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Updated: 2 July 2013


Enigma - Page Two
(compiled from many sources including emails)

The geese that laid the most golden eggs - Churchill about his enimga staff

1. How Enigma Worked
2. Lorenze
3. Footnotes & Describing a Visit
4. Turing - Suicide or Accident
5. Ken Lacroix
6. Irgard Enge

How Enigma Worked

Messages transmitted to and from U-boats were intercepted in Britain by Royal Air Force 'listening' stations, known as 'Y' Stations. The 'Y' Stations also intercepted thousands of other enemy messages each day. Outside a 'Y' Station a forest of tall aerials picked up radio signals from as far away as the Soviet Union and Japan. Inside, a team of Morse code operators worked 24 hours a day, listening in to coded messages and writing them down. Your job would be to translate the Morse signals into letters and write them down as fast as you could - at least 90 letters a minute. If you made just ONE mistake it would be impossible for the code-breakers to break the code.

Bletchley Park was the home of the secret Government Code and Cypher School. This was the centre of British code-breaking during the war.  The code-breakers were specially chosen from among the cleverest people in the country. Some were brilliant mathematicians or linguists. On the left above is Alan Turing, a Cambridge mathematician and code-breaker who helped to invent the world's first computer (Colossus) at Bletchley Park. By 1944 they had a big team to help them. Seven thousand men and women worked in shifts round the clock in small wooden or concrete buildings known as 'Huts'. Many did repetitive but important jobs like filing or operating the code-breaking machines. They were not allowed to tell anyone - not even their family or friends - about their work. On average more than 3,000 coded messages arrived at Bletchley Park each day from the 'Y' Stations. Messages were taken to different 'Huts', depending on whether they had come from the German army, air force, navy or another source. A message from a U-boat would go to Hut 8. There the code-breakers would study it. The only way they could break the code was to compare the message with others to see if they could work out exactly how the U-boat commanders had set their Enigma rotor wheels and plug board settings that day. Imagine their task - to find the RIGHT ANSWER out of 150,000,000,000,000,000,000 POSSIBILITIES - and start all over again every 24 hours. Sometimes messages began with the same words, such as a weather report. This gave clues (called a CRIB) about how the rest of the message had been encoded. When the code-breakers eventually worked out what the CRIB letters might be, they tested them on the machine shown below, called a BOMBE. (Invented by Turing) Bombes were huge, noisy electro-mechanical machines which could check through combinations of letters far quicker than a human being could. When the Bombe stopped, this meant that the code-breakers' guesses were right. All that days U-boat messages could then be decoded.

Sometimes a code could be cracked in less than an hour. But when the U-boats started to use 4-rotor Enigma machines in February 1942 it took TEN MONTHS to break the code. The decoded messages were in German in blocks of five letters. They had to be carefully translated into English. On the 9th of May, 1941, U-110 had been about to attack an Allied convoy when it was forced to surface by British ships protecting the convoy. The German crew surrendered. The photographs below shows the boarding party from the destroyer HMS Bulldog, rowing out to the half-submerged U-boat. (U-110 later sank while being towed to a British naval base in Iceland).

The British sailors climbed into the conning tower and began a search of the deserted submarine. The bookshelves still contained books of every description - navigation manuals, seamanship manuals, code books and signal books. The Bulldog's telegraphist pointed to an interesting piece of equipment that looked like a typewriter. This, along with all the books from the shelves, was transferred with utmost care to HMS Bulldog. It was important that everything was kept dry as the code books and signal books were printed in ink that disappeared if they were dropped in seawater. On Bulldog's arrival back in Britain they were met by a representative from Bletchley Park, who photographed every page of every book. The 'interesting piece of equipment' turned out to be an Enigma machine, and the books contained the Enigma codes being used by the German navy. The British were anxious to make sure that the Germans did not find out that U-110 and its codebooks had been captured. All the sailors who took part in the operation were sworn to secrecy. If the Germans had found out, they would almost certainly have changed their codes. This would have made the code-breakers' job far more difficult - but by 1943 they had the help of Colossus (which NEVER decoded intercepts off enigma by the way) - the world's first programmable electronic digital computer. This British Naval message shown below dated 10th May reads: "a) Capture of U Boat 110 is to be referred to as Operation Primrose. b) Operation Primrose is to be treated with greatest secrecy and few people allowed to know as possible..."

Colossus** was built for the code-breakers at Bletchley Park by post office engineers in 1943 and was operational before D Day.The computer was as big as a room - 5 metres long, 3 metres deep and 2.5 metres high - and was made mainly from parts used for post office telephone and telegraph systems. Colossus worked by 'reading', through a photoelectric system, a teleprinter tape containing the letters of the coded message. It read 5,000 letters a second. All possible combinations of the coded message were checked with the cypher key generated by Colossus. A teleprinter typed out the results of Colossus's search, revealing the settings which had been used by the Germans to send their messages.

Ten Colossus Mark 2s were eventually built. They cracked the Lorenz & Siemens machine codes, which were based on a superior technology to that used in the enigma machines, and even more complicated ones devised by the Germans on their 12 - rotor cipher machines, giving a combination of 10 million, milllon. A complete Mark 2 Colossus machine has recently been rebuilt and is on display at Bletchley Park.** See note below The information revealed by the code-breakers at Bletchley Park was called ULTRA. ULTRA was so secret that only those who needed to know about it - like the British Prime Minister, Winston Churchill, or Roosevelt - were told of its existence.

