The Secrets of Station X (10 page)

Meanwhile, Nigel de Grey was put in charge of an ‘Intelligence Exchange’ Section, Hut 3a, to work on long-term intelligence analysis and reporting. ‘There was an inevitable tendency for us to concentrate on the more urgent and spectacular aspects of our information,’ Lucas said, ‘to try to send out intentions and front lines, battle HQs and tactics with all possible speed, while ignoring by comparison matters of more lasting interest such as organisation, strength, habits of the
Luftwaffe
and the German Army and so on.’ De Grey’s role was to remedy that by setting up a group of backroom analysts and reporters. One of their first tasks was to set about acquiring more detailed maps than the Baedeker tourist guides the Hut 3 Watchkeepers had been forced to work with during the campaigns in Norway and France. They also looked at the various terms used by the Germans, many of which had completely baffled academics more used to translating Goethe than Guderian; and, most importantly of all, began to build up a detailed picture of the structure of the German armed forces.

The fall of France cast a dark shadow over everyone at Bletchley Park, but the French liaison officers from ‘Mission
Richard’ were clearly worst affected. ‘I remember seeing several of the Frenchmen who were attached to the French Mission here clustered around the wireless set with their ears almost glued to it,’ said Phoebe Senyard. ‘They were listening to very faint announcements made by the BBC, or getting on to a French station and becoming more and more dejected and downcast with every fresh announcement.’

Mavis Lever was eating her dinner in the mansion dining hall when the news that Paris had fallen was announced. ‘We had some Frenchmen working with us at the time and I was sitting next to one of them and he burst into tears,’ she said. ‘I simply did not know what to do. So, I went on eating my sausages. I mean we weren’t going to get any more and it seemed to me there was nothing really I could do if other people were going to burst into tears. I’d got a night shift to work on, so on with the sausages.’

Following the German invasion, Bertrand and the Poles set up a new station on a country estate, the Château de Fouzes at Uzès in Provence, working with the Vichy French government’s
Groupement des Controles Radioélectriques
. This was supposed to be monitoring British communications with the underground resistance movement but in fact assisted Bertrand and the Poles by intercepting Enigma traffic and allowing them to continue to do their work on Enigma. Bertrand also managed to make contact with Bletchley Park, via MI6. They remained there until the Germans occupied the whole of France in October 1942 when they escaped to the UK.

Hut 6 was at this stage still breaking Enigma keys by hand using the Cillies and Herivelismus and waiting for Turing’s Bombes to help them. The first of the Bombes, known with misplaced optimism as Victory, had been produced in the space of three months and had come on stream in March 1940. It was a fast running electrical machine in a bronze cabinet six-
and-a
-half feet high, more than seven feet wide and two-and-a-half feet deep, containing a series of thirty rotating drums equating
to the wheels of ten Enigma machines, although later versions simulated the action of twelve machines. It contained around ten miles of wire and about a million soldered connections.

The Bombe was a remarkable piece of technology for its time. It was designed to run through all the various possibilities – of wheel choice, order, ring position and machine settings – at high speed in order to test that the Cillies or cribs suspected by the codebreakers were actually in use. The codebreakers provided the operators with a ‘menu’ suggesting possible
equations
of clear letters to encyphered letters which was fed into the Bombe. Each time the machine found a possible match, it stopped and was quickly tested by the operator on a British Type-X cypher machine rigged up to work like an Enigma machine to see if it produced German text.

If it did, the operator was able to declare: ‘The job’s up’ and pass it back for decryption. If it was just garbled letters, as was frequently the case, the process continued until the Bombe had found the right combination or exhausted all the possibilities, in which case the codebreakers’ suspected crib or Cilli didn’t work and a new one had to be found. But Victory kept making ‘false stops’ and took far too long to test a single ‘menu’ so it was only used on Naval Enigma, which was not yet being broken on a regular basis. Welchman suggested a
solution
of a diagonal board to cure the ‘false stops’ and Turing immediately agreed this would correct the problem. It was not until August 1940 that the first of the Bombes with the diagonal board,
Agnus Dei
, later corrupted to Agnes or even Aggie, was introduced, assisting Hut 6 in its breaks into the Enigma cyphers.

With the end to fighting in France and Norway, the Germans turned their attention towards Britain. Concerns over the possibility of an imminent invasion pervaded the atmosphere at Bletchley Park. ‘The sinister covername for an
Operation Sea Lion
began to appear in the
Luftwaffe
traffic,’ said de Grey. ‘It did not require much ingenuity to identify this name with the
preparations for invasion which continued unabated
throughout
the late summer and early autumn.’

Neville Chamberlain’s association with appeasement and the inadequate response to the German attack on Norway had led, at the beginning of May, to his resignation and replacement by Winston Churchill, the man who had ordered Room 40 to be set up. The new Prime Minister soon became obsessed with Bletchley Park, treasuring the intercepts delivered to him each day by Stewart Menzies, the Chief of MI6 and Director of Bletchley Park, in a battered old wooden dispatch box covered in fading yellow leather.

