The LEO I (Lyons Electronic Office I) was the first

computer A computer is a machine that can be programmed to Execution (computing), carry out sequences of arithmetic or logical operations (computation) automatically. Modern digital electronic computers can perform generic sets of operations known as C ...

used for commercial business applications. The prototype LEO I was modelled closely on the

Cambridge Cambridge ( ) is a university city and the county town in Cambridgeshire, England. It is located on the River Cam approximately north of London. As of the 2021 United Kingdom census, the population of Cambridge was 145,700. Cambridge bec ...

EDSAC The Electronic Delay Storage Automatic Calculator (EDSAC) was an early British computer. Inspired by John von Neumann's seminal ''First Draft of a Report on the EDVAC'', the machine was constructed by Maurice Wilkes and his team at the Universi ...

. Its construction was overseen by Oliver Standingford, Raymond Thompson and David Caminer of J. Lyons and Co. LEO I ran its first business application in 1951. In 1954 Lyons formed LEO Computers Ltd to market LEO I and its successors LEO II and LEO III to other companies. LEO Computers eventually became part of

English Electric Company N.º UIC: 9094 110 1449-3 (Takargo Rail) The English Electric Company Limited (EE) was a British industrial manufacturer formed after the Armistice of 11 November 1918, armistice of World War I by amalgamating five businesses which, during th ...

(EEL), (EELM), then English Electric Computers (EEC), where the same team developed the faster LEO 360 and even faster LEO 326 models. It then passed to

International Computers Limited International Computers Limited (ICL) was a British computer hardware, computer software and computer services company that operated from 1968 until 2002. It was formed through a merger of International Computers and Tabulators (ICT), English Ele ...

(ICL) and ultimately

Fujitsu is a Japanese multinational information and communications technology equipment and services corporation, established in 1935 and headquartered in Tokyo. Fujitsu is the world's sixth-largest IT services provider by annual revenue, and the la ...

. LEO series computers were still in use until 1981.

Origins and initial design

J. Lyons and Co. J. Lyons & Co. was a British restaurant Chain store, chain, food manufacturing, and hotel conglomerate founded in 1884 by Joseph Lyons (caterer), Joseph Lyons and his brothers in law, Isidore Gluckstein, Isidore and Montague Gluckstein. Lyons’ ...

was one of the UK's leading catering and food manufacturing companies in the first half of the 20th century. In 1947, they sent two of its senior managers, Oliver Standingford and Raymond Thompson, to the US to look at new business methods developed during

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...

. During the visit, they met

Herman Goldstine Herman Heine Goldstine (September 13, 1913 – June 16, 2004) was a mathematician and computer scientist, who worked as the director of the IAS machine at Princeton University's Institute for Advanced Study and helped to develop ENIAC, the ...

who was one of the original developers of

ENIAC ENIAC (; Electronic Numerical Integrator and Computer) was the first programmable, electronic, general-purpose digital computer, completed in 1945. There were other computers that had these features, but the ENIAC had all of them in one packa ...

, the first general-purpose electronic computer. Standingford and Thompson saw the potential of computers to help solve the problem of administering a major business enterprise. They also learned from Goldstine that, back in the UK,

Douglas Hartree Douglas Rayner Hartree (27 March 1897 – 12 February 1958) was an English mathematician and physicist most famous for the development of numerical analysis and its application to the Hartree–Fock equations of atomic physics and the c ...

and

Maurice Wilkes Sir Maurice Vincent Wilkes (26 June 1913 – 29 November 2010) was a British computer scientist who designed and helped build the Electronic Delay Storage Automatic Calculator (EDSAC), one of the earliest stored program computers, and who inv ...

were actually building another such machine, the pioneering

computer, at the

University of Cambridge , mottoeng = Literal: From here, light and sacred draughts. Non literal: From this place, we gain enlightenment and precious knowledge. , established = , other_name = The Chancellor, Masters and Schola ...