For many years after the war, the work of the code-breakers remained a secret. The ULTRA files were locked away. Today more is known about Enigma and ULTRA. Historians can study the effects they had on the course of the war. Code breaking did not totally win the war, but it helped to shorten it - perhaps by a year or more. It also contributed to the success of many Allied campaigns from 1941 onwards. IBM later claimed to have invented the worlds first computer - WRONG!! Designed in the 30s, Colossus was up and running in the 40s!

North Africa, 1942 - By breaking codes used by Rommel's forces, the Allies could attack his supply routes, helping to
ensure Montgomery's victory in the Western Desert.

Battle of the Atlantic, 1940 - 1944 - Until convoys were better protected by escort ships and aircraft, one of the only
ways of fighting the U-boat threat was to use ULTRA to divert ships away from danger. This led Doenitz to suspect
that codes were being read, but his suspicions fell on deaf ears, enigma was unbreakable they said.

D-Day, 1944 - ULTRA revealed the size and location of German forces in Normandy before the Allied landings began.

At other times ULTRA was not used effectively. It did not prevent the Allied setbacks at Arnhem and the Ardennes in north-west Europe during the last year of the war. To prevent the Germans from suspecting that their codes were being broken, the Allies sometimes took no action even when they knew their enemy's plans.

The code-breaking methods used in the Second World War seem very old-fashioned to us. But the work at Bletchley Park led directly to the development of the computers we use today. The computing power of the room-sized Colossus can now be put into a Pentium microprocessor no bigger than your thumb. Modern computers can create incredibly complicated codes. These can only be broken by other computers thousands of times more powerful than Colossus. The codes which protect the security of vast networks such as banking systems and the Internet were thought to be unbreakable. But computer hackers have already found their way into these systems.

The Enigma machine, first patented in 1919, was after various improvements adopted by the German Navy in 1926, the Army in 1928, and the Air Force in 1935. It was also used by the Abwehr, the Sicherheitsdienst, the railways, and other government departments. From then until 1939, and indeed throughout the war, successive refinements were introduced, varying from service to service, and there were detailed changes in operating procedure until 1945. The following short description can therefore summarize only its main features and mention only a few of the Enigma variations.

The Enigma (see diagram below) was used solely to encipher and decipher messages. In its standard form it could not type a message out, let alone transmit or receive it. From the cipher operator's point of view, it consisted of first a keyboard of 26 letters in the pattern of the normal German typewriter:

     Q  W  E  R  T  Z  U  I  O
       A  S  D  F  G  H  J  K
     P  Y  X  C  V  B  N  M  L

with no keys for numerals or punctuation. Behind this keyboard was a "lampboard" of 26 small circular windows, each bearing a letter in the same QWERTZU pattern, which could light up, one at a time, from bulbs underneath. (The model with an A-Z keyboard, shown in several books on the Enigma, is a Polish-French replica, not an actual Enigma machine.) It measured about 13.5" x 11" x 6", and weighed about 26 lbs.

Behind the lampboard is the scrambler unit, consisting of a fixed wheel at each end, and a central space for three rotating wheels. The wheel to the right of this space is the fixed entry or plate (Eintrittwalze) carrying 26 contacts round its left side, ultimately connected to the keys of the keyboard in ordinary alphabetical order. To the left of the space is the reversing wheel (Umkehrwalze), which scrambles the current it receives and sends it back by a different route from that by which it came. This wheel too has a circle of 26 contacts.

The three central wheels were selected from a box of five. Monthly orders specified a new choice every day, as well as their relative order in the machine, e.g., V-I-III or II-IV-I, etc. Each of these rotating wheels has a circle of 26 spring-loaded terminals on its right side and 26 flat circular terminals on its left, so as to provide an ever-changing series of connections as it revolves. Each contains a different internal wiring and carries the letters A-Z or the numbers 01-26 round its inner ring, which can be turned and locked in any setting before the wheels specified for a given day are inserted into the machine in the prescribed order, though they can still be turned bodily through slits in the inner lid, and the letters A-Z can be read one at a time in the window beside each slit. The specified setting of ring against wheel was called the Ringstellung. Each time a letter key is pressed, the right wheel moves on one of its 26 places. Once during every 26 moves, at the "turnover position" on the right wheel, the middle wheel will also move on one place; and when the middle wheel reaches its own turnover position it moves on again when the next letter is keyed, together with the left wheel.

Finally, the vertical front of the Enigmas used by the Armed Services contained a "plugboard" (above) with 26 pairs of sockets, again in the QWERTZU pattern. These could be connected by twin-cable leads -- for example, coupling C to P, M to Z, J to S, and so on; but some sockets, usually six, were left unconnected. They were said to be "self-steckered." Stecker is a plug; Steckerbrett (usually called "steckerboard" at Bletchley) is a plugboard. Each time the cipher clerk keyed a letter, the right wheel moved on mechanically one place and, as explained above, from time to time the center and left wheels also moved. As each new letter (e.g., P) was keyed, the current, normally provided by an internal 4.5 volt battery -- although an outside power source could be used -- flowed from a terminal under that key to a socket (e.g., P) on the plugboard. From there it travelled via a lead to another socket (e.g., L), or, if the first socket was self-steckered, it stayed as P. Either way, it ran to the entry wheel, which did not alter it, through the pairs of terminals on all central wheels -- each of which normally altered it again -- to the Umkehrwalze or reversing wheel (with another alteration) and back through different circuits in all three wheels (hence still further alterations), out unaltered through the entry wheel, and back to the plugboard. Here its course again depended on whether that socket was self-steckered or cross-steckered; either way, it finally reached the lampboard and lit a bulb (e.g., W). Although the process, involving up to nine changes on the standard three-wheel machine, has taken some time to describe, it naturally took place virtually instantaneously. And it must be remembered that the moving on of at least one wheel, for every new letter keyed, introduced a new set of circuits for each new letter. It is important to note that, if you press any key (e.g., B), any other letter may light up (e.g., T); but if you continue to key letter B, the lampboard may give, say, P, F, O, J, C..., but never B. The sequence will repeat only after 16,900 (26 x 25 x 26) keyings, when the inner mechanism returns to the same position. Messages were limited to a maximum of 250 letters to avoid this recurrence, which might have otherwise helped us.

