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Mary Coombs

In June 2022, the LEO Computers Society published an obituary to Mary Coombs (formerly Mary Blood) in their newsletter LEO Matters:

It is with great regret that we report that Mary Coombs, (née Blood), one of the LEO pioneers passed away on 28th February 2022 at Stoke Mandeville Hospital, at the age of 93.

We print below the obituary written by John Aeberhard and then a personal tribute to Mary from her friend and fellow-programmer, Frank Land.  On the LCS website you will find links to the very many printed and online national and international obituaries published after Mary’s death. There is also a link to the BBC4 programme ‘Last Words’ which featured Mary with contributions from Georgina Ferry and Frank Land.

Mary Coombs

Mary Coombs, the first woman to write programs for Lyons Electronic Office (LEO), the world’s first business computer, has died at the age of 93 in Stoke Mandeville Hospital following complications arising after a Covid infection. 

Mary Blood as she then was joined J Lyons & Co in 1952 as a management trainee, just a few months or so after LEO had run its first business application and following a holiday job arranged for her by her father, the company’s senior medical doctor. Initially, she was put to work in the company’s statistical office operating a calculating machine, but following a stellar performance in an aptitude test, was offered the chance to join the LEO team which, she always said, she jumped at.

Well aware of her role as a computing pioneer – “We were all engaged in a big adventure,” she would say – she joined the computing team when there were just three programmers on board, all men, becoming the only woman in a class of twelve on an introductory computer appreciation course. From here, it was straight into payroll applications for a rapidly growing range of external clients as well as developing programs for internal company use.

It was a huge challenge.  Not only had much of the work never been done before, but as Mary would point out, she was working on a notoriously unreliable valve computer, but also one that had just 2K bytes of computer storage compared to the “umpteen gigabytes” available to present programmers.

“When it was LEO 1 you had to know a lot about the machine itself because there was so little storage space that every instruction had to be essential, or it had to be knocked out,” she would tell interested friends. 

As well as working on programming to handle payroll for companies such as Ford Motor and Lyons itself, Mary was also involved in such jobs as tax tables for the Inland Revenue, Met Office work and the calculation of ballistics for the Army. She went on to become a supervisor and worked to locate and repair coding errors in the programs created by others.

Family commitments meant that she ceased full-time programming in 1964, but continued to work part-time editing computer manuals and for a few months ran a computer programming course for severely disabled residents at the Princess Marina Centre, Seer Green, sponsored jointly by ICL and Buckinghamshire County Council.

It was not until late 1969 that she ended her formal connection with the LEO team.

Mary returned to full-time employment in September 1973 as a primary school teacher, completing a three-year postgraduate teaching course in 1976.  She retired from teaching in 1985 and went on to work as a buyer in the water treatment industry.

Mary Clare Coombs, nee Blood, was born on 4 February 1929 to her doctor father, William, and his wife, Ruth. She was educated at Putney High School and St Paul’s Girls School.  Her favourite subject at school was maths, giving a clue to her later occupation.  She went on, however, to read French and gain a BA Hons degree at Queen Mary College, London University.

Mary married John Coombs (d.2012), himself briefly a computer programmer on the LEO team, in 1955.  Together they had a daughter, Anne, who sadly died aged just six.  Between 1965 and 1969 they adopted three more children, Andrew, Paul and Gillian.  They survive her as do a younger sister, Ruth and three grandchildren, Grace, Jemma and John.

A tribute to Mary Coombs by Frank Land

Transcribed by Hilary Caminer from the recording of the LEO Computers Society zoom on 25/3/2022. This zoom session was held in Mary’s honour.

‘I want to say a few words about Mary who died so recently and tragically. I knew Mary as a personal friend and much of my recollection is of her as a personal friend. I remember we met first at the Appreciation Course which Lyons gave to their own people to see how many of them might fit into the LEO team. At the time Lyons thought they could recruit most of the people they needed for their LEO team from inside and some of the first generation like the Hemy’s and so on had all come from Lyons.

On that course I first met Mary. I didn’t recognise her as anything special but she did exceptionally well on the course on her own. She had studied French, but she was a good mathematician and she liked mathematics and indeed one of her obituaries called her a mathematician though she never studied mathematics. We were both on the same course.

I survived the course because I had a wife who was a mathematician and helped me – I don’t know where I would be now if she hadn’t helped me! Mary managed it on her own and we two were chosen to join the LEO team.

She made an immediate impression, she was thorough, she was good – and we became friends. What I remember most about her was that she was kind. I remember she was always out to help the disadvantaged.

I remember our eldest daughter was the same age as her daughter, the daughter who later died – and I remember sitting on the lawn at High Wycombe with the two girls playing together. Then, on another occasion, they were playing and their daughter hadn’t progressed and ours had and we knew then that something was wrong.

Anyway, Mary was clearly a very thorough and good programmer. She always thought that she was kept at the supervisor level rather that at management level because she was too good at her job. But I think it was more because of the glass ceiling which affected most women.

What is perhaps ironic is that Mary, through her death achieved more for the LEO story than she ever did in her life, notable as it was that she was the first woman to write a commercial program. But that wasn’t her strength – her strength was her reliability, that she was good at her job, that she was able to deal with other people. The irony is now is that through her death, through the very many obituaries she has received she has raised the status of LEO and made the LEO story better known throughout the world in a way that would have been difficult without that happening. Ironic, but true.

I remember Mary as a kind person, even when she had problems with her own child, a little bit later on she would look after somebody with MS because she felt for them and throughout her life she had this particular kindness. Some people may have called her ‘scary Mary’ or ‘bloody Mary’ but these were just nicknames people used. I think we each had our moniker – I don’t know what I was called, but I am sure it wasn’t flattering.

So let me close by paying tribute to a person who was really a wonderful person for her ability, for her continued striving for what is right and good. She is a great loss to the Society and she is a great loss to humanity.

Let me close on that note as a tribute to Mary Coombs, née Blood as was. Thank you.’ 

Photo courtesy of Mike Hally

Date : June 2022

This exhibit has a reference ID of CH70367. Please quote this reference ID in any communication with the Centre for Computing History.

Mary Coombs

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