Pioneering woman programmer on the first business computer
MARY COOMBS, who has died aged 93, was the first woman to write programs for Lyons Electronic Office (LEO), the world’s first business computer.
LEO was created by J Lyons and Co, operator of tea shops, manufacturer of biscuits, founder of the Wimpy burger chain and a company with a longstanding culture of technological innovation. The computer, which crunched its first numbers on November 17 1951, occupied 5,000 square feet at the firm’s headquarters at Cadby Hall, Hammersmith.
Its first task was to calculate the costs of the weekly bakery distribution run, a task that had previously been carried out by hand by accounts clerks. Within two years the machine was reliable enough to be trusted with the more important task of calculating the payroll.
Mary Blood, as she then was, joined J Lyons & Co in 1952 as a management trainee on £300 a year, 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 she was offered the chance to join the LEO team.
“We were all engaged in a big adventure,” she recalled. She joined the computing team when there were just three programmers on board, all men, becoming the only woman in a class of 12 on an introductory computer course. From there, 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 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 recalled.
As well as working on programming to handle payrolls for companies such as Ford Motors and Lyons itself, Mary became 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 she 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, later reflecting that Lyons had been an excellent company to work for: “The pay wasn’t good, but you were terribly well treated.”
Mary Clare Blood was born on February 4 1929 to William and his wife, Ruth. She was educated at Putney High School and St Paul’s Girls’ School, where her favourite subject was maths. She went on, however, to read French at Queen Mary College, London University.
She returned to full-time employment in 1973 as a primary school teacher, completing a postgraduate teaching course in 1976. She retired from teaching in 1985 and went on to work as a buyer in the water treatment industry.
In 1955 she married John Coombs, himself briefly a computer programmer on the LEO team. They had a daughter, who died aged six, and they adopted two sons and a daughter, who survive her, her husband having died in 2012.