In choosing a basic set-up for the machine, there was a choice from the 60 possible wheel orders, the 17,576 ring-settings for each wheel order, and over 150 million million stecker-pairings (allowing for six self-steckered letters). So the total number of daily possible keys was about 159 million million million. In each of these configurations, the machine had a period of 16,900 (26 x 25 x 26) keyings before the mechanism returned to its original position. But there were weak points. The Enigma is simply a swapping machine of an advanced type. All Enigmas of the same model, set up in the same way, will produce identical swaps. In any position where keying B gives T, keying T will give B. And keying B can never give B. Although it was possible for one cipher clerk to carry out all the tasks of the enciphering procedure himself, this would have been a lengthy and confusing process; normally it called for a team of two. The cipher clerk would look at his signal text, which might begin Panzer ("tank(s)"). Typing P might give M on the lampboard; his Number Two would read this and write it down -- and so on through the message. The radio operator would then transmit the resulting enciphered signal. But first the machine had to be properly set up. Every month the operating instructions specified daily or more frequent changes to several variables. A typical daily "key" gave the clerk instructions for the first three steps of the enciphering procedure.

The wheel order (Walzenlage): the choice and position of the three wheels to be used (e.g. I-V-III).

The ring-setting (Ringstellung) of the left, middle, and right wheels (e.g. 06-20-24 denoting FTX).

The cross-plugging or "steckering" (Steckerverbindungen) (e.g. UA PF etc.).

The cipher clerk would set up his machine accordingly. Until the end of April 1940, he then continued as follows:

He turned his three wheels to a position chosen at random, the "indicator-setting" (e.g. JCM).

He twice keyed his own randomly selected choice of text-setting, or "message-setting" (e.g. BGZBGZ).

This came out as the "indicator" (e.g. TNUFDQ).

He set his wheels at BGZ and keyed the clear text of the message, thus obtaining the enciphered text, letter by letter.

The message as transmitted included four elements, as follows:

The preamble, transmitted in clear before the message itself, showing call-sign, time of origin, and number of letters in the text; this was followed by his chosen indicator setting (e.g., JCM).

A five-letter group comprising two padding letters (Füllbuchstaben) followed by the three-letter "discriminant" (Kenngruppe), e.g., JEU, which distinguished various types of Enigma traffic and showed which of many "keys" (sets of operator instructions) were being used. The latter were known at Bletchley by cover-names such as Kestrel, Light Blue, etc.

The six letters of the "indicator" TNUFDQ (No. 6 above).

The enciphered text of the signal, in five-letter groups

Once the signal had been transmitted in this form, and the text handed to the receiving cipher clerk -- whose wheels would already comply with the same daily instructions Nos. 1-3 -- he would duly move his wheels to JCM (No. 4 above), key TNUFDQ (No. 6), and read the reciprocally enciphered result BGZBGZ (No. 5.) He then turned his wheels to BGZ and deciphered the text by keying it out, with his Number Two noting each letter in turn. After 1 May 1940 this procedure was changed. Presumably the German cryptographic authorities had belatedly recognized that the double encipherment of the text-setting represented a security risk which far outweighed the advantage of the double-check it provided. From that date the random choice of text-setting (e.g., BGZ as in No. 5) was keyed only once, giving TNU instead of TNUFDQ.

Bear in mind that the foregoing description of mechanism and procedure applies only to the standard Enigma used by the German Army and Air Force. The Navy provided three special wheels in addition to the five Army-Air Force wheels, and thus had a set of eight to choose from. On 1 February 1942 they added an extra settable wheel, next to the Umkehrwalze, resulting in the M4 model, often called the "4-wheel" Enigma. The railways, police, and post office used older Enigma models, while the Abwehr used an advanced but unsteckered one, and a different enciphering procedure, with a Grundstellung specified for each day's settings, instead of allowing a random choice. Certain other unusual models had a 28-letter keyboard and wheel system. It seems clear that the "29-contact rotor" (wheel) suggested for this machine could not have existed (see C. A. Deavours and L. Kruh, Machine Cryptography and Modern Cryptanalysis. Norwood, Mass.: Artech House, 1985, 96-7.) The Enigma was essentially a reversing machine with an even number of wheel contacts, and although Ä and Ü have been added, there is no Ö. The 29-letter keyboard of this machine is thought to have had one letter, X, which bypassed the wheels and always gave the letter X.

Enigma being used on board a U Boat

Hugh Sebag-Montefiore's book "Enigma - the Battle for the Code" is published by Weidenfeld & Nicholson at £20.

An enigma machine was also found on the U Boat 534, which was raised and has its own page here.


