneers passed away  on 28thFebruary 2022 at Stoke Mandeville Hospital, at the age of 93. Mary was the World’s first female business computer programmer joining the LEO team in 1952. We will let members know when the funeral is arranged. Mary was a good friend of the society and will be sadly missed. You can see Mary’s obituary on the CCH Website Here. Other published Obituaries include The Times, Computer Weekly, Computing, BCS, The Register, The News Trace, The Guardian , The Daily Telegraph, The ACM, Wikipedia, Bucks Free Press, Elective College and Radio 4’s  Last Word on Friday (18th March) at 4p.m. , repeated on Sunday (20th March) at 8.30 p.m. – and available as a podcast thereafter -Listen at: https://www.bbc.co.uk/programmes/b006qpmv

There is also a recording of a recent Zoom meeting held to remember Mary –Zoom Recording and copy of the presentation deck used by Hilary Caminer Presentation

Mary appeared in our/CCH recent film about LEO remembering the early days of LEO (and if you haven’t seen it or want to watch it again go here )and there was a short BBC Witness History feature made about her- available for viewing at https://www.bbc.co.uk/programmes/p07w35t and her school, Putney High School also celebrated her at:    https://www.youtube.com/watch?v=oHiCMfHydlo

For those interested in Mary’s life you can read a transcript of her Oral History at the British Library here.

Picture of Mary below. Copyright Mike Hally/LEO Computers Society

LEO: New film celebrates the 70th anniversary of the world’s first business computer

Lyons Electronic Office: The Story of the World’s First Business Computer

To mark the 70th anniversary of LEO, the world’s first business computer, the LEO Computers Society and the Centre for Computing History (CCH) are launching a new specially commissioned short film. Funded by the National Lottery Heritage Fund as part of efforts to preserve and promote the history of this remarkable British invention, the film will be released on the 30th November – the day in 1951 that LEO ran its first program. The film will introduce a whole new generation, from secondary school age upwards, to the remarkable story of the birth of computing technology that, today, we take for granted.

The film will premiere on YouTube at 7pm on 30th November 2021 at https://youtu.be/Rzu68nRVwtE.

LEO 70th Birthday

We’re sharing some business computing history over the next week as we lead up to the 70th anniversary of LEO completing its first program. Come & learn more at our LEO Weekend on 4th – 5th Dec, and see our special exhibition & film screening:

Link to Page at CCH

Lyons visit to the USA 1947

This ‘American Tour’ report kickstarted the world of business computing. Lyons visited the USA in 1947 to learn about computers, from ENIAC to IBM. They weren’t impressed – but found out about EDSAC here in Blighty, then built their own machine

This ‘American Tour’ report kickstarted the world of business computing. Lyons visited the USA in 1947 to learn about computers, from ENIAC to IBM. They weren’t impressed – but found out about EDSAC here in Blighty, then built their own machine!



Originally tweeted by Computing History (@computermuseum) on 24 November 2021.

LEO Matters Issue Nov 2021 Volume 10 – 70th Anniversary Issue

LEO Matters from Novemeber 2021 in desktop published format. Edited by Hilary Caminer and published by Bernard Behr.

Contents: (Clicking on the highlights below will take you straight to the page containing the item highlighted. – Note on slow Internet connections this may not work and you will be taken to page 1 in all cases).To open the whole document click on the image of the front page.

Message from Our Chairman by Peter Byford Page 1

Report on AGM Page 2

The LEO Archive at CCH by Lisa McGerty Page 3

1951 a year to remember by Hilary Caminer Page 4

My Life with LEO by Helen Jackson nee Clark Page 6

“Johnny Come Lately” by John Daines Page 7

A Customers Point of View by Anthony Thorpe Page 8

BBC’s Tomorrow’s World by Jim Johnson Page 9

Aus Mein Lieben by Alan Hooker Page 10

The Sporting and Social Side Part 2 by Peter Byford Page 11

Voice Guidance Page by Alan Williams 12

Gift and Souvenir Page 13

Dates for Your Diary Page 14

Dates for your diary. Events for 2022. Follow this link for further information

There was another Zoom on Monday 24 January 2022 at 15:30 GMT.
The topic was “Inside the LEO archive” and was led by Luke Thorne, our Archivist at the Centre for Computing History at Cambridge. A recording is available at https://leo-computers.org.uk/Videos/Clipped_LEO_Archive.mp4


REUNION and LEO Exhibition: Sunday, 10th April 2022

From midday at the Victory Services Club, Marble Arch, London W2 2HF. As usual this will be an opportunity to meet old friends and colleagues and others with an interest in early computing. There will be refreshments and exhibitions of LEO related materials – as well as the usual raffle! Details to follow in the new year.

Tickets (to include a light lunch) cost £27 if bought before 31st January 2022 (£30 thereafter.)

To download a form to send with your application and with payment details click here

If you have any queries about this event or wish to book tickets, please email reunion@leo-computers.org.uk


September 1951  – At J. Lyons & Co on Wednesday, 5th September 1951 the Bakery Valuations programme was run to completion on real data as an experiment to test the hardware.  As noted in Ernest Lenaerts notebook for that date it ran from 3:50 to 5:35 without a fault and was the longest run of any programme at that time.

Zoom For LEO Computers Society Members

We are organizing a new series of Zoom Meetings.

See Below

Wednesday Online celebrations!

During the past year we have discovered that online forums and presentations have been a great way to get our members together. Zoom has allowed former colleagues, now living in different continents to reminisce together and for, 22nd September 17.00 BST AGM including updates on all our activities and a vote for Trustees. This will be followed by a discussion among members on ideas for the future. 

Tuesday, 19th October 10.30 BST   We hope to bring you a tour of The National Museum of Computing at Bletchley Park. As many of you will know, TNMoC has a reconstruction of EDSAC, the computer built at Cambridge which Lyons helped to fund so that they could develop a commercial computer for themselves.

Wednesday, 17th November 15.00 GMT  Our new LEO Film! By this date in 1951, LEO was almost ready to run its first regular clerical run working on the Lyons Bakery Valuations Job.  As part of our National Lottery Heritage Fund programme, we have had a 15 minute film made about LEO. This will be given its press launch in late November to chime with the actual anniversary itself, but we have managed to arrange for our members to be given an exclusive pre-launch viewing. The film will be followed by an opportunity for members to comment and for a discussion with the filmmakers.


Antiques Road Trip

The BBC programme Antiques Road Trip made a stop off at Cambridge to visit the Cambridge Computer History Museum and interviewed Jason Fitzpatrick the Museum founder. Jason covered many interesting topics including early calculators, EDSAC, LEO and the BBC Micro and ARM chips.

You can hear and view the section from Cambridge Here