5

The Wizard War

In the early hours of 5 November 1939, a parcel was left on the window ledge of the British Consulate in Oslo, in what was then still neutral Norway. Signed simply ‘A German scientist who wishes you well’, the parcel contained several typed pages which appeared to relate details of the latest German scientific research. This included information about radar equipment, new fuses for bombs and shells, the progress of the dive-bomber, the development of rocket technology, details of a large experimental establishment at Peenemünde on the Baltic, and a description of a radar aid to guide bombers at night, called ‘Y-Geraet’ (or ‘Y-Apparatus’). When it was passed on to Scientific Intelligence in London, it was received with much scepticism and it was thought that the document was a plant to confuse or mislead British scientists. It was ordered that copies of the report should be destroyed. In fact, as the war unfolded, one after another of the details in the document known as the ‘Oslo Report’ came real. The Report revealed that the war would be fought between scientists as much as between soldiers, sailors and airmen. Churchill called this ‘the Wizard War’, and the scientists and innovators he called up in the service of Britain were essential members of his War Lab.

Probably ever since human beings first struck an animal with a stone, they have tried to improve the sharpness of the flint or the destructiveness of the stone. Ever since men first used metal weapons to strike at their adversaries, they have tried to improve the efficiency and power of their arms. And certainly ever since firearms were first introduced in the late Middle Ages, gunsmiths have tried to improve accuracy, the rate of fire and the general destructive capability of their weapons. Leonardo da Vinci is often remembered for the genius of his art, but he actually devoted more of his life to the improvement of military machines for his patrons and the invention of new devices for destroying the enemy. In other words, the application of science has never been far from the development of the technology of war.

But around the time of the Industrial Revolution, the military and the world of science, the soldier and the scientist, became separated. As the profession of arms became a full-time professional calling, it developed its own mores, customs and practices. Soldiers became convinced that they, and they alone, understood the business of war and needed to get on with it without interference from outsiders who lacked their professional expertise. During the nineteenth century, soldiering became an inherently conservative profession. Officers whose decisions could directly result in the death of their men, and generals whose strategies could end in massive loss of life or national humiliation, did not want to experiment with new methods and ideas that might lead to even greater losses on the battlefield. Around these attitudes grew up the rituals of officer life associated with the world of soldiering in many Western countries – the customs of the regimental mess and the subtle but rigid social hierarchies of different regiments. Soldiering, at least as far as officers were concerned, generated a socially exclusive lifestyle based on tradition and the repetition of the same processes over and over again. In Britain, for example, it now seems astonishing how many admirals were reluctant to give up sail and embrace the transition to steamships. In the army, many generals continued to champion the value of cavalry units even as the world became dominated by the internal combustion engine. And with this conservative view on how to fight wars (it is often said that each new war is approached using the methods of the last), the unchallenged acceptance of command and authority became an inherent and vital feature of the military mind. While science was intended to challenge, to question and to change the world, the armies and navies of most developed nations chose to freeze their thinking, in well-established and proven systems. As Solly Zuckerman, an important player in this story, put it: ‘Where it is the habit of the scientist to question, it is that of the soldier to obey.’¹

This was the world that Churchill entered first at Sandhurst and then in the 4th Hussars, one of the elite cavalry regiments of the British Army. But as we have seen, Churchill was no model young cavalry subaltern. He read books to stretch his mind. Instead of fox-hunting during his long vacations, he travelled to distant military conflicts to get a taste of the action. Then he wrote about these experiences and even went so far as to question the decisions of his senior officers. Although Churchill entered the British Army at the peak of its Victorian mode of thinking, and although he enthusiastically took part in its last great cavalry charge, he did not possess the frame of mind required to progress to the top of the military system. His mind was too restless, and he was far too ambitious to settle for a career of slow and gradual promotion through the military hierarchy.

When he returned to the military world as First Lord of the Admiralty in 1911, Churchill was much more associated with radical thinking, so it was not surprising that his fertile mind found new ideas appealing. Hence his enthusiasm for the Royal Naval Air Service, his vigorous support for the transition from coal- to oil-fired turbines, and when war came his encouragement for a variety of new technologies – from Q-ships to the tank to the code-breaking carried out in Room 40. Churchill was deeply upset and offended when his idea for a mechanical device to cross the barbed wire of no man’s land and penetrate the enemy’s trenches (what became the tank) was rejected by the army as ‘not likely to lead to success’. His anger is still there in the pages of The World Crisis, written some ten years later.² When it came to his spell as Minister of Munitions in the last fifteen months of the war, again he was eager to find new systems and new ways of operating that would increase output and efficiency. And in the post-war era he sought out more new technologies and new strategies to devise a role for the RAF to act as a form of imperial police force, and to establish new accords with old enemies, as in the Irish Treaty negotiations. Churchill was always up for a challenge, and nothing was sacred to him in the traditional world of military thinking. As a young man, he had been deeply opposed to stuffy, closed-minded, conservative military commanders. He had come across them in India, the Sudan, in the Boer War and at the Admiralty. And in many of his books he had written of the need for vigorous and inventive thinking. ‘Nearly all the battles which are regarded as masterpieces of the military art … have been battles of manoeuvre in which very often the enemy has found himself defeated by some novel expedient or device, some queer, swift, unexpected thrust or stratagem.’³ In a sense, this statement sums up his quest for new and radical solutions to military problems. By the 1940s, this inevitably meant some sort of marriage between the scientist and the soldier.

