Polish Enigma doubles

*Biuro Szyfrów*
Methods and technology
"ANX" · Enigma "doubles" · Grill Clock · Cyclometer · Card catalog Cryptologic bomb Zygalski sheets · Lacida
Locations
Saxon Palace · Kabaty Woods PC Bruno · Cadix
Personnel
Chief Gwido Langer Deputy Chief Chief of Radio Intelligence Chief of German Section Maksymilian Ciężki German Section cryptologists Marian Rejewski · Jerzy Różycki Henryk Zygalski · Antoni Palluth Wiktor Michałowski Chief of Russian Section Jan Graliński Russian Section cryptologist Piotr Smoleński Others Jan Kowalewski Stanisław Leśniewski Stefan Mazurkiewicz Franciszek Pokorny Wacław Sierpiński

The Enigma cipher machine

Enigma machine Enigma rotors Breaking Enigma Polish Cipher Bureau Doubles Grill Clock Cyclometer Bomba Zygalski sheets Bletchley Park Banburismus Herivel tip Crib Bombe Hut 6 Hut 8 PC Bruno Ultra

Enigma "doubles" were machines produced by the Polish Cipher Bureau, based on Marian Rejewski's reconstruction of the German Enigma machine's wirings.^[1]

1 Built in Poland
2 Precious gift
3 Built in France
4 See also
5 Notes
6 References

Built in Poland

In February 1933, the Polish Cipher Bureau ordered fifteen "doubles" of the military Enigma machine from the AVA Radio Manufacturing Company, in Warsaw.^[2] Ultimately, about seventy such units would be produced.

Precious gift

In 1939, two Enigma doubles were sent to Paris and London.^[3] Until then, German military Enigma traffic had defeated the British and French, and they had faced the disturbing prospect that German communications would remain "black" to them for the duration of the coming war.

Built in France

After Germany invaded Poland in September 1939 and key Polish Cipher Bureau personnel evacuated to France, the Cipher Bureau resumed its interrupted work at PC Bruno, outside Paris. The Poles had only three Enigma doubles to work with,^[4] and these were wearing out from round-the-clock use. French Army intelligence officer Gustave Bertrand ordered parts for forty doubles from a French precision-mechanics firm. Manufacture proceeded sluggishly, however, and it was only after the fall of France and the opening of underground work in southern France's Free Zone in October 1940 that four machines were finally assembled.^[5]

Notes

^ Woytak, "A Conversation with Marian Rejewski," pp. 53–55.
^ Kozaczuk, Enigma, p. 25.
^ Kozaczuk, Enigma, pp. 59–60.
^ Kozaczuk, Enigma, p. 83. Two secretly taken out of Poland during the evacuation, and the one that had been sent to France after the July 25, 1939, tripartite Warsaw conference.
^ Kozaczuk, Enigma, pp. 84–85.

References

Brzezinski, Zbigniew (2005). "The Unknown Victors". Marian Rejewski, 1905-1980: Living with the Enigma Secret. Bydgoszcz: Bydgoszcz City Council. pp. 15–18. ISBN 8372081174. OCLC 62701914.
Kozaczuk, Władysław; edited and translated by Christopher Kasparek (1984). Enigma: How the German Machine Cipher Was Broken, and How It Was Read by the Allies in World War Two. Foreign intelligence book series. Frederick, Md.: University Publications of America. ISBN 0890935475. OCLC 9826775.
Woytak, Richard A.; transcribed and translated by Christopher Kasparek (January 1982). "A Conversation with Marian Rejewski". Cryptologia 6 (1): 50–60. doi:10.1080/0161-118291856830.