. On their return to the UK, Standingford and Thompson visited Hartree and Wilkes in Cambridge and were favourably impressed with their technical expertise and vision. Hartree and Wilkes estimated that EDSAC was twelve to eighteen months from completion, but said that this timeline could be shortened if additional funding were available. Standingford and Thompson wrote a report to the Lyons' board recommending that Lyons should acquire or build a computer to meet their business needs. The board agreed that, as a first step, Lyons would provide Hartree and Wilkes with £2,500 funding (equivalent to £104,000 in 2022) for the EDSAC project, and would also provide them with the services of a Lyons electrical engineer, Ernest Lenaerts. EDSAC was completed and ran its first program in May 1949. Following the successful completion of EDSAC, the Lyons board agreed to start the construction of their own machine, expanding on the EDSAC design. The LEO computer room, which took up around 2,500 square feet of floor space, was at

Cadby Hall Cadby Hall was a major office and factory complex in Hammersmith, London which was the headquarters of catering company Joseph Lyons and Co. for almost a century. Origins The name originated from Charles Cadby, piano manufacturer, who purchased ...

in Hammersmith. The Lyons machine was christened Lyons Electronic Office, or LEO. On the recommendation of Wilkes, Lyons recruited

John Pinkerton John Pinkerton (17 February 1758 – 10 March 1826) was a Scottish antiquarian, cartographer, author, numismatist, historian, and early advocate of Germanic racial supremacy theory. He was born in Edinburgh, as one of three sons to ...

, a radar engineer and research student at Cambridge, as team leader for the project. Lenaerts returned to Lyons to work on the project, and Wilkes provided training for Lyons' engineer Derek Hemy, who would be responsible for writing LEO's programs. On 15 February 1951 the computer, carrying out a simple test program, was shown to

HRH Royal Highness is a style used to address or refer to some members of royal families, usually princes or princesses. Monarchs and their consorts are usually styled ''Majesty''. When used as a direct form of address, spoken or written, it takes ...

Princess Elizabeth. The first business application to be run on LEO was Bakery Valuations, which computed the costs of ingredients used in bread and cakes. This was successfully run on 5 September 1951, and LEO took over Bakery Valuations calculations completely on 29–30 November 1951.

Mary Coombs Mary Clare Coombs ( Blood, 4 February 1929 – 28 February 2022) was a British computer programmer and schoolteacher. Employed in 1952 as the first female programmer to work on the LEO computers, she is recognised as the first female commercia ...

was employed in 1952 as the first female programmer to work on LEO, and as such she is recognized as the first female commercial programmer. Five files of archive material on the LEO Computer patent are held at the

British Library The British Library is the national library of the United Kingdom and is one of the largest libraries in the world. It is estimated to contain between 170 and 200 million items from many countries. As a legal deposit library, the British ...

and can be accessed through the British Library catalogue.

Technical description

LEO I's clock speed was 500 kHz, with most instructions taking about 1.5 ms to execute. To be useful for business applications, the computer had to be able to handle a number of data streams, input and output, simultaneously. Therefore, its chief designer,

, designed the machine to have multiple input/output buffers. In the first instance, these were linked to fast

paper tape Five- and eight-hole punched paper tape Paper tape reader on the Harwell computer with a small piece of five-hole tape connected in a circle – creating a physical program loop Punched tape or perforated paper tape is a form of data storage ...

readers and punches, fast punched card readers and punches, and a 100 line a minute tabulator. Later, other devices, including magnetic tape, were added. Its ultrasonic

delay-line memory Delay-line memory is a form of computer memory, now obsolete, that was used on some of the earliest digital computers. Like many modern forms of electronic computer memory, delay-line memory was a refreshable memory, but as opposed to modern ran ...

based on tanks of

mercury Mercury commonly refers to: * Mercury (planet), the nearest planet to the Sun * Mercury (element), a metallic chemical element with the symbol Hg * Mercury (mythology), a Roman god Mercury or The Mercury may also refer to: Companies * Merc ...

, with 2K (2048) 35-bit words (i.e., 8

kilobyte The kilobyte is a multiple of the unit byte for digital information. The International System of Units (SI) defines the prefix ''kilo'' as 1000 (103); per this definition, one kilobyte is 1000 bytes.International Standard IEC 80000-13 Quantiti ...

s), was four times as large as that of EDSAC. The systems analysis was carried out by David Caminer.

Applications and successors

Lyons used LEO I initially for valuation jobs, but its role was extended to include

payroll A payroll is the list of employees of some company that is entitled to receive payments as well as other work benefits and the amounts that each should receive. Along with the amounts that each employee should receive for time worked or tasks pe ...

inventory Inventory (American English) or stock (British English) refers to the goods and materials that a business holds for the ultimate goal of resale, production or utilisation. Inventory management is a discipline primarily about specifying the shap ...