Churchill, of course, was the first to accept that he himself understood little about science and almost nothing about mathematics – the subject he had found so difficult to master at school, while his failures in maths exams had nearly prevented him from qualifying for the army. So it was that during the late 1920s Churchill developed a friendship and deep respect for Professor Frederick Lindemann, known always as simply ‘the Prof’. Lindemann was in many ways the most unlikely member of Churchill’s court at Chartwell. He was a vegetarian, and a non-smoking teetotaller! He always looked the same, dressing in a dark formal suit. He wore evening dress at dinner. And he always took a bowler hat and umbrella when going out, whatever the weather. He was an eccentric who seemed to enjoy annoying people. Whenever he crossed the road, he never stopped to look, he would just step off the pavement, waving his umbrella, and charge through the traffic (there was less then than today). In conversation, he liked to be blunt and provocative. When someone at Churchill’s dinner table at Chartwell before the war asked him for a definition of morality, he replied: ‘I define a moral action as one that brings advantage to my friends.’ Clementine whispered to the person who had asked the question: ‘Doesn’t the Prof sometimes say dreadful things?’⁴

But Lindemann was a physicist of great standing and international renown. He had known Einstein before the First World War while carrying out research in Berlin. He had joined the Royal Aircraft Establishment at Farnborough in 1915 where he had carried out important work, including finding a way for pilots to pull out of a spin, which in those days was nearly always fatal. He is supposed to have learned how to fly in order to carry out tests to see if his mathematical calculations about this actually worked in practice. They did. In 1919, he went to Oxford as Professor of Experimental Philosophy. At that time, Oxford science was way behind that of Cambridge, and Lindemann gave a huge boost to the work of the Clarendon Laboratory, which had been severely neglected.

Churchill later described Lindemann’s value as one who could explain to him ‘in lucid, homely terms what the [scientific] issues were’. Lindemann’s vast and wide-ranging scientific knowledge and his natural self-assurance enabled him to sum up almost any scientific question for Churchill, whether it be the potential power of the atom or (as we have seen) problems with the standard-issue Mills grenade. ‘There are only twenty-four hours in the day,’ Churchill wrote, ‘of which at least seven must be spent in sleep and three in eating and relaxation. Anyone in my position would have been ruined if he had attempted to dive into depths which not even a lifetime of study could plumb. What I had to grasp were the practical results.’⁵ And this was what Lindemann provided him with. His memos to Churchill were usually just two pages long, double spaced in large print. He always tried to condense even the most complex and demanding scientific ideas into these bite-sized chunks for his boss’s consumption.

When Churchill returned to the Admiralty in 1939, he asked his friend to come with him, and Lindemann left Oxford to do so. When Churchill became Prime Minister, the Prof went on to be one of the key players in his War Lab. He was made head of the newly created Prime Minister’s Statistical Branch, with a tiny team of some six or seven economists and a scientist. It acted like an independent think-tank for Churchill and had a roving commission to dig into any aspect of wartime government and administration. Lindemann met with Churchill almost daily, advising him on scientific matters, military issues, logistical problems and even the economy. Most weekends, he joined Churchill and his entourage at Chequers. And he sometimes accompanied Churchill when the Prime Minister travelled abroad. Lindemann sent Churchill about two thousand memos during the war, equivalent to roughly one per day. His biographer said his role as scientific adviser to Churchill gave him ‘power greater than that exercised by any scientist in history’.⁶ Inevitably, with such a difficult and combative man, this would prove controversial. And, equally inevitably, with his prickly and vain personality, often coming across as pompous and stiff, there would be major fallings-out between Lindemann and other key scientists.

But Churchill was worried that the Whitehall establishment would be slow to respond to new and dramatic developments in science, and that good advice would take too long to percolate up to him. So he wanted Lindemann at his side not only to explain in a way he could understand what the new science might be, but also to advise him on what else was needed in the wizard war. The Statistical Branch prepared albums of tables and charts to illustrate at a glance the strength of military units in various theatres, and to keep a running record of shipping losses in the Atlantic. Churchill was proud of these albums and used to show them off to the King and, later, to President Roosevelt.⁷

Back in the early 1930s, Prime Minister Stanley Baldwin had said in Parliament: ‘the bomber will always get through’.⁸ By this, he meant that there was no effective means of defence against enemy bombers. In the age of appeasement, it became government policy simply to accept the inevitability that Britain would be bombed in a future conflict. Churchill and Lindemann did not accept this defeatist attitude and Lindemann wrote to The Times on 8 August 1934:

Sir, In the debate in the House of Commons on Monday on the proposed expansion of our Air Forces, it seemed to be taken for granted on all sides that there is, and can be, no defence against bombing aeroplanes … That there is at present no means of preventing hostile bombers … I believe to be true; that no method can be devised to safeguard great centres of population from such a fate appears to me to be profoundly improbable … To adopt a defeatist attitude in the face of such a threat is inexcusable until it has definitely been shown that all the resources of science and invention have been exhausted.⁹

Lindemann’s letter acted like a wake-up call. Something had to be done to develop defensive means against the bombing of Britain. This was where the wizards came in.

A committee was set up to investigate how scientific and technical advances could aid the detection of enemy aircraft. Sir Henry Tizard was asked to chair it. Tizard has been called one of Britain’s greatest defence scientists.¹⁰ He had begun as a chemist but had given up pure research and moved across to find ways of applying scientific advances to practical problems. Tizard was an excellent chairman and was known for asking clear and brilliant questions. At this point he was the rector of Imperial College, London, to which he had given a great boost – just as Lindemann had improved the standing of Oxford’s Clarendon Laboratory. In many ways, Tizard’s career closely paralleled that of Lindemann. Indeed, they had known each other in Berlin before the First World War and had become friends. But they had very different views on how to bring science into the mainstream. Tizard committed himself to public administration and worked tirelessly on several government committees. Lindemann attached himself to Churchill and saw political alignment as the way forward. When Lindemann pressed the Air Ministry to set up a committee to explore the science of air defence and discovered that Tizard was already running such a committee, he took this as a great personal affront by both Tizard and the ministry. Instead of working together, Lindemann fell out with Tizard. And once he held a grudge, the Prof was not one to forgive.

