__NOTOC__ The British Tabulating Machine Company (BTM) was a firm which manufactured and sold Hollerith

unit record equipment Starting at the end of the nineteenth century, well before the advent of electronic computers, data processing was performed using Electromechanics, electromechanical machines collectively referred to as unit record equipment, electric accounting ...

and other data-processing equipment. During

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

, BTM constructed some 200 "

bombe The bombe () was an Electromechanics, electro-mechanical device used by British cryptologists to help decipher German Enigma machine, Enigma-machine-encrypted secret messages during World War II. The United States Navy, US Navy and United Sta ...

s", machines used at

Bletchley Park Bletchley Park is an English country house and Bletchley Park estate, estate in Bletchley, Milton Keynes (Buckinghamshire), that became the principal centre of Allies of World War II, Allied World War II cryptography, code-breaking during the S ...

to break the German

Enigma machine The Enigma machine is a cipher device developed and used in the early- to mid-20th century to protect commercial, diplomatic, and military communication. It was employed extensively by Nazi Germany during World War II, in all branches of the W ...

ciphers.

History

The company was formed in 1902 as The Tabulator Limited, after Robert Porter obtained the rights to sell

Herman Hollerith Herman Hollerith (February 29, 1860 – November 17, 1929) was a German-American statistician, inventor, and businessman who developed an electromechanical tabulating machine for punched cards to assist in summarizing information and, later, in ...

's patented machines from the US Tabulating Machine Company (later to become

IBM International Business Machines Corporation (using the trademark IBM), nicknamed Big Blue, is an American Multinational corporation, multinational technology company headquartered in Armonk, New York, and present in over 175 countries. It is ...

). 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

, was initially conceived by

Alan Turing Alan Mathison Turing (; 23 June 1912 – 7 June 1954) was an English mathematician, computer scientist, logician, cryptanalyst, philosopher and theoretical biologist. He was highly influential in the development of theoretical computer ...

, 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. By the end of the European war, over two hundred bombes had been built and installed.

HEC computer

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. 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. The HEC 4 was also known as the BTM 1201 (or 1202 with a bigger drum) and later as the ICT 1201, and was exported as far as New Zealand.

Merger

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 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), which was later taken over by Fujitsu.

References

* John Harper, BTM – British Tabulating Machine Company Limite

(archived 1 December 2010). * John Keen, Harold 'Doc' Keen and the Bletchley Park Bombe, 2003, . * Martin Campbell-Kelly, ICL and the British computer industry

*

External links

Letchworth's Enigma

(archived 4 December 2013)
Grace's Guide to British Industrial History – British Tabulating Machine Co

The BTM HOLLERITH Paperwork Collection at The ICL Computer Museum

The BTM HEC Paperwork Collection at The ICL Computer Museum
{{Authority control Defunct manufacturing companies of the United Kingdom International Computers Limited Cryptanalytic devices Manufacturing companies established in 1902 1902 establishments in England British companies established in 1902 British companies disestablished in 1959 1959 disestablishments in England