The first ever business computer, LEO I, operated by British tea-shop company J Lyons, ran its first program — to calculate the week's value of cakes, bread and pies — on 17 November, 1951.
J Lyons has been seen as an unlikely candidate to be the first business to run a commercial computer, given that it was not heavily involved with electronics manufacturing, and its primary business was serving tea-shop customers.
Nevertheless, the company had the DNA to embark on an ambitious project that would change the nature of how businesses used computers. Frank Land, who was involved with the project, told the BBC Radio 4 Today programme that J Lyons was "a smart company" that was "always looking at its business processes".
The perishable nature of many of J Lyons's products, plus its tight operating margins, led the company to consider innovative ways of tracking its business processes, according to David C Mowery of UC Berkeley.
In the 1920s, J Lyons created the 'Organisation and Methods' group, headed by Cambridge maths graduate JRM Simmons, to look at accounting and production processes, and business equipment. Simmons rose to become a board director and J Lyons' senior executive.
In 1947, Simmons sent two J Lyons executives who were interested in the business application of computers, TR Thompson and Oliver Standingford, to the US on a fact-finding mission (the pioneering computing advances made in the UK by code-breakers such as Alan Turing at Bletchley Park remained under wraps at the time due to security concerns). Thompson and Standingford learned about ENIAC, the first all-electronic computer, on a visit to the University of Pennsylvania.
Back in the UK, they also visited Cambridge University, according to the Staffordshire University Computing Futures Museum. At Cambridge, Thompson and Standingford met Maurice Wilkes, who was part of a team busy designing a computer known as EDSAC. In exchange for financial help to complete EDSAC, Wilkes agreed to help J Lyons with the design of the Lyons Electronic Office (LEO) computer, which drew on the EDSAC design.
In January 1949 engineer John Pinkerton joined J Lyons, and was involved in setting up a workshop at Cadby Hall to experiment with circuits. This picture shows Lyons engineers Gordon Gibbs and Ray Shawlook looking at a LEO circuit diagram in February 1950.
LEO I filled a large room and used 5,936 valves, with another 300-400 in auxiliary equipment, according to the LSE. LEO used 64 mercury tubes — each over five feet in length — for storage, each tube weighing half a ton. The components were assembled in racks to minimise the impact of equipment failure — engineers had to replace up to 50 valves per week during times of heavy failure rates.
This picture shows the LEO I built at Cadby Hall in Hammersmith.
LEO I had multiple input/output buffers — for punched card reader, paper tape reader, card punch and printer. The mercury tubes for LEO I held 8.75 kilobytes of data.
LEO coders programmed in two languages: Intercode, a low-level assembler language, and Clear Language for Expressing Orders (Cleo), which was like Cobol, according to the Staffordshire University Computing Futures Museum.
LEO had a speaker installed, which allowed engineers to aurally monitor certain calculations.
LEO I was initially used for evaluation, but eventually its role was extended to include functions such as payroll, inventory and production management.
This picture shows the LEO I control desk.
In the first two thirds of the 20th century, the UK's monetary system was calculated in pounds, shillings and pence — which was a base-10, base-20 and base-12 system, rather than decimalised. Simmons had created a mechanical calculator which used pounds and decimal fractions of a pound, because a multi-base currency made machine calculation challenging.
Pictured above is one of Leo's decimal/sterling binary converters, which it used to get around the problem of multi-base calculation.
LEO 1 became a model for outsourcing, being used by Ford UK and the Met Office for computing jobs. In November 1954 Lyons formed Leo Computers Ltd to build business computers to order, producing the LEO II in 1957. Organisations that used LEO II computers included Stewarts & Lloyds, Ford and the Ministry of Pensions.
This picture shows Peter Wood at the tabulator and Kate Keene at the control desk, at the LEO II / I at J Lyons & Co Ltd, Elms House, Hammersmith.
The first LEO III, micro-programmed and controlled by a multi-tasking operating system, was completed in 1961. It was a solid-state machine with a ferrite core memory.
LEO III machines were used by organisations including Dunlop Rubber Company, Shell-Mex & BP Ltd, HM Customs & Excise and H J Heinz Co Ltd.
In 1963, Leo Computers Ltd merged with the English Electric Company. In 1968, English Electric LEO Marconi merged with International Computers and Tabulators (ICT) and others to form International Computers Limited (ICL).
Some LEO IIIs were still in commercial use with GPO Telephones, the forerunner of British Telecom, in 1981. Engineers kept them running through replacement parts from redundant LEOs purchased by the GPO.
This picture shows LEO III / 6 at Shell-Mex & BP Ltd, Hemel Hempstead.
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