In this context, significant developments were made in Britain in Radio Detection-Finding, radar. When Churchill joined the Air Defence Research Committee in 1935 he first learned about the early development of radar from Tizard and others. Radar’s origins lay in the bizarre quest to find a ‘death ray’ that would send enough energy along a beam to destroy an enemy aircraft. In 1935, Robert Watson-Watt, the superintendent of the National Physical Laboratory’s Radio Research Station at Slough, was asked to investigate this. He very quickly proved that the amount of energy needed was so vast that the death ray would remain firmly in the realms of science fiction rather than science fact. But Watson-Watt was one of the out-spoken mavericks of British science in the 1930s, with a strong sense of how science could be used to transform the future. He observed that radio waves will bounce off an aircraft and after tests using the BBC’s short-wave radio transmitters at Daventry, he devised a system for measuring the position of a flying object. The Air Ministry quickly grasped the potential of this invention to give an early warning of the approach of enemy raiders, an advantage that in the age of ‘the bomber will always get through’ would prove vital.

Air Marshal Hugh Dowding was at this time in charge of RAF Research and Development, and he was impressed. He agreed to put up ten thousand pounds, a substantial sum, of research funding for the device to be tested. In simple surroundings first at Orfordness on the Suffolk coast and then at nearby Bawdsey, Watson-Watt and his small team of scientists developed one of the great inventions of the twentieth century. They began to find ways of measuring first the distance, then the height and finally the bearing of aircraft using radio transmitters and a cathode-ray tube. Despite the low level of defence spending, radar (or RDF) developed rapidly under Watson-Watt and both the army and the navy began to show an interest in his experiments as well. As we have seen, RAF Fighter Command when Dowding took it over developed a plan for the organisation of the air defence of England based on the construction of the Chain Home radar system. But the principal achievement of Dowding and his team of scientists was to integrate the scientific side with the operational, to filter and process the information gleaned from the new science into an effective battle plan. Tizard played a vital role in this development during a series of tests at Biggin Hill airfield in Kent, in the late 1930s. He calculated the angle at which the faster fighters needed to be directed in order to intercept the slower bombers. This became known as the ‘Tizzy angle’ and was used until the 1960s, when computers took over such calculations. The whole process marked a subtle but important shift. Pilots, who had traditionally operated under their own rules of patrol and observation, were now scrambled and directed to the enemy by their controllers, who acted according to strict scientific principles in reading, interpreting and predicting the Luftwaffe’s flight path. This has been described as being ‘of crucial importance in the new service–scientist relationship’.¹¹ During the Battle of Britain, radar literally meant the difference between victory and defeat. It was not the only element that helped bring victory to the RAF. But without radar, defeat would have been certain.

In the run-up to war, several senior scientists realised the important role science would play in the future conflict. Fearing that the government was not doing enough to prepare for war, they drew up a list of seven thousand scientists, some working in universities, others in industry. Each scientist’s name and area of expertise were entered on to a card index known as the ‘Central Register’. By this simple method, physicists, engineers, chemists, biologists, astronomers and botanists were all carefully listed. So, for instance, when the Merchant Navy needed a specialist in maritime refrigeration, the right person could be quickly found. Although many senior officers in the army and navy were still sceptical about how these scientists would fit into military work, the Air Ministry was more welcoming, as it had been with the integration of radar into an operational defence plan. The RAF was the youngest of the three services and needed science in obvious ways to improve its performance in the air. So it is not surprising that this new breed of scientist, known as the ‘boffin’, should have been welcomed first by the nation’s aviators. ‘Boffin’ was the affectionate term that came into popular use during the war to describe a scientist known for his inventiveness, his persistence and his ability to come up with weird and wonderful solutions to problems. (They were nearly all men, as women received little encouragement in the sciences at this time.) Sometimes they joined the military, often they remained civilians, operating through a range of government advisory committees. There was a lot of potential for tension here. Senior military officers were usually drawn from the gentry or the upper middle classes and were of a conservative disposition. The boffins usually did not enjoy much social status, came from a variety of backgrounds, and were often radical in their approach. Nevertheless, the boffins would bring much to the military over the next few years, and without doubt they contributed significantly to the Allied victory.

One of the greatest triumphs of science in the war was the deciphering of German codes. In the 1930s, the German military had developed a form of top-secret communication using the Enigma machine. This was an electro-mechanical typing machine which was able to encode every letter of every message via a series of rotor blades. The scrambled message was then sent as a conventional radio signal. The Enigma machines for the various parts of the military were slightly different in their configurations, but the basic operating principle was the same. The operators would reset the rotor blades at the back of the machine every twenty-four hours, so that messages would be encoded according to a different formula each day. The German military were convinced that their Enigma codes were secure because, although it was theoretically possible for the enemy to decipher a message, it was reckoned that it would take so long that by the time it had been done the rotor blades would have been reset and a new code created. The Germans therefore put total faith in their Enigma codes, and the High Command communicated regularly with the Wehrmacht and the Luftwaffe, issuing orders and receiving field reports filled with precise details about locations, the strength of units, casualties, operational plans, and so on.¹²

