Mary Coombs is recognised as being the first female commercial programmer, she was the first woman to work on the LEO computers. Her father, William Blood, believed in women's education and her sister worked in microbiology and bacteriology. Unlike her sister, and unlike others in computing, she did not have a background in maths or science. The National Museum of Computing documents her contribution. She graduated with a degree in French from Queen Mary University in London. She later moved to Surrey, when her father became a Medical Officer for the catering company, J. Lyons and Co. He was clear that women should have their own careers and interests.
After obtaining her degree, Coombs began worked at J. Lyons and Co. in 1951 as a temporary clerical worker—a job she reluctantly accepted while searching for a better alternative. Coombs' mathematical skills soon allowed her to transfer from the Ice Cream Sales department to the Statistical Office, where she heard that the division working on the LEO computers had been looking to hire additional programmers. The selection process, devised by Raymond Thompson, was conducted as a "computer appreciation course", which consisted of a grueling week of daytime lectures and evening written assignments designed to test the candidates' aptitude for computer work. Of the 10 who took part in the original selection process, she was the only female. Coombs' performance in the computer appreciation course was stellar, and as a result, she was one of just two candidates to be offered a job in the computer division, along with Frank Land. According to Coombs, she was one of a handful of women to take the computer appreciation course, and she was the only one to be offered a job as a result. Once Coombs began officially working with LEO in 1952, she was taught how to program by John Grover, one of the first LEO programmers. Initially, she was the only woman on the team and worked alongside Leo Fantl, John Grover, and Derrick Hemy, using LEO to automatically calculate payroll for employees at J. Lyons and Co. The team later went on to do payroll for Ford Motor Company using LEO. Coombs is recognised as the first woman to work on a commercial computer. Coombs continued to work for J. Lyons and Co as the LEO II and LEO III were built. She spent most of her time as a supervisor, checking for logical and syntactical errors in the programs that other people wrote. She developed programs for internal company use and for outside clients as another portion of the business computing service offered by the firm. She was also in charge of rewriting programs from LEO II to work with LEO III, since LEO III used a different programming language. J. Lyons and Co. provided a good work environment for Coombs. The company had a number of sports clubs that Coombs was involved in and even an Amateur Dramatic Society. However, the company provided very low pay.
After J. Lyons and Co.
Coombs was transferred to English Electric Leo Computers in 1963, a company jointly created by the merger of J. Lyons and Co. and English Electric. Later, in 1968 she was transferred to International Computers Limited when they bought out English Electric Leo Computers. In 1964, because of family commitments she moved from working full-time to part-time. She continued to work in the computing business mainly editing manuals. She briefly taught a computer programming course at Princess Marina Centre at Seer Green for disabled residents. In 1969, when she realised that she would not be able to go back working full-time, Coombs left the LEO team and briefly worked for Freelance Programmers, a company started by Dame Stephanie Shirley. After three years at home looking after her children she returned to work, firstly as a Primary School teacher in a private school and then following a year working for a Post-graduate Certificate in Education, about 10 years in Primary Schools in Bucks". After quitting from her teaching position, she has been teaching piano, and running the church choir as well as keeping up with other hobbies.
LEO Computers
Coombs was the first woman to ever work as a programmer in the LEO computers business. She and her husband were co-workers there. They eventually had a daughter together, who unfortunately became disabled as a toddler, which made Mary think either she should quit her job or work part-time. Her daughter died at the age of 6. However, Mary and John adopted three children.
