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The British Tabulating Machine Company (BTM) was a firm which manufactured and sold Hollerith unit record equipment and other data-processing equipment. During World War II, BTM constructed some 200 "bombes", machines used at Bletchley Park to break the German Enigma machine ciphers.
The company was formed in 1902 as The Tabulator Limited, after Robert Porter obtained the rights to sell Herman Hollerith's patented machines from the US Tabulating Machine Company (later to become IBM). During 1907, the company was renamed the "British Tabulating Machine Company Limited". In 1920, the company moved from London to Letchworth, Hertfordshire; it was also at this point that it started manufacturing its own machines, rather than simply reselling Hollerith equipment.
Annual revenues were £6K in 1915, £122K in 1925, and £170K in 1937. In 1916 there were 45 staff; this increased to 132 in 1922, 326 in 1929 and 1,225 in 1939.
In return for the exclusive right to market Hollerith equipment in Britain and the Empire (excluding Canada), BTM paid 25% of its revenues to the American company by way of royalties. This became an ever-increasing burden as the years progressed; BTM attempted to renegotiate the agreement on several occasions, but it was only finally terminated in 1948.
During World War II, BTM was called upon to design and manufacture a machine to assist breaking the German Enigma machine ciphers. This machine, known as a bombe, was initially conceived by Alan Turing, but the actual machine was designed by BTM chief engineer Harold 'Doc' Keen, who had led the company's engineering department throughout the 1930s. The project was codenamed "CANTAB". The project was managed by computing pioneer Dora Metcalf until 1942. [1] [2] By the end of the European war, over two hundred bombes had been built and installed.
BTM built a valve based computer called the Hollerith Electronic Computer (HEC). The first model (HEC 1) was built in 1951, an example is held by the Birmingham Museum. [3] [4] [5] BTM went on to develop the HEC 2, 2M and 4 models, eventually building more than 100. The machines had a 2 kilobyte drum memory and 1000 valves, and could use punched cards for input and output, or drive a printer. [6] [7]
In 1959 BTM merged with former rival Powers-Samas to become International Computers and Tabulators Limited (ICT). ICT later became part of International Computers Limited (ICL), which was later taken over by Fujitsu.
Herman Hollerith was an American statistician, inventor, and businessman who developed an electromechanical tabulating machine for punched cards to assist in summarizing information and, later, in accounting. His invention of the punched card tabulating machine, patented in 1884, marks the beginning of the era of mechanized binary code and semiautomatic data processing systems, and his concept dominated that landscape for nearly a century.
A punched card is a piece of card stock that stores digital data using punched holes. Punched cards were once common in data processing and the control of automated machines.
Electronic data processing (EDP) or business information processing can refer to the use of automated methods to process commercial data. Typically, this uses relatively simple, repetitive activities to process large volumes of similar information. For example: stock updates applied to an inventory, banking transactions applied to account and customer master files, booking and ticketing transactions to an airline's reservation system, billing for utility services. The modifier "electronic" or "automatic" was used with "data processing" (DP), especially c. 1960, to distinguish human clerical data processing from that done by computer.
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 Electric Computers (EEC) and Elliott Automation in 1968. The company's most successful product line was the ICL 2900 Series range of mainframe computers.
The bombe was an electro-mechanical device used by British cryptologists to help decipher German Enigma-machine-encrypted secret messages during World War II. The US Navy and US Army later produced their own machines to the same functional specification, albeit engineered differently both from each other and from Polish and British bombes.
Thomas Harold Flowers MBE was an English engineer with the British General Post Office. During World War II, Flowers designed and built Colossus, the world's first programmable electronic computer, to help decipher encrypted German messages.
The Powers Accounting Machine was an information processing device developed in the early 20th century for the U.S. Census Bureau. It was then produced and marketed by the Powers Accounting Machine Company, an information technology company founded by the machine's developer. The company thrived in the early 20th century as a producer of tabulating machines. It was a predecessor to the Unisys corporation.