Before the war, Polish Intelligence had captured an Enigma instruction booklet and had even got its hands on an Enigma machine, and so had been able to crack the German code system. In the summer of 1939, French Intelligence and the British Secret Intelligence Service started to get interested in this. Just before the outbreak of war, the Government Code and Cypher School moved its staff of about one hundred cryptographers to Bletchley Park, a country-house estate to the north of London. Additional teams of mathematicians were then recruited to work there, many from nearby Cambridge University. After the defeat of Poland and then France, Bletchley became the principal Allied centre for code-breaking. The amount of work that went on here soon outgrew the mansion house and stables, and dozens of brick huts were built across the grounds of the estate. Within a few years, seven thousand men and women were working at Bletchley, with even more at a series of outstations around the country, from Dorset to northern Scotland. They included radio operators, mathematicians, decryptologists, interpreters, and hundreds of clerical support staff working on the central index, many of whom came from the Women’s Royal Naval Service.¹³

Of all the many extraordinarily brilliant personalities who worked at Bletchley, Alan Turing was one of the most exceptional. A top-level mathematician and mechanical engineer, he was a fellow of King’s College, Cambridge, and had written a pioneering paper on computable numbers before the war. He was only in his late twenties when he arrived at Bletchley, with boyish looks but a totally dishevelled and eccentric air. His trousers were often held up with an old tie, he had stopped shaving regularly, his hair was scruffy and he spoke with a stutter. He was painfully shy and developed the habit of working continuously for days at a time before collapsing in exhaustion. His military masters never really understood him. But he ran Bletchley’s famous Hut 8 where he helped design the first ‘bombes’, huge electrical machines six-foot-by-seven, consisting of thirty rotating drums that ran through thousands of letter possibilities at high speed to find the correct match of plain text with encrypted letters. Out of these later in the war came Colossus, the world’s first operational computer, which could run through the tens of millions of computations that were necessary to decode some of the most complex messages. Initially it took days to decode a signal, but Colossus reduced this to hours and ultimately to minutes. It was a stunning breakthrough and Turing went on to help found the post-war computer industry. Hounded for being gay, he committed suicide in 1954 by biting on a poisoned apple.

Although exceptional, Turing was only one of many eccentric and remarkable characters working as code-breakers at Bletchley Park. Gordon Welchman, another pipe-smoking, studious Cambridge mathematician, was one of the first to recognise the scale of the task that faced code-breakers who had the potential to listen in to the German high commanders talking to each other on a daily or even an hourly basis. When more code-breakers were needed, he drove off to Cambridge in his Austin 7 and rounded up former colleagues and students to join his team. Peter Twinn, an Oxford mathematician, found that he was resented by the old school of cryptologists, who were all classicists and suspicious of what these bright young mathematicians could contribute. Stuart Milner-Barry was an international chess champion who was recruited at the start of the war. Josh Cooper was one of the strangest. He had the peculiar habit of putting his right hand behind his head and stroking his left shoulder when he was thinking. He was also known for every now and again missing his chair when he went to sit down and landing up on the floor. Mostly the newcomers were young, in their mid-twenties, but there was also a smattering of older men who had been members of the Admiralty’s Room 40 in the First World War. Nigel de Grey was one of the most celebrated Great War code-breakers. Frank Birch, another Room 40 veteran, had combined life as an academic with a career on the pantomime stage. Some of the newcomers were women, like Diana Russell Clarke who worked in the Hut 6 Machine Room. She was renowned for driving her Bentley sports car at high speed through the local country lanes. Linguists Phoebe Senyard and Barbara Abernethy were also among the earliest recruits.

Today, the work of Bletchley Park (or Station X, as it was known) is famous. There have been novels, movies and TV series about the place. But between 1939 and 1945 it was the most highly secret operation in the entire war effort. Very few people, including most of the staff at Bletchley themselves, had any idea how crucial this code-breaking work was. The recruits were placed in a small group and got on with their own tasks, totally unaware of what was happening in any other group. Most of the new arrivals were selected because they were thought to be 100 per cent reliable, but on arriving at Bletchley many were often still met by a security officer who would draw his pistol. Everyone was told that he or she must never breathe a word of anything they did or knew about to anyone else. If they did, they were told, the officer would personally come and shoot them. The secrets of Bletchley Park lived on long after the war. It was only in the mid-1970s that stories began to emerge about the code-breaking that went on there and its importance to the Allied victory.

The information gleaned from breaking the German codes and listening in to the Enigma communications between field units and their headquarters was known generically as ‘Ultra’. It began to come on line within weeks of Churchill becoming Prime Minister. The excitement of reading deciphered messages direct from the enemy appealed greatly to Churchill, just as it had in the First World War. He really enjoyed the magic and the mystery of it.¹⁴ Instead of reading summaries of the messages, he asked to receive the information raw, as it had been decoded and translated. He did not like the idea of it being watered down or distorted to give him a rosier picture than was really the case. Every day, wherever he was, a special box in faded yellow leather was delivered to Churchill by a messenger from the Secret Intelligence Service (SIS). In this box were the latest decrypts, the decoded messages. Only Churchill held the key to this box, on his keyring. The boxes came to him from the director of SIS, the man known as ‘C’ (later the inspiration for ‘M’ in the James Bond stories written by Ian Fleming, who worked in Naval Intelligence during the war). ‘C’ was Colonel Stewart Menzies, who ran SIS throughout the war and into the early 1950s. Desmond Morton coordinated the flow of Ultra from Menzies, but it all went directly to Churchill, who returned it after reading. To protect the source of this information, the code name ‘Boniface’ was used, suggesting to anyone who might by accident hear about it that it had been supplied by an agent, a spy operating somewhere inside Germany. Even Churchill’s closest aides knew nothing about these decrypts. Only a tiny number of senior ministers and the Chiefs of Staff and their deputies, about thirty people in all, knew of the existence of this highly valuable top-secret intelligence. Over the next few years, the mass of information decoded from the Wehrmacht, the Luftwaffe, the Abwehr (German Military Intelligence) and even from the German police and railways revealed much about the enemy’s military intentions. The German Navy used an even more sophisticated Enigma system with extra rotor blades, adding immensely to the challenge of the code-breakers. Only when these naval codes were finally broken in December 1942 did the Battle of the Atlantic begin to turn in Britain’s favour. At the time, Churchill called the code-breakers ‘the geese that laid the golden eggs and never cackled’.¹⁵

