Ralph Paterson Tester (2 June 1902 – May 1998) was an administrator 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 ...

, the British

codebreaking Cryptanalysis (from the Greek ''kryptós'', "hidden", and ''analýein'', "to analyze") refers to the process of analyzing information systems in order to understand hidden aspects of the systems. Cryptanalysis is used to breach cryptographic secu ...

station 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 ...

. He founded and supervised a section named the '' Testery'' for breaking Tunny (a

Fish A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...

cipher).

Background

The

Lorenz cipher The Lorenz SZ40, SZ42a and SZ42b were German Rotor machine, rotor stream cipher machines used by the German Army (Wehrmacht), German Army during World War II. They were developed by C. Lorenz AG in Berlin. The model name ''SZ'' is derived from ' ...

machine had twelve wheels, and was thus most advanced, complex, faster and far more secure than the three-wheeled Enigma. Lorenz was used to encipher top-secret messages between German Army H.Q. in

Berlin Berlin ( ; ) is the Capital of Germany, capital and largest city of Germany, by both area and List of cities in Germany by population, population. With 3.7 million inhabitants, it has the List of cities in the European Union by population withi ...

, and the top generals and field-marshals on all fronts, including

Adolf Hitler Adolf Hitler (20 April 1889 – 30 April 1945) was an Austrian-born German politician who was the dictator of Nazi Germany from 1933 until Death of Adolf Hitler, his suicide in 1945. Adolf Hitler's rise to power, He rose to power as the lea ...

himself.

Career

Before World War II, Tester was an

accountant An accountant is a practitioner of accounting or accountancy. Accountants who have demonstrated competency through their professional associations' certification exams are certified to use titles such as Chartered Accountant, Chartered Certif ...

who had worked extensively in

Germany Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...

and as a result was very familiar with the

German language German (, ) is a West Germanic language in the Indo-European language family, mainly spoken in Western Europe, Western and Central Europe. It is the majority and Official language, official (or co-official) language in Germany, Austria, Switze ...

and culture.Paul Gannon, ''Colossus: Bletchley Park's Greatest Secret'', 2006, p. 168, Atlantic Books, . He held a senior position in the accountancy division of

Unilever Unilever PLC () is a British multinational consumer packaged goods company headquartered in London, England. It was founded on 2 September 1929 following the merger of Dutch margarine producer Margarine Unie with British soap maker Lever B ...

. On the outbreak of war, he worked for the BBC Monitoring Service which listened in to German public radio broadcasts.

Bletchley Park

Tester was recruited to Bletchley Park, and during later 1941 became the head of a small group working on a double Playfair cipher used by German military police. The Testery was set up in July 1942 under his command. The three other original founding members,

cryptographers This is a list of cryptographers. Cryptography is the practice and study of techniques for secure communication in the presence of third parties called adversaries. Pre twentieth century * Al-Khalil ibn Ahmad al-Farahidi: wrote a (now lost) book ...

and linguists, were: Capt.

Jerry Roberts Captain Raymond C. "Jerry" Roberts MBE (18 November 1920 – 25 March 2014) was a British wartime codebreaker and businessman. During the Second World War, Roberts worked at the Government Code and Cypher School at Bletchley Park from 194 ...

, Peter Ericsson and Maj. Denis Oswald. All four were fluent in German. The Testery used hand methods to break messages enciphered on Tunny traffic. The Testery decoded 1.5 million messages by hand within one year of its foundation. By the war's end in May 1945, the Testery had grown to nine cryptographers, with a total staff of 118 organised in three shifts. A former Testery senior codebreaker and shift leader

, recalls that, "The imperturbable, pipe-smoking Tester spoke fluent German, but did not pretend to be a codebreaker. The atmosphere in his unit was always positive and friendly, and the personnel were well selected—Tester seemed to find the right niche for everybody. Thanks to Tester's influence the work of the Testery was very well organised." Towards the end of the European war, Tester was part of a

TICOM TICOM (Target Intelligence Committee) was a secret Allied project formed in World War II to find and seize German intelligence assets, particularly in the field of cryptology and signals intelligence. It operated alongside other Western Allied ...

team, a mission sent to Germany to discover information about their communications technology, including TUNNY machines.Smith, ''Station X'', p. 203–204. After the war, Tester returned to Unilever.

References

{{DEFAULTSORT:Tester, Ralph British accountants Bletchley Park people Unilever people 1902 births 1998 deaths

Background

Career

Bletchley Park

See also

References