Polish Bomba
“...to [the Polish cryptologists] alone belongs all the credit and all the glory for having successfully carried through this incredible technical feat, thanks to their knowledge and perseverance, unequalled in any country in the world. They overcame difficulties that the Germans had thought ‘insurmountable,’ of which it is hard to give an idea.”
-Bertrand Renard, France's Chief of the Bureu des Chiffres (French Treasury)
"Denniston" 1940
Source: gchq.gov.uk
"Mathematicians of the Polish Intelligence Service were the first to break the Enigma code. In July 1939 [they] passed over to British Intelligence a copy of the Enigma machine and the fruits of their work done in breaking the code in the years 1932-1939. This work greatly assisted the Bletchley Park codebreakers and contributed to the Allied victory in World War two."
-Missive from the Federation of Poles in Great Britain
Just before WWII, British intelligence officers Alastair Denniston and Dilly Knox visited the secret PCB station at Pyry. The two countries exchanged Enigma information and research concerning the Bomba machine. The sharing of Polish information with the British intelligence officers provided the foundation for Britain’s later work on deciphering the Enigma code.
After WWI, Poland still considered Germany a major threat, so the Polish Cipher Bureau (PCB) immediately began manually deciphering Enigma codes after intercepting encoded radio messages. In 1932, Poland successfully replicated an Enigma machine, but could not decipher the code fast enough. To break this barrier, they created the first electro-mechanical code breaking device: the Bomba machine. In 1932, the Poles succeeded in breaking the Enigma code; however, in 1938, while preparing for WWII, Germany increased the complexity of its military Enigma, rendering the Polish Bomba obsolete.
"The most important service the Poles ever rendered to the anti-Nazi cause, was something they did before the war had even begun."
-Cambridge Professor Michael Richard Daniell Foot, British military historian and British Army intelligence officer
"Alfred Dillwyn (Dilly) Knox" 1940
Source: cryptomuseum.com
Creating the Barrier
British Bombe