In September 1941, the Prime Minister made a personal visit to Bletchley Park to inspect the ‘geese’ for himself. Even he was surprised at the casual dress and eccentric behaviour he saw. He is supposed to have said to Menzies: ‘I know I told you to leave no stone unturned to get staff but I didn’t expect you to take me literally.’¹⁶ He made a short and emotional speech to the code-breakers, telling them how important their work was. But because so few people in senior government positions were allowed to know about the work going on there, Bletchley Park was constantly turned down when it put in bids for much-needed extra staff and resources. By this time the volume of work coming through required a major expansion. So, a month after his visit, Turing, Welchman and two other leading code-breakers wrote directly to Churchill, telling him: ‘We think you should know that this work is being held up, and in some cases not being done at all, principally because we cannot get sufficient staff to deal with it.’ They went on to appeal above the heads of their bosses direct to the Prime Minister: ‘For months we have done everything that we possibly can through the normal channels and we despair of any early improvement without your intervention.’ They asked for additional typists, more clerks, and for the removal of various bottlenecks. When he received the letter, Churchill sent a minute to General Ismay, saying: ‘Make sure they have everything they want as extreme priority and report to me that this has been done.’ Then he stamped the minute with the red ‘Action This Day’ sticker. Within a month, the essential expansion at Bletchley Park had begun. The Ministry of Works started erecting new buildings and a recruitment programme for two thousand extra staff was launched. Once again, Churchill’s personal intervention had made the key difference.¹⁷

Before the Battle of Britain had got fully under way and the genius of radar had proved its worth, the boffins again came to the aid of the military. A young research scientist who had worked for Lindemann at Oxford, Dr R.V. Jones, warned the Prof that the Germans had developed a sophisticated system of beams to guide their bombers to their targets. The beams could be used by day or night and in any weather conditions. Lindemann reported this warning to Churchill, who instantly recognised its importance. Without waiting for the slow-moving bureaucracy to assess the situation, Churchill called an urgent meeting on 21 June in the Cabinet Room. The new Minister for Air, Sir Archibald Sinclair, and the Minister for Aircraft Production, Lord Beaverbrook, were there along with Tizard, Lindemann, Watson-Watt and several senior RAF figures. Jones was summoned to attend the meeting but when he got into work that morning and found the message calling him to the Cabinet Office he thought it was a practical joke. As a consequence he was about half an hour late. Soon after he arrived, Churchill asked him to outline the position. Jones was only twenty-eight years old, but undaunted by the top brass that now confronted him he launched into an explanation of how for some time he had been picking up reports that the Germans had developed a secret weapon, a new system of night bombing, on which they placed great hopes. It seemed to be linked to the code word Knickebein, which somewhat mysteriously translated as ‘crooked leg’. A bomber had crash-landed earlier in the year and the phrase ‘Knickebein beacon’ had been found in some documents. Captured Luftwaffe crew were interrogated and revealed the use of special new radio equipment. More shot-down aircraft were searched and further references to Knickebein were found, including one linking it to a location in Cleves, in north-western Germany. Meanwhile, aerial photography had revealed the existence of several strange towers that did not look like conventional radio beacons. After Luftwaffe prisoners of war were overheard saying, ‘They’ll never find where it is,’ Jones had the idea that maybe this new device was contained within the existing system that enabled a pilot to land at night or in bad weather by tuning in to a beam. Sure enough, this equipment proved to be far more sensitive than was needed for landing purposes, and when an RAF aircraft tried it out, the plane picked up a whole series of signals linking it to a beam. It was then that Jones realised these could be used not for landing, but for guiding bombers to their targets.

Churchill and the distinguished gathering of senior officials listened to Jones as he told his story. Churchill later wrote ‘For twenty minutes or more he spoke in quiet tones, unrolling his chain of circumstantial evidence, the like of which for its convincing fascination was never surpassed by the tales of Sherlock Holmes.’¹⁸ Then there was a discussion around the table. Some of those present were incredulous. They argued that such a system was unnecessary and asked why the Luftwaffe pilots did not simply navigate by the stars, as RAF crews were trained to do. But Churchill, on the advice of Lindemann and against that of Tizard, who was sceptical about the existence of the beams, was ready to accept that the Germans had devised such a system. As the argument continued, Churchill grew angry and banged his fist on the table.¹⁹ He ordered that countermeasures were to be investigated as a matter of priority. Jones went back to his desk in the Air Ministry to coordinate what became known as the ‘Battle of the Beams’.

Conventional wisdom had it that short-wave radio beams did not have the accuracy to guide aircraft over the distances involved, that they would disperse like the beam of a searchlight with the curvature of the earth. But Jones persisted, and by flying with the captured German equipment, RAF pilots discovered a beam emanating from Cleves and directed on Derby in the East Midlands. This sent a cold chill down the spines of those involved. Derby was the location of the Rolls-Royce factory producing Merlin engines for Spitfires – vital for the Battle of Britain. This was probably the single most important target in Britain. Identification of this beam produced a near panic that the Germans could now bomb at night factories of such major importance to Britain’s war effort. Scientists from the Air Ministry and the Telecommunications Research Establishment near Swanage in Dorset worked together at full speed. By the middle of August, all the Knickebein transmitting stations across northern France had been identified (the Cleves station had moved to Calais). Then the boffins found ways to jam the beams electronically, so the bombs would be dropped not on the intended targets but on open fields some fifteen or twenty miles away. The counter-measures were known by the code name ‘Aspirin’, as they helped clear the headache caused by Knickebein. By the time the Blitz began in earnest on 7 September with the big raid on the docks and East End of London, the first phase of the Battle of the Beams had been won.