Here I would like to mention Bill Tutte. He was handed intercepts by frustrated code breakers taken from a machine that could generate 1.6 billion difference combinations and employed 12 wheels with 41 settings on each wheel, and based on teleprinter code and binary. With a pencil and rectangular sheets of paper he realised that the magic number was 41, the prime number of 574. In November 1942 he successfully cracked the Lorenze Machine. One of the early successes of Bill was he learnt of the impending major push against the Red Army near a place called Kursk. Not only times, but dispositions and directions of attack. England was able to warn Russia of this but via an indirect route as Stalin was not on the Ultra information list, and they were ready when Germany attacked.  Kursk went down as the biggest tank battle in history and also the biggest aerial battle. I also mention a man, a GPO engineer called Fellows, who not long after this invented the worlds first computer. BUT, Russia had a british traitor in Bletchley Park who picked up the raw decrypts in Hut 6, the luftwaffe hit. Stalin launched a pre-emptive strike on the Luftwaffe bases in Russia and suffered heavy losses.

Regarding Collossus, the first programmable computer. After the war Churchill said that Collossus had been dismantled. But 2 survived and were installed in GCHQ and were used into the 1960s. In 1946 the Americans claimed to have invented the computer. The fact they we already had TWO in operation seems to have escaped their attention. Mind you, they were Ultra Secret until many years after the war. Alan Turing wrote a paper in the mid 30s on computers and Tommy Fellows is the name of the man who invented the computer. Read and weep Americans!!!

Bletchley Park, remarkably, never saw a Lorenz machine until after the war. All was done by hand and by the 'tunny machine'. Tunny was the name given to the decrypts from Colossus. Bill Tutte must never be forgotten for his monumental expertise and achievements. Bill Fellows was decorated by the Canadians for his work, but has never been recognised here in the UK, a very dismal state of affairs. In June 1993 he went to a local college to learn how to use a computer and was awarded a certificate!! Tommy died in 1998.

Tunny electric typewriter

As the number of intercepts, now being made at Knockholt in Kent, increased a section was formed in Bletchley Park headed by Major Ralph Tester and known as the Testery. To understand Lorenz the team needed something known as depths, when 2 or more messages were intercepted using the same key at source. This was realised when a tired operator in Greece was asked to re-transmit a large message as part of it had not been received. He did this, but failed the change the key. This was what we had been waiting for. The unknown German operator also abbreviated some words in the second transmission, giving a small but obvious change in the 'order'.

After nearly 4,000 characters had been keyed in at the sending end, by hand, the operator at the receiving end sent back by radio the equivalent, in German, of "didn't get that — send it again".

They now both put their Lorenz machines back to the same start position. Absolutely forbidden, but they did it. The operator at the sending end then began to key in the message again, by hand. If he had been an automaton and used exactly the same key strokes as the first time then all the interceptors would have got would have been two identical copies of the cipher text. Input the same — machines generating the same obscuring characters — same cipher text. But being only human and being thoroughly disgusted at having to key it all again, the sending operator began to make differences in the second message compared to the first.

The message began with that well known German phrase SPRUCHNUMMER — "message number" in English. The first time the operator keyed in S P R U C H N U M M E R. The second time he keyed in S P R U C H N R and then the rest of the message text. Now NR means the same as NUMMER, so what difference did that make? It meant that immediately following the N the two texts were different. But the machines were generating the same obscuring sequence, therefore the cipher texts were different from that point on.

The interceptors at Knockholt realised the possible importance of these two messages because the twelve letter indicators were the same. They were sent post-haste to John Tiltman at Bletchley Park. Tiltman applied the same additive technique to this pair as he had to previous Depths. But this time he was able to get much further with working out the actual message texts because when he tried SPRUCHNUMMER at the start he immediately spotted that the second message was nearly identical to the first. Thus the combined errors of having the machines back to the same start position and the text being re-keyed with just slight differences enabled Tiltman to recover completely both texts. The second one was about 500 characters shorter than the first where the German operator had been saving his fingers. This fact also allowed Tiltman to assign the correct message to its original cipher text.

Now Tiltman could add together, character by character, the corresponding cipher and message texts revealing for the first time a long stretch of the obscuring character sequence being generated by this German cipher machine. He did not know how the machine did it, but he knew that this was what it was generating! This is but a minute sprinkle of information. For a more detailed study please visit the excellent site linked below.


Footnotes & Describing a Visit

A Description of a Visit to Bletchley Park

With the publicity given to Bletchley Park through television programmes, the new film and the theft of one of its Enigma machines, there was no lack of interest on a coach outing amongst us from the Chelmer and Blackwater Committee of King George’s Fund for Sailors. Bletchley Park Mansion Some of them were ex-Wrens, others ex-naval personnel and one lady who actually worked at Station X during the war, We were shown the various huts dotted around the 55 acres of ground surrounding the Bletchley Park’s Victorian mansion that MI6 first took over in 1938. In these huts the de-coding took place, with no one group knowing what the others were doing. During the war, Bletchley Park became more and more active, ending up with 12,000 people working there - all in the greatest secrecy keep track of enemy activities. maintained for many years afterwards. German messages, picked up at various Y radio stations around the country and overseas, were rushed to Bletchley - Park to be de-coded, sometimes at dead of night. With some help from German code tables captured from German weather ships and from the submarine U-110 in 1941, Bletchley Park was able to keep track of enemy activities.