, and so on. One of its early tasks was the elaboration of daily orders which were phoned in every afternoon by the shops and used to calculate the overnight production requirements, assembly instructions, delivery schedules, invoices, costings, and management reports. This was the first instance of an integrated management information system. The LEO project was also a pioneer in

outsourcing Outsourcing is an agreement in which one company hires another company to be responsible for a planned or existing activity which otherwise is or could be carried out internally, i.e. in-house, and sometimes involves transferring employees and ...

: in 1956, Lyons started doing the payroll calculations for Ford UK and others on the LEO I machine. The success of this led to the company dedicating one of its LEO II machines to bureau services. Later, the system was used for scientific computations as well.

Met Office The Meteorological Office, abbreviated as the Met Office, is the United Kingdom's national weather service. It is an executive agency and trading fund of the Department for Business, Energy and Industrial Strategy and is led by CEO Penelope E ...

staff used a LEO I before the Met Office bought its own computer, a

Ferranti Mercury The Mercury was an early commercial computer from the mid-1950s built by Ferranti. It was the successor to the Ferranti Mark 1, adding a floating point unit for improved performance, and increased reliability by replacing the Williams tube memory w ...

, in 1959. In 1954, with the decision to proceed with LEO II and interest from other commercial companies, Lyons formed LEO Computers Ltd.

LEO III

The first LEO III was completed in 1961; it was a solid-state machine with a 13.2 μs cycle time ferrite core memory. It was microprogrammed and was controlled by a multitasking "Master program" operating system, which allowed concurrent running of as many as 12 application programs. Users of LEO computers programmed in two coding languages: Intercode, a low-level

assembler Assembler may refer to: Arts and media * Nobukazu Takemura, avant-garde electronic musician, stage name Assembler * Assemblers, a fictional race in the ''Star Wars'' universe * Assemblers, an alternative name of the superhero group Champions of ...

type language; and CLEO (

acronym An acronym is a word or name formed from the initial components of a longer name or phrase. Acronyms are usually formed from the initial letters of words, as in ''NATO'' (''North Atlantic Treaty Organization''), but sometimes use syllables, as ...

: Clear Language for Expressing Orders), the

COBOL COBOL (; an acronym for "common business-oriented language") is a compiled English-like computer programming language designed for business use. It is an imperative, procedural and, since 2002, object-oriented language. COBOL is primarily us ...

equivalent. One of the features that LEO III shared with many computers of the day was a loudspeaker connected to the central processor via a divide by 100 circuit and an amplifier which enabled operators to tell whether a program was looping by the distinctive sound it made. Another quirk was that many intermittent faults were due to faulty connectors and could be temporarily fixed by briskly strumming the card handles. Some LEO III machines purchased in the mid-to-late 1960s remained in commercial use at

GPO GPO may refer to: Government and politics * General Post Office, Dublin * General Post Office, in Britain * Social Security Government Pension Offset, a provision reducing benefits * Government Pharmaceutical Organization, a Thai state enterpris ...

Telephones, the forerunner of

British Telecom BT Group plc (trade name, trading as BT and formerly British Telecom) is a British Multinational corporation, multinational telecommunications holding company headquartered in London, England. It has operations in around 180 countries and is th ...

, until 1981, primarily producing telephone bills. They were kept running using parts from redundant LEOs purchased by the GPO.

Fate of the company

In 1963, LEO Computers Ltd was merged into

and this led to the breaking up of the team that had inspired LEO computers. The company continued to build the LEO III, and went on to build the faster LEO 360 and even faster LEO 326 models, which had been designed by the LEO team before the takeover. English Electric LEO Computers (EEL) (1963), then English Electric Leo Marconi (EELM) (1964), later English Electric Computers (EEC) (1967), eventually merged with

International Computers and Tabulators International Computers and Tabulators or ICT was a British computer manufacturer, formed in 1959 by a merger of the British Tabulating Machine Company (BTM) and Powers-Samas. In 1963 it acquired the business computer divisions of Ferranti. It ...

(ICT) and others to form

(ICL) in 1968. In the 1980s, there were still ICL 2900 mainframes running LEO programs, using an emulator written in ICL 2960 microcode at the

Dalkeith Dalkeith ( ; gd, Dail Cheith, IPA: �t̪alˈçe is a town in Midlothian, Scotland, on the River Esk. It was granted a burgh of barony in 1401 and a burgh of regality in 1540. The settlement of Dalkeith grew southwestwards from its 12th-cent ...

development centre. At least one modern emulator has been developed which can run some original LEO III software on a modern server. ICL was bought by

in 1990.