Of course, the Germans soon realised that their beams had been identified and were being distorted. A new chapter in the scientific war unfolded when the Luftwaffe transferred to a new system called ‘X-Geraet’ (or ‘X-Apparatus’). This was a more sophisticated device that used five very high-frequency, short-wavelength beams to guide the aircraft. When these beams intersected with cross-beams, a trained navigator could identify a target with great accuracy – it was estimated down to about one hundred yards. This system was used by only one formation, a special ‘Pathfinder’ group, Kampf Gruppe 100. The planes of KGr 100 would identify the target and drop incendiaries and the rest of that night’s bombing force would then aim their explosives at the area of the flames.

On the evening of 5 November 1940, a Heinkel from KGr 100 crashed on the beach at West Bay, near Bridport in Dorset. As the sea lapped around the bomber a dispute ensued between the army, who turned up to salvage it, and the navy, who claimed that as it had landed in the sea the prize was theirs. As a consequence, the vital electronic equipment was initially lost and it took several days to find it. Even when it was finally recovered it proved difficult to piece together how it worked. It seemed the Germans transmitted eight beams, but only five of these were used in each raid. And they used two different types of signal, which the British called ‘fine’ and ‘coarse’. But jamming or distorting the beams still proved impossible.

Using Ultra decrypts and a close study of how the beams were set up, by mid-November the boffins knew that a big series of raids was coming under the code name ‘Moonlight Sonata’. But they were unable to predict the targets and still could not jam the beams. Sure enough, on the night of 14 November, the Luftwaffe mounted its biggest raid yet outside London when it bombed Coventry. The raid was one of the worst of the Blitz. In addition to the hundreds of civilian casualties, the cathedral and more than twenty factories were destroyed. A persistent myth still surounds this raid that Churchill knew the target was Coventry but failed to warn the city or order the jamming of the beams so as not to give away the fact that British boffins understood how the German system worked. It is clear from the evidence of those working long hours to understand and distort the beams that this was not the case. In fact, Churchill thought the raid was heading for London. He ordered his secretaries into underground shelters, telling them they were too young to die. Churchill himself could not sleep and spent much of the night on the Air Ministry roof, looking out for the expected bombers.²⁰

By early 1941, a successful means had finally been found to block the X-Geraet system. The stronger counter-measures this time were known by the code name ‘Bromide’. The Germans would turn on the beams in the evening before a raid and from this Jones and his team were eventually able to identify what that night’s target would be. But the Germans, once again, soon developed yet another device, the Y-Geraet, or Y-Apparatus, an early version of which had been described in the Oslo Report. It used a highly sophisticated form of radar to guide an aircraft to its target. This system was identified and disrupted by the British boffins more quickly. In May 1941, it is thought that the twisting of these signals inadvertently led the Luftwaffe to bomb Dublin, in neutral Ireland, in error. The see-saw war of one side gaining an advantage, followed by the implementation of counter-measures to block this, continued until that May, when the Blitz on Britain was lifted as the majority of the Luftwaffe were sent east to a new target, the Soviet Union. Churchill estimated that the combination of British counter-measures and simple Luftwaffe inaccuracy meant that 80 per cent of German bombs missed their targets. This was, as he said, ‘the equivalent of a considerable victory’.²¹ Of course, this meant one in five bombs still hit home, and they caused dreadful losses throughout the winter and early spring of 1940–1. But without the boffins’ work, the damage would have been much worse. The Battle of the Beams had proved to anyone who cared to doubt it that this would be a scientific war. But Churchill had already taken a major step to ensure that Britain would be on the winning side.

One of the unfortunate consequences of the big meeting held on 21 June, when Jones had first related to Churchill and the RAF bosses the story of the German Knickebein beams, was the resignation of Sir Henry Tizard. With Lindemann’s close association to Churchill, their old rivalry re-emerged after he became Prime Minister and Tizard realised his position had become untenable. He also accepted that in not backing Jones in his suspicion that the Germans were using beams he had been wrong. He withdrew from his position at the apex of many government defence committees. But Churchill, unlike Lindemann, was not a man to hold a grudge. He recognised Tizard’s ability and soon came up with a new mission for him.

During the summer of 1940, Churchill worked hard to persuade Roosevelt to increase the US commitment to the British war effort. We have seen that he was partially successful in this but at the end of July, Churchill personally took a dramatic and courageous decision that would have long-term consequences for Anglo-American cooperation during the war and for long after. With the threat of invasion and the possibility of defeat still real, Churchill decided to share Britain’s scientific secrets with the Americans and the Canadians. Behind this extraordinary decision lay the idea that if Britain were defeated, then at least the New World could continue the fight using the latest technological advances. It was not an altruistic gesture. It was motivated by the desire to bring America further into the war. But for a nation at war to supply its top secrets to a non-belligerent country was an act of faith unique in world history. Churchill asked Tizard to chair the vital mission to the United States that would offer up those secrets.

Tizard was delighted with his new task. He hoped that he would succeed in bringing ‘American scientists into the war before their Government’ and that he could encourage the Americans to reciprocate by sharing some of their advances with Britain.²² He gathered together a series of papers representing the most advanced thinking of British scientists on miniaturised radar which was being developed for air-to-air use, chemical warfare and on explosives. In addition, he boxed up and took with him actual examples of a variety of new devices. These included three power-driven gun turrets that were later used in bombers; proximity fuses that ignited when they came close to an aircraft, which the United States were to build in huge numbers; and a new predictor for the multiple-firing Bofors gun. But most important of all was a small black box containing the jewel in the crown of British science in the summer of 1940, the cavity magnetron.