Those of us who had our convoys diverted or re-routed during the Battle of the Atlantic had no idea why. We naturally suspected that through intelligence U-boat positions had been obtained and our courses had been changed accordingly. But we had no idea how the Enigma machine and decoding of German U-boat messages by Bletchley Park achieved this. Situated mid-way between Oxford and Cambridge, it was able to draw on the best brains available from these universities to find ways of de-coding German messages. Alan Turing, a young Cambridge professor, was reputed to be a genius, if a little eccentric, as were some of the other brilliant minds that worked there. The task of decoding was very exacting and was carried out by people who included professors, mathematicians and crossword addicts. Hitler had such confidence in the Enigma machine that he was quite confident we would not be able to crack the codes it produced. Another machine we saw was a reproduction of the great Colossus used towards the end of war, which was the first world’s computer. It worked at fantastic speeds to decode secret German messages. Our guide took us to the stable yard where homing pigeons were housed in aloft. They would be occasionally dropped over enemy occupied territory, to be picked up by members of the Resistance, who would attach messages to them and release them to return to Bletchley Park. In this way Germans could not pick up radio messages. There’s a tennis court at Bletchley Park constructed at the instigation of Winston Churchill who thought it necessary the people should have some form of recreation.

But it was not all pleasure for the staff at Bletchley. In order to get the German messages decoded quickly it was necessary for them to work in continuous shifts. Early in the war they found the Luftwaffe codes relatively easy to break. The naval ones were more difficult. But, in May, 1941, they de-coded a message confirming the Bismarck was making for Brest as the Royal Navy desperately searched for her. “Sink the Bismarck,” Churchill boomed. They did, but only because Bletchley told them where she was heading for. Our tour was completed by a visit to the Faulkner Museum where uniforms, model aircraft and aero engine parts - amongst other artefacts - were displayed. Finally we were taken through the cryptology trail which showed re-constructed de-coding rooms and H Block where the Colossus machine has been re-built. We were also invited to operate an Enigma machine on which we were able to press the letter keys that illuminated a different letter to each key pressed, thereby producing a code. Our successful visit provided a real insight into what went on behind the scenes in the last war. Bletchley Park, now run by a trust formed at the instigation of some of those who worked there, is a monument to their great efforts that shortened the war by at least two years.

By 1946. every scrap of evidence of code-breaking had been removed from Station X. Bletchley Park Trust was formed to preserve the site for the nation Bletchley Park is open every weekend from 10-3Oam to 5pm with last admission at 3.3Opm. Admission is £5 (adults) and £4 for concessions. There is free parking and Bletchley railway station is a 200 yard walk along a sign posted footpath. For further information, visit their website at Prices and times as at Nov 2001.

From a Ministry of Defence News Item 6 July 2005: The code-breaker who revolutionised British reading of the Enigma code, Marian Rejewski, was honoured by Chief of the Defence Staff, General Sir Michael Walker, and his Polish counterpart, General Czeslaw Piatas at a ceremony on 4 July 2005. Rejewski's work has been described "the mathematical theorem that won World War II".  Rejewski returned to Poland at the end of hostilities and died in 1980.  As a result of the Cold War, he never received his 1939 - 45 War Medal and his story has gone largely untold. Marian's daughter, Mrs Janina Sylwestrzak, received her father's War Medal on his behalf in the ceremony at Lancaster House. Marian's work on Enigma's "Ultra" code started in Poland in 1932 and included clandestine meetings with British intelligence staff in the Kabaty Woods South of Warsaw, immediately prior to the outbreak of war.  His work continued in Vichy France during 1942 before he fled France and was imprisoned in Spain. He finally escaped through Gibraltar in an old Dakota aircraft and arrived in Britain to continue his work at Bletchley Park in 1943.  Chief of the Defence Staff, General Walker said: "The work of Marian Rejewski, and his colleagues at Bletchley Park, substantially altered the course of the war.  His story and the obstacles he had to overcome to make his vital contribution are truly remarkable and it is a privilege to honour him with this medal today."

Biography and History

Marian Rejewski was born on 16 August 1905 in Bydgoszcz, Poland. He was a mathematics graduate of Poznan University who, as a student, had attended a cryptology course organized by the Polish General Staff's Cipher Bureau. He joined the Biuro Szyfrow (Cipher Bureau) of Polish Military Intelligence in September 1932.  There he studied ways of cracking the German Army's Enigma cipher machine, which had come into service in 1930. His achievements jump-started British reading of Enigma in World War II ("Ultra"), and the intelligence so gained may have substantially altered the course of the war.

Rejewski fundamentally advanced cryptanalysis by applying pure mathematics - permutation theory - to break the Enigma cipher for the first time. Previous methods had exploited patterns and statistics in natural language texts such as letter-frequency analysis.  Rejewski's mathematical techniques, combined with material supplied by French military intelligence, enabled him to develop methods of breaking the periodic as well as individual keys used in encrypting messages on the Enigma machine.

Rejewski devised a mathematical theorem that wartime Bletchley Park luminary, Professor I J Good, has described as "the mathematical theorem that won World War II." Details of the Polish achievements were revealed to British and French intelligence representatives in a meeting at a secret Polish Cipher Bureau facility at Pyry, in the Kabaty Woods south of Warsaw, on 25 July 1939. The Germans had made changes to Enigma equipment and procedures in 1938 and 1939 that increased the difficulty of breaking messages; and as it became clear that war was imminent and Polish resources would not suffice to optimally keep pace with the evolution of Enigma encryption, the Polish General Staff and government had decided to bring their western allies into the secret.