Starting at the end of the nineteenth century, well before the advent of electronic computers, data processing was performed using electromechanical machines collectively referred to as unit record equipment, electric accounting machines (EAM) or tabulating machines. Unit record machines came to be as ubiquitous in industry and government in the first two-thirds of the twentieth century as computers became in the last third. They allowed large volume, sophisticated data-processing tasks to be accomplished before electronic computers were invented and while they were still in their infancy. This data processing was accomplished by processing punched cards through various unit record machines in a carefully choreographed progression. This progression, or flow, from machine to machine was often planned and documented with detailed flowcharts that used standardized symbols for documents and the various machine functions. All but the earliest machines had high-speed mechanical feeders to process cards at rates from around 100 to 2,000 per minute, sensing punched holes with mechanical, electrical, or, later, optical sensors. The operation of many machines was directed by the use of a removable plugboard, control panel, or connection box. Initially all machines were manual or electromechanical. The first use of an electronic component was in 1937 when a photocell was used in a Social Security bill-feed machine. Electronic components were used on other machines beginning in the late 1940s.
Cryptanalysis of the Enigma ciphering system enabled the western Allies in World War II to read substantial amounts of Morse-coded radio communications of the Axis powers that had been enciphered using Enigma machines. This yielded military intelligence which, along with that from other decrypted Axis radio and teleprinter transmissions, was given the codename Ultra.
Harold Hall "Doc" Keen (1894–1973) was a British engineer who produced the engineering design, and oversaw the construction of, the British bombe, a codebreaking machine used in World War II to read German messages sent using the Enigma machine. He was known as "Doc" Keen because of his habit of carrying tools and paperwork in a case resembling a doctor's bag. After the war he was awarded the O.B.E.
The tabulating machine was an electromechanical machine designed to assist in summarizing information stored on punched cards. Invented by Herman Hollerith, the machine was developed to help process data for the 1890 U.S. Census. Later models were widely used for business applications such as accounting and inventory control. It spawned a class of machines, known as unit record equipment, and the data processing industry.
The APE(X)C, or All Purpose Electronic (X) Computer series was designed by Andrew Donald Booth at Birkbeck College, London in the early 1950s. His work on the APE(X)C series was sponsored by the British Rayon Research Association. Although the naming conventions are slightly unclear, it seems the first model belonged to the BRRA. According to Booth, the X stood for X-company.
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 exported computers to many countries and in 1968 became part of International Computers Limited (ICL).
The ICT 1301 and its smaller derivative ICT 1300 were early business computers from International Computers and Tabulators. Typical of mid-sized machines of the era, they used core memory, drum storage and punched cards, but they were unusual in that they were based on decimal logic instead of binary.
Powers-Samas was a British company which sold unit record equipment.
The National Museum of Computing is a UK-based museum that is dedicated to collecting and restoring historic computer systems, and is home to the world's largest collection of working historic computers. The museum is located on Bletchley Park in Milton Keynes, Buckinghamshire. It opened in 2007 in Block H – the first purpose-built computer centre in the world, having housed six of the ten Colossus computers that were in use at the end of World War II.
John Harper is a retired computer engineer. He led a Computer Conservation Society/Bletchley Park team that rebuilt a working World War II electromechanical Bombe decryption device.
The Hollerith Electronic Computer (HEC) was produced by the British Tabulating Machine Company (BTM) and was based on a design by Professor Andrew Booth of Birkbeck College, London. It was Britain's first mass-produced business computer. The prototype first worked at the end of 1951.
James Legrand Powers was a US inventor and entrepreneur, the founder of Powers Accounting Machine Company.
Dora Stuart Primrose Metcalf was an India-born Irish entrepreneur, mathematician and computing pioneer. During World War I she was a comptometer operator in a munitions factory during which time she realised the potential in the mechanical descendants of the abacus. During World War II she was involved with supplying the "bombe" decryption machines to the codebreakers at Bletchley Park in England.
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