Obituary: John Pinkerton

LAST month a 400-page book, LEO: the incredible story of the world's first business computer, was published in New York. The book celebrates Leo, a computer built by the British catering company of J. Lyons, and the most romantic of all the pioneer computing machines. John Pinkerton was chief engineer of Leo, and his career tracked the rise and turbulent progress of the British computer industry.

Pinkerton was educated at King Edward VI School, Bath, and Clifton College, Bristol. In 1937 he entered Trinity College, Cambridge, where he read Natural Sciences, graduating in 1940. His war years were spent on radar research. At the end of the war he returned to Cambridge, as a research student in the Cavendish Laboratory.

In the immediate post-war years computers were in the air, especially at Cambridge University, where the director of the mathematical laboratory, Maurice Wilkes, was at the very forefront of development, building a computer known as the Edsac. Pinkerton - who knew Wilkes from wartime radar research - took not much more than a passing interest in computers until he learnt of Lyons' computer developments.

The catering firm of J. Lyons was a national institution, famed for its high-street teashops and bakery goods. In the business world it was also famed for its streamlined offices, which employed many hundreds of accounts clerks to deal with the sales of millions of cups of tea and countless cakes each day.

Lyons' interest in computers dated from 1947, when two of its senior office managers made an American tour to see what was new in the office world. They came back convinced that the way of the future would be computers, and set out to buy one. However, it would be five or more years before machines became commercially available, so they decided to build their own. Contact was established with Wilkes at Cambridge, who agreed to let Lyons make a copy of the Edsac computer. Lyons also needed a chief engineer to build the machine, and Wilkes pointed Pinkerton in their direction; he never looked back.

A natural engineer, Pinkerton's philosophy was not to change anything in the Edsac's design which he did not fully understand; he later remarked, "Since we didn't understand very well why it was designed, we didn't make very many changes at all." In fact, Pinkerton made several key innovations, the most important of which was reliability. The 6,000-valve Leo was to function at the heart of an operational business and had to be available day in, day out, with no significant breakdowns. The techniques Pinkerton developed, such as the "marginal testing" of components that were about to fail, was classic engineering work that became standard industry practice.

Leo became operational in early 1951, and gradually took over more and more of Lyons' office routine. By 1954, it was used to capacity, and it was decided to build a second machine. Word of Leo had spread wide in the business community and several other firms, such as the Ford Motor Company, had expressed interest in having a machine too. So, in 1955 Lyons decided to go into the computer business and created a subsidiary, Leo Computers Ltd. Pinkerton became technical director of the new firm, and oversaw the development of Leo's successors, Leo II and Leo III.

By the early 1960s, with the onset of American competition and the need to develop transistorised computers, the costs of staying in the computer business had begun to soar. Lyons made the sad but inevitable decision to quit while the going was good, and sold out to English Electric. Pinkerton was appointed head of research in English Electric Computers, but more reorganisation lay ahead.

In the mid-1960s, Harold Wilson's Labour government was determined to rescue British industry in general and the computer industry in particular. Bullied by the Ministry of Technology, English Electric Computers merged with the other major British player to form a "national champion" computer firm, ICL, in 1968. The next 20 years were times of great volatility for ICL, as its senior managers constantly did battle to keep the company competitive against IBM and the American giants. For the remainder of his career until he retired in 1984, Pinkerton's principal role was as a product strategist, advising on how ICL's computers should anticipate and evolve with the ever more rapid shifts in technology.

After his retirement, Pinkerton was an independent consultant until his sudden death. He was editor of a series of professional computer books, and was editor of ICL's respected research journal. He was a liveryman of the Guild of Information Technologists, and worked hard for its apprenticeship scheme.

John Maurice McClean Pinkerton, computer engineer: born London 2 August 1919; married 1948 Helen McCorkindale (one son, one daughter); died London 22 December 1997.