With the crucial Polish contribution of reconstructed sight-unseen German Enigma machines and the Poles' cryptological techniques and equipment, the British at Bletchley Park, and later the Americans, were able to continue the work of breaking German Army, Air Force, Nazi Party SD, and (though with substantially greater difficulty) Naval Enigma traffic. In September 1939, after the outbreak of World War II, Rejewski and his fellow Cipher Bureau workers were evacuated from Poland via Romania to France.  At "PC Bruno," outside Paris, they continued their work at breaking Enigma ciphers, collaborating by teletype with their opposite numbers at Bletchley Park. When "Bruno" was evacuated upon Germany's invasion of France, the Polish cryptologists and their ancillary staff worked for two years in unoccupied southern (Vichy) France and outside of Algiers in French North Africa. Following the German takeover of the "Free Zone" in November 1942, the secret French-Polish "Cadix" centre in southern France was evacuated.  Its Polish military chiefs were captured and imprisoned by the Germans but protected the secret of Enigma decryption. Rozycki, the youngest of the three mathematicians, had died in the January 1942 sinking of a French passenger ship as he was returning from a stint in Algeria to "Cadix" in southern France. Rejewski and Zygalski fled France for Spain, where they were arrested and imprisoned for three months.  Released upon the intervention of the Polish Red Cross, almost three months later, in July 1943, they made it to Portugal; from there, aboard the HMS Scottish, to Gibraltar; and thence, aboard an old Dakota, to Britain.

Here Rejewski and Zygalski were inducted as privates into the Polish Army (they would eventually be promoted to lieutenant) and employed at cracking German SS and SD hand ciphers. After the war, Zygalski remained in Britain while Rejewski took a big risk and returned to Poland to reunite with his wife and two children.  He worked as a bookkeeper at a factory-bringing disfavor on himself when he discovered irregularities-until his retirement, and was silent about his work before and during the war until, in the 1970's, he contacted the military historian Wladyslaw Kozaczuk. He published a number of papers on his cryptological work and contributed generously to books on the subject. Rejewski died on 13 February 1980 in Warsaw and was buried at the Powazki Cemetery, one of Poland's pantheons of the great and valiant.

The Polish Mathematical Society has honoured him with a special medal. An odd footnote to the story of Rejewski's cryptologic contributions is that his role in World War II had been so obscure that one best-selling book (William Stevenson's A Man Called Intrepid, 1976) not only did not credit him with the work he had done but identified him as "Mademoiselle Marian Rewjeski."

Footnote on Ken Lacroix: In June 2007 I received an email from a gent, Geoffrey Ellis, in which he casts doubt on the award that Ken received, claiming he only received a Mention in Despatches and, consequently, would not have made a trip to the Palace. He mentions: I hold to question the suggestion of an award of a medal to Ken Lacroix as he was only "Mentioned in Despatches". In which case it is unlikely that he would have been presented to the king in my opinion. My information comes from the Supplement to the London Gazette in which all awards are registered - and if it doesn't appear here, it didn't happen. Geoff is of course quite right about the London Gazette. He goes on: (Gazette Edition, Issue 36169, 10-September-1943), in the LH column there appears a section headed "For leadership and devotion to duty in action with enemy submarines in the Mediterranean, while serving in HM Ships Packenham, Petard, Hero, Dulverton & Hurworth". There the follows a list of DSO awards, DSC awards, DSM awards, and finally "Mention in Despatches". This listing flows over into the RH column where you will find Able Seaman Kenneth Vivian Lacroix, P/SDX1471 mentioned. From this it is unclear what part he played in the recovery of the Enigma documents and whilst his contribution to the exercise was not insignificant, it is certain that he was not awarded anything other than a 'mention in despatches'. In a second email Geoff tells me that: In the doorway of the Newhaven Local & Maritime Museum I just happened to see a photocopy of a newspaper that credited Ken Lacroix (a local man, no longer with us) with the glory of having rescued the Enigma Code books from the sinking submarine and being awarded the DSM. I was unaware of this thought it would make an interesting point to include in the presentation. However, the award of a DSM seemed to me to be pretty small beer for such an action so I decided to investigate further. The Newhaven Historical Society Secretary was quite bemused that I should challenge this report and told me "For an authoritative account of the incident read "Seizing the Enigma" by David Khan, Chapter 18 The George Cross. For my money our version stays". I don't have this book so I cannot read it. For my part I would be delighted to think that a local man was key to this piece of history, but when the true credit for this action has been registered in the London Gazette, and Tamworth Town has dedicated a special monument to these heroes (which would not have been done with considerable research) see, it would be less than honourable to propagate the claim that the glory for retrieving the Code books belongs to Ken Lacroix. Many medals were awarded according to the London Gazette, and a dozen or so MIDs of which Ken Lacroix was one.

Thanks to extensive research from Geoffrey Ellis the mystery has been solved. Ken was awarded the Mention in Despatches for the enigma incident BUT was awarded the DSM for another action involving a submarine later in the war. The fact that the London Gazette spelt his name wrong, La Croix, caused the confusion in the first place. Geoff tells me: " Further to the apparent non-appearance of entries in the London Gazette for Lacroix, the conundrum has now been solved. His is twice credited (once for MID, and once for his DSM) in LG's for 31/3/44 and 28/4/44 under the name of "La Croix". What a difference a space makes!" What has arisen from this investigation is that Lacroix was awarded his DSM for his part in destroying a U-boat on 12 February 1944 when Petard was escorting a convoy close to the Maldives Islands and the convoy was attacked by a Japanese submarine; many months and thousands of miles apart from the alleged incident. Lacroix got a second Mention in Dispatches on 04 April 1944 for actions in the Aegean also whilst on board HMS Petard. Now, the conversation may well have took place with HM THE King but it would have been in 1944.