The cavity magnetron had been developed by two scientists at Birmingham University, Professor John Randall and Dr Harry Boot, earlier in 1940. Radar, despite its great value, was limited by the inability to send out really short-wavelength radio signals. The cavity magnetron was a valve that overcame this problem by turning high voltages into short-wave signals of immense power. When combined with a receiving valve, the cavity magnetron revolutionised the power and range of a radar set almost overnight. Radar could now pick up and identify the movement of people, the positions of cliffs to assist in the radar navigation of naval vessels, and even the location of the conning tower of a submarine. And the way was opened for its use within aircraft and ships for blind navigation during fog or darkness. And radar’s range was extended from forty or fifty to well over a hundred miles. The cavity magnetron was, literally, a war-winning device. When the box containing it was opened and it was shown off to a group of American scientists in a Washington hotel, they were almost blown away by what they saw. The official historian of the American scientific war later described this as nothing less than ‘the most valuable cargo ever brought to our shores’.²³

Churchill’s decision to share Britain’s secrets with America had long-term consequences of immense importance. A Scientific Office was opened in Washington to coordinate the further exchange of scientific ideas. Delegations of senior American officers and top scientists travelled to Britain to discuss ways of collaborating should the United States enter the war. America not only became a closer ally (Churchill’s primary objective) but could now put its vast industrial muscle behind the development and manufacture of some of the latest scientific devices on a scale way beyond anything that was possible in Britain for the rest of the war.

In the summer of 1940, after France had fallen and with the Battle of Britain raging, it became obvious that heavy air raids would soon be made on Britain. But the state of the nation’s anti-aircraft defences was poor. There were too few guns, and anyway the process of trying to hit a fast-moving target when it would take many seconds for the ack-ack shell to reach the right altitude, was still very hit and miss (mostly miss). Giant concave sound detectors were used to try to establish the height of enemy aircraft, but these were hopelessly inefficient. The officer in charge of Anti-Aircraft Command, General Frederick Pile, was an imaginative man keen to find any means to improve the accuracy of his gunners. After discussions with Tizard, it was decided to recruit a group of young scientists from the universities and industry from the Central Register drawn up before the war to tackle the problem. They were led by Professor Patrick Blackett, a leading physicist from Cambridge who had been an officer in the First World War and understood the army mentality. The team became known as ‘Blackett’s Circus’.

The Circus immediately got to work to try to bring scientific principles into the operation of the anti-aircraft batteries. Radar was used to try to predict the path, speed and altitude of enemy aircraft. But unlike the radar used by the RAF in the tall towers of the Chain Home sites, the portable radars used by the army alongside the ack-ack guns were never far off the ground and so were subject to massive interference from nearby buildings and even hills and valleys in the surrounding landscape. Experiments were carried out and it was discovered that placing wire netting around the radars provided a uniform reflecting surface which cut right back on interference. Within weeks, the army had requisitioned nearly all the available stocks of wire netting in the country and this was now laid out around the mobile radars at the batteries.

The second task was to link the guns’ firing control with the radar signals to ensure that the batteries could fire at the position the enemy aircraft were going to arrive at in the number of seconds it took for the shells to reach the correct altitude. Masses of statistics were gathered as night after night the men of Blackett’s Circus looked for ways to improve on the gun sighting mechanisms. Work was done in Richmond Park to calculate the optimum layout for a battery of guns and the best way to concentrate fire. Throughout the winter of 1940–1, as German bombers flew over almost nightly to blitz the cities of Britain, the men of Blackett’s Circus observed the enemy raiders and worked out the best way to hit them.

This process of applying scientific, often mathematical, principles to observe, assess, review and ultimately to improve military operations was called Operational Research. It began to play an important part in the war effort and soon spread from the army to the navy and the RAF. All the services had their traditional ways of doing things, and the boffins of Operational Research were able to observe and assess these and sometimes find more efficient ways of achieving results. In 1941, Blackett summed this up by saying that Operational Research could encourage numerical or scientific thinking on operational matters in order ‘to avoid running the war on gusts of emotion’.²⁴ This was at the heart of the wizard war: that scientific analysis could achieve better results than the time-honoured, traditional way so valued by soldiers, sailors and airmen.

Blackett himself went on to work for the navy and his Operational Research team helped in the deadly Battle of the Atlantic. It was found that aircraft painted white rather than the traditional black were more difficult to see from the sea. After the planes of Coastal Command were repainted, the number of U-boat sinkings increased. It was also discovered that something as simple as resetting depth charges to go off at twenty-five rather than a hundred feet resulted in many more kills. Indeed, losses went up so dramatically that captured U-boat crews said they thought the Royal Navy had developed a new weapon against them. At the height of the Battle of the Atlantic, Churchill became so concerned about the U-boat menace that he held fortnightly meetings at Downing Street which Blackett would attend in order to pass on the latest summaries and observations from his team (see Chapter 7).