Legacy

Whether its investment in LEO actually benefited J. Lyons is unclear.

Nick Pelling Nick Pelling is a British-born computer programmer and investigative writer best known as the creator of the 1984 game '' Frak!''."Desert Island Disks: Nick Pelling". ''Retro Gamer'' 26, pp. 82-85. Games Developed As Aardvark Software ...

notes that before LEO I the company already had a proven, industry-leading system using clerks that gave it "near-real-time management information on more or less all aspects of its business", and that no jobs were lost when the system was computerized. In addition, LEO Computers lost money on many of its sales because of unrealistically low prices. In 2018, The

Centre for Computing History The Centre for Computing History is a museum in Cambridge, England, established to create a permanent public exhibition telling the story of the Information Age. Overview The museum acts as a repository for vintage computers and related artefa ...

along with LEO Computers Society were awarded funding from the

Heritage Lottery Fund The National Lottery Heritage Fund, formerly the Heritage Lottery Fund (HLF), distributes a share of National Lottery funding, supporting a wide range of heritage projects across the United Kingdom. History The fund's predecessor bodies were ...

for their project aiming to bring together, preserve, archive and digitise a range of LEO Computers artefacts, and documents. The Centre's museum gallery has an area dedicated to LEO, and they are also working on a LEO

virtual reality Virtual reality (VR) is a simulated experience that employs pose tracking and 3D near-eye displays to give the user an immersive feel of a virtual world. Applications of virtual reality include entertainment (particularly video games), educ ...

project. In November 2021, to coincide with the 70th anniversary of the first successful full program run on LEO I, the project released a film about the history of LEO, which went on to win Video of the Year in the Association of British Science Writers Awards in July 2022.

References

External links

LEO Computers Society
Includes
LEOPEDIA
' which is intended to be a comprehensive reference to archive, museum and media holdings and references to LEO computers, and individuals associated with them, updated periodically by

Frank Land Fred Frank Land (born Frank Landsberger; October 1928) is a German-born information systems researcher and was the first United Kingdom Professor of Information Systems. He is currently emeritus professor in the Department of Information Syst ...

.
LEO Magnetic Data Tape Collection at The ICL Computer Museum

LEO Artefacts at The ICL Computer Museum

LEO Paperwork at The ICL Computer Museum

LEO Artefacts at the Centre for Computing History

LEO Computers Collection
National Archive for the History of Computing,

University of Manchester Library The University of Manchester Library is the library system and information service of the University of Manchester. The main library is on the Oxford Road campus of the university, with its entrance on Burlington Street. There are also ten other ...

.
How a cake company pioneered the first office computer
BBC video interview with

, who worked on the first LEO computer and was the first woman to become a commercial computer programmer
Oral history interview with John M. M. Pinkerton

Charles Babbage Institute The IT History Society (ITHS) is an organization that supports the history and scholarship of information technology by encouraging, fostering, and facilitating archival and historical research. Formerly known as the Charles Babbage Foundation, ...

, University of Minnesota. Pinkerton describes his work on LEO computers. In this context he discusses the British computer firms J. Lyons and Company,

English Electric N.º UIC: 9094 110 1449-3 (Takargo Rail) The English Electric Company Limited (EE) was a British industrial manufacturer formed after the Armistice of 11 November 1918, armistice of World War I by amalgamating five businesses which, during th ...

, and International Computers Ltd.
About LEO
– From ''Business Computing: the Second 50 Years'', The Guildhall conference for business leaders, London, 2001. Archived in February 2012.

Extract from Peter Bird's ''LEO – The First Business Computer'' (2002); at David Lawrence's Lyons website
BBC Science: Electronic Brains
BBC Radio 4 series about early computers, 2002; programme 1 is about LEO
''Hidden Histories of the Information Age''
BBC Radio 4 series, 2016; programme about LEO
"Developing LEO: The world's first business computer", documents from the papers of John Simmons, Modern Records Centre, University of Warwick
* * * {{ICL hardware Early British computers ICL mainframe computers Vacuum tube computers Computer-related introductions in 1951 History of software Outsourcing Supply chain management University of Cambridge Computer Laboratory Serial computers

Origins and initial design

Technical description

Applications and successors

LEO III

Fate of the company

Legacy

See also

References

Further reading

Books

Articles

External links