Visit Geoffrey's site, its amazing!!!

Ken's London Gazette entry:  I had a link here but it appears to have vanished into a black hole.


Geoff sent me some references, of which I have not yet, at the time of typing, had a chance to cross examine:

Other websites referring are... and and and

Navy News...

The MOD...

Family (Tommy Brown's sister) account on the BBC WW2 archive...

March 2005: I got this email from a gent in Belgium called Dirk Rijmenants.

I have done a lot of research on Enigma and since I could not find a really realistic simulation of the Enigma, I decided to write my own simulation, since I'm also a programmer. After lots of research and with the kind help of people like Frode Weierud of CSG and Tom Perera from the Enigma museum, I created a true simulation, identical in view and handling. The Graphic User Interface is unique!

You can actually open the cover, change the rotors and ring settings, insert plugs etc etc. The machine is fully compatible with the real Wehrmacht Enigma and the Kriegsmarine M4, and the graphics and Enigma parts are very realistic and identical to the real pieces! It comes with a help file with a manual, all tech details and history of Enigma. Since I always wanted to share my Crypto passion with other, I decide to make the program available for free to anyone who's interested. So it's freeware (no commercial use allowed).

Try it for yourself, its a really very good program- mk

Did Turing Commit Suicide or Was it an Accident?

This is copied from a forum which in turn was copied from elsewhere.

Alan Turing, the British mathematical genius and codebreaker born 100 years ago on 23 June, may not have committed suicide, as is widely believed.

In a conference in Oxford on Saturday, Turing expert Prof Jack Copeland will question the evidence that was presented at the 1954 inquest.

He believes the evidence would not today be accepted as sufficient to establish a suicide verdict. Indeed, he argues, Turing's death may equally probably have been an accident. What is well known and accepted is that Alan Turing died of cyanide poisoning.  His housekeeper famously found the 41-year-old mathematician dead in his bed, with a half-eaten apple on his bedside table.

It is widely said that Turing had been haunted by the story of the poisoned apple in the fairy tale of Snow White and the Seven Dwarfs, and had resorted to the same desperate measure to end the persecution he was suffering as a result of his homosexuality.

But according to Prof Copeland, it was Turing's habit to take an apple at bedtime, and that it was quite usual for him not to finish it; the half-eaten remains found near his body cannot be seen as an indication of a deliberate act.  Indeed, the police never tested the apple for the presence of cyanide.

Moreover, Prof Copeland emphasises, a coroner these days would demand evidence of pre-meditation before announcing a verdict of suicide, yet nothing in the accounts of Turing's last days suggest he was in anything but a cheerful mood. He had left a note on his office desk, as was his practice, the previous Friday to remind himself of the tasks to be done on his return after the Bank Holiday weekend.

Nevertheless, at the inquest, the coroner, Mr JAK Ferns declared: "In a man of his type, one never knows what his mental processes are going to do next." What he meant by "of this type" is unclear. The motive for suicide is easy to imagine. In 1952, after he had reported a petty burglary, Turing found himself being investigated for "acts of gross indecency" after he revealed he had had a male lover in his house.

Faced with the prospect of imprisonment, and perhaps with it the loss of the mathematics post he held at Manchester University, which gave him access to one of the world's only computers, Turing accepted the alternative of "chemical castration" - hormone treatment that was supposed to suppress his sexual urges. It is often repeated that the chemicals caused him to grow breasts, though Turing is only known to have mentioned this once.

The authorities' continuing interest in Turing became apparent in 1953 when a gay Norwegian acquaintance, Kjell, announced by postcard his intention to visit him at his Wilmslow home, but mysteriously never arrived. Turing told a friend, by way of explanation: "At one stage, the police over the north of England were out searching for him."

With six decades of hindsight, these oppressive attentions, the nation's failure to appreciate his wartime contributions, his apparent sidelining at the Manchester computer department, have led to a tragic picture of Turing being hounded during his last years, and suicide being a natural outcome.

But Prof Copeland argues that on the contrary, Turing's career was at an intellectual high, and that he had borne his treatment "with good humour".

Of the Kjell affair, Turing had written that "for sheer incident, it rivalled the Arnold [gross-indecency] story"; and immediately after his conviction had told a friend: "The day of the trial was by no means disagreeable. "Whilst in custody with the other criminals, I had a very agreeable sense of irresponsibility, rather like being back at school." On the face of it, these are not the expressions of someone ground down by adversity.

What is more, Turing had tolerated the year-long hormone treatment and the terms of his probation ("my shining virtue was terrific") with amused fortitude, and another year had since passed seemingly without incident. In statements to the coroner, friends had attested to his good humour in the days before his death.  His neighbour described him throwing "such a jolly [tea] party" for her and her son four days before he died.  His close friend Robin Gandy, who had stayed with him the weekend before, said that Turing "seemed, if anything, happier than usual".

Yet the coroner recorded a verdict of suicide "while the balance of his mind was disturbed". Prof Copeland believes the alternative explanation made at the time by Turing's mother is equally likely. Turing had cyanide in his house for chemical experiments he conducted in his tiny spare room - the nightmare room he had dubbed it.