With Hitler’s next move expected to be an attack on Britain itself, Churchill made a series of speeches aimed at building up ‘the bulldog spirit’. They were epitomised by his ‘finest hour’ address to the House of Commons and his warning that the British would defend their island on the beaches. Detachments of Home Guards were set up around the country and Bletchley was no exception. Some of the codebreakers were enthusiastic recruits. Malcolm Kennedy recorded in his diary that there had been a wireless appeal ‘for volunteers between seventeen and sixty-five to form local defence units against parachutists. I sent in my name to join the detachment which is to be formed at Bletchley, so I may yet have a chance to take a smack at Brother Boche once more!’

One of the more surprising members of the Bletchley Home Guard was Alan Turing. But in typically eccentric fashion he did it solely on his own terms, joining only in order to learn how to fire a rifle, said Peter Twinn. ‘They told him to fill this form in and Turing thought to himself: “I don’t see why I should sign this, it won’t do me any good and it might be a bit inconvenient.” So when he’d learned how to fire a rifle and done as much as he thought was of value to him, he thought: “Well, I’ve got everything I can out of this, I’ll just give up going to the Home Guard.” When the officer in charge said he would do what he was told because he had agreed to be subject to
military discipline, Turing replied, and I can hear him saying it: “Well, you had better look at my form. You’ll see I didn’t sign that bit”.’

Ann Harding, a colleague of both ‘Prof’ Turing and Peter Twinn in the German Naval Section Hut 4, recalled that the men taking part in the Home Guard were known as ‘parashots’ since they were expected to shoot the German paratroopers as they tried to land. ‘Most of the men had become parashots,’ Harding recalled. ‘One day Prof had an awful thought. “Peter, what do we do if they land in the maze? There would be the most awful muddle, Peter, with us and them getting lost.” This was quite a thought as it was a large maze. The threat of
invasion
was very real. Many people had heavy sticks or, in the case of farms, pitchforks hidden behind their doors, ready to attack.’

Noel Currer-Briggs, an Intelligence Corps officer, recalled that at one point a mixture of the Home Guard and the regular Army marched into Bletchley as part of an Army recruiting campaign. ‘There were lots of oddballs there, people from all over Europe with obscure languages, and there was one chap from Eastern Europe in battledress and a bowler hat, much to the dismay of the sergeant who was trying to make us look smart. It made Dad’s Army look like the Coldstream Guards.’

Plans were put in place to set up a mobile codebreaking unit to operate behind the defending British troops should the Germans manage to cross the Channel. The codebreakers’ records were to be evacuated to Canada and there was even talk of moving GC&CS across the Atlantic as well if need be.

‘The war situation was now becoming very grim,’ said Phoebe Senyard.

Column BQ, as the mobile unit was to be called, was to comprise around 500 people: 140 of the codebreakers and 360 wireless operators from the various Y stations. The transport was to be a mixture of private cars and four ancient Midland Red buses, hired by the War Office, one of which promptly split along the length of its roof while the other three
continuously
broke down. ‘I am told that the petrol consumption is about five miles to the gallon,’ complained one of the column’s organisers, ‘and I think it questionable if they had to go a long journey whether they would arrive at their destination with any degree of certainty.’

Most of the private vehicles were in somewhat better
condition
, although possibly no less dangerous. One of the cars volunteered as Column BQ transport was the grey Bentley driven by Diana Russell Clarke, who had become renowned for driving it at breakneck speed along the country roads around Bletchley. ‘There was one occasion when I was coming back from leave going about sixty-five which now we would think was very slow, and burst a front tyre,’ she said.

Fortunately, the invasion never came and neither the Bentley nor the buses were ever needed. The codebreakers were able to remain at Bletchley Park where it was not simply a question of breaking Enigma. Hitler and his generals realised that if they were to invade Britain they would need to control the skies otherwise the RAF and the Royal Navy would cause major, probably critical, damage to their forces as they tried to land. So on 10 July 1940, the
Luftwaffe
launched a series of attacks on coastal ports, and subsequently on RAF airfields and aircraft factories, that was to become known as the Battle of Britain. The name of the battle came from a speech made by Churchill in the House of Commons on 18 June in which he said that the Battle of France was over and the ‘Battle of Britain’ was about to begin.

The role of Bletchley Park and signals intelligence in tracking the German bombers and fighters attacking the UK is not widely known but the Air Section, which had a dual role as a GC&CS section and as a section of Air Intelligence, AI4f, was able to break the low-level codes used by the
Luftwaffe
to control the German bombers flying from their airfields in France to attack the UK. ‘Exploitation of this material for intelligence purposes
should have been a moderately straightforward process,’ said Bill Bonsall, a member of the Air Section who would later go on to become the head of its post-war successor GCHQ.

Bonsall was recruited to Bletchley by Martin Charlesworth, one of the dons who had been inculcated in the work of GC&CS at the start of the war but had stayed as President of St John’s College, Cambridge, to talent-spot potential codebreakers. He and another candidate were invited to Charlesworth’s rooms where Denniston and Tiltman were waiting to interview him. ‘They asked us if we were interested in confidential war work,’ Bonsall recalled.