He had been electrolysing solutions of the poison, and electroplating spoons with gold, a process that requires potassium cyanide. Although famed for his cerebral powers, Turing had also always shown an experimental bent, and these activities were not unusual for him.

But Turing was careless, Prof Copeland argues. The electrolysis experiment was wired into the ceiling light socket.  On another occasion, an experiment had resulted in severe electric shocks.  And he was known for tasting chemicals to identify them.  Perhaps he had accidentally put his apple into a puddle of cyanide. Or perhaps, more likely, he had accidentally inhaled cyanide vapours from the bubbling liquid.

Prof Copeland notes that the nightmare room had a "strong smell" of cyanide after Turing's death; that inhalation leads to a slower death than ingestion; and that the distribution of the poison in Turing's organs was more consistent with inhalation than with ingestion.

In his authoritative biography, Andrew Hodges suggests that the experiment was a ruse to disguise suicide, a scenario Turing had apparently mentioned to a friend in the past. But Jack Copeland argues the evidence should be taken at face value - that an accidental death is certainly consistent with all the currently known circumstances.  The problem, he complains, is that the investigation was conducted so poorly that even murder cannot be ruled out. An "open verdict", recognising this degree of ignorance, would be his preferred position.  None of this excuses the treatment of Turing during his final years, says Prof Copeland.  "Turing was hounded," he told the BBC, adding: "Yet he remained cheerful and humorous. The thing is to tell the truth in so far as we know it, and not to speculate.  In a way we have in modern times been recreating the narrative of Turing's life, and we have recreated him as an unhappy young man who committed suicide. But the evidence is not there.  The exact circumstances of Turing's death will probably always be unclear," Prof Copeland concludes. "Perhaps we should just shrug our shoulders, and focus on Turing's life and extraordinary work."

In a third email Geoff tells me:  I made a point of visiting the Newhaven Local & Maritime Museum this morning to find out more about the offending newspaper article. The photocopy appears to be of a full centrefold article of The Mirror dated Monday, 12 June 2000 and contains an (approx:) A5-size picture of Ken Lacroix proudly brandishing 9 or more medals he won for outstanding bravery, including helping to retrieve vital codebooks from a German U-boat, with the heading "Seizing the Enigma: Sole survivor tells of U-Boat raid". (See attachments).  I apologise for the quality of the images but my camera was confused by the encapsulation and the less than perfect resolution of the photocopy itself. These are the best of about twenty images, none of which are satisfactory. I may have to return to the museum with my mp3 recorder, dictate the text and transcribe it manually if necessary. The article goes on to describe how he was on the conning tower... and relates the alleged conversation with the King. A typed appendix states "Ken Lacroix, a man of this town, Newhaven, was awarded the Distinguished Service Medal for his bravery in recovering the latest Enigma Codes from the sinking German 'U' Boat, U-559."  It then mentions a proposed trip to BP. I cannot imagine that this article went down with Tommy Brown's family, nor with the North Tyneside Veterans' Committee who in partnership with the North Tyneside Council have since named a room after Tommy Brown and commissioned a stained glass window at the Saville Exchange Building, North Shields, or indeed the local ex-service and civic organisations of Tamworth who later erected a monument to the three brave souls Grazier, Fasson and Brown for their heroic deeds. I await the results of Geoff's investigation with eagerness.
6. Irmgard Enge 'Enigma From The Other Side'
In the August 2016 episode of the Bletchley Park Podcast, Enigma from the other side tells the story of Irmgard Enge in 'Enigma From The Other Side'

Sharing her unique story as part of Bletchley Park’s Oral History Project, Irmgard Enge, later Copley, tells how she was part of a secret operation to make sure the Allies did not find out how badly German aeroplanes and munitions factories were being damaged by bombs. She also recalls friendly - and less friendly - French people living near the air base where she was posted.

Once the war had ended, Irmgard reluctantly agreed to go to a dance with her friend. She hadn’t wanted to go because there would be British soldiers there and she didn’t want to dance with the enemy. But her friend persuaded her and there she met her husband, an English soldier. See link below this.
**Note on Colossus. Email Sept 2010: I have today been to Bletchley Park where they held their codebreaker's reunion. Fascinating talking to them (mostly women over 86).  I took the opportunity to seek out Tony Sale who is the master mind behind the rebuild of The Colossus now working at B.P. I asked him the direct question, was The Colossus machine ever used in any way to break Enigma enciphered messages. The answer from him was definitely no, never. Colossus was only "geared" to decipher teleprinter type, high speed messages that were taken down on an attenuator on tapes to be put into Colossus. The messages as received were not in Morse as for Enigma. Operators seeking The German Lorenz teleprinter generated messages immediately they were identified had to switch on to the attenuator to record. Tony Sale is THE Colossus expert so our little problem is solved. Ken Hutchings. February 2012. I am grateful to Ralph Erskine for helping me out with a few bits of misinformation and subsequent changes. As I explained to Ralph, I do this as a hobby and rely on others to provide me with information, sometimes in books, sometimes directly via email.
February 2015: The only known examples of Banbury sheets, devised by Alan Turing to help break Enigma, were found stuffed into cracks between beams during the restoration of Codebreaking Hut 6. The sheets were found alongside notes and calculations, found folded and pushed into the roof, presumably to keep out drafts. Bletchley Park's Director of Learning and Collections, Victoria Worpole, said: "It's very exciting. We're unveiling a mystery." They will feature in an exhibition opening soon in Hut 12.  



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Although linked from this page, I have used material from only one or two these sites: my thanks to Darek for this link