The RAF had already embraced a form of Operational Research with the integration of radar technology into Fighter Command. The filter rooms which processed the inflow of information about the approach of enemy bombers and the command centres with their plotting tables and the movement of markers across maps that enabled orders to be sent to scramble the fighter squadrons had all been planned before the war. Soon Bomber Command established its own Operational Research unit, which again came up with a number of suggestions for improved operational efficiency. It was calculated that massed bomber attacks had more impact than a large number of scattered attacks. This thinking led to ‘thousand-bomber’ raids from May 1942. Scientists analysed how planes were shot down. Research found that most bombers returning from sorties had only one or two shell holes and were not structurally damaged. It was realised that most planes went down because of fires in their fuel tanks or the ignition of petrol vapour generated during a long flight. If an inert gas like nitrogen could be injected into the fuel tanks, then they would be less likely to burst into flames if hit by shrapnel from anti-aircraft fire. This discovery had long-term consequences, but only a limited improvement was possible during the war.²⁵

Operational Research units were created in RAF commands overseas. One important unit was set up in Cairo to advise on issues relating to the war in North Africa and over the Mediterranean. But there was a shortage of scientists, particularly mathematicians, so many young men straight from university were put into uniform and rushed out to the Middle East.²⁶ From here, important work was done on improving Allied operations in the Mediterranean by assessing the strike rate of bombs versus torpedoes against enemy ships (torpedoes had a higher success rate), and discovering the best way to find and sink U-boats. Later, this group learned that orange life-vests and life-rafts were easier to spot in the sea than the traditional yellow ones. This apparently simple discovery would save the lives of hundreds of downed airmen long after the war was over.

The Operational Research teams were only ever advisers. They were often placed in command centres and worked alongside staff officers. Their research sometimes confirmed that the traditional ways of doing things were the best. But when they did come up with new recommendations it was still up to the generals, admirals and air chiefs to decide whether or not to implement them. The fact that the military commanders often did follow the scientists’ advice is a sign of the changing balance between science and the military. The wizards were having a bigger impact than anyone could have imagined at the start of the war.

Another key player in Operational Research was Professor Solly Zuckerman. He had started his career as a zoologist and had done important research into the lives of apes and monkeys. When the war began, he was studying anatomy at Oxford. He and some colleagues wrote a short book, Science at War, in two weeks at the start of the conflict. Rushed out as a Penguin Special, this was almost a manifesto for the new science of Operational Research. Zuckerman went on to assess the effects of bomb blast on the human body and on buildings during the Blitz. He found that the body was far more able to withstand the blast than had previously been imagined and that most casualties were caused by indirect effects, such as the collapse of buildings. He began to calculate the number of casualties likely to be caused by the dropping of particular weights of bombs. Then he went to North Africa to survey bomb damage caused by air attacks on towns captured from the Germans and on military convoys crossing the desert. He used captured German documents as well as ground observations to make his assessments. Later, he looked at the impact of bombing on rail communications in Sicily and mainland Italy. His findings would play an important part in the debate about the bombing offensive which is dealt with in Chapter 8.²⁷

Of course, all of this work went on without the direct involvement of Churchill. But his support for men of science, his enthusiasm for change and new thinking, and his desire for the military to keep up with the work of the wizards, created the climate in which this particular seed could grow into a forest. This all stemmed from his War Lab. However, Churchill’s loyalty to the most prominent member of that group was both a hindrance as well as a help to the war effort.

In 1942, Churchill offered Lindemann a peerage and he became Lord Cherwell (the name by which he will be referred to from now on). Churchill also formalised his position in government by making him Postmaster General. But Churchill had become over-reliant upon Cherwell’s scientific advice. It’s unfortunate that Cherwell’s abrasive personality meant he fell out with so many distinguished men. And of all those who Cherwell vehemently opposed, Sir Henry Tizard was without doubt the greatest loss to the war effort. Churchill was usually a good judge of character, and he should have insisted that Tizard remain in the positions he had occupied with real distinction since before the beginning of the war. However, the Prime Minister’s friendship with Cherwell blinded him to Tizard’s qualities and he allowed Tizard to take a back seat after 1940. Without doubt this was a great loss to the British war effort. Tizard graciously summed up the position of the new science when he asked a parliamentary committee in February 1942, ‘What Prime Minister of England ever had a scientific adviser continually at his elbow?’ And he went on to observe of wartime Britain: ‘there is hardly a phase of the national life with which scientists are not associated. In fact a fighting friend of mine said that he could hardly walk in any direction in this war without tumbling over a scientist who had got in his way.’²⁸

But by this time, Tizard was under-utilised by the War Lab. He held a variety of minor roles, but none of them compared with his earlier work on air defence or his mission to the United States in the summer of 1940. This had been one of the most important scientific journeys of the war. But there was yet another secret that Britain still had to share with America, one which would have even greater long-term consequences.

Before the First World War, Albert Einstein had reasoned that atoms, the basic unit of matter, were held together by forces that if released could produce huge amounts of energy. In the late 1930s, German scientists in Berlin had succeeded in splitting the atom. Then, in early 1940, two German émigrés working in Britain on ideas about nuclear fission and how to release the power of the atom, Rudolf Peierls and Otto Frisch, made an extraordinary claim. They calculated that the amount of uranium needed in a bomb to unleash the energy equivalent to about a thousand tons of high explosives could be measured not in tons, nor in hundreds of kilograms, but was as small as one pound, less than half a kilogram. Their findings were passed on to Tizard, who at that point was still chairing the Committee for the Scientific Study of Air Warfare. Tizard discussed the possibility of finding some form of military use for this remarkable equation with Professor George Thomson in his rooms at Oxford. Thomson led a group of scientists nicknamed the ‘Balliol Beagles’ – so called because they always seemed to be chasing after the latest scientific ideas. Tizard decided to form a committee under Professor Thomson to examine the possibility of producing an atomic bomb. For the first time anywhere in the world, a government committee now began to consider the possibility of producing nuclear weapons.

Soon after Thomson and his small team of experts began their deliberations, a strange message arrived from an exiled German physicist working in Sweden. It read: ‘Met Niels and Margherita recently. Both well but unhappy about events. Please inform Cockcroft and Maud Ray Kent.’ Niels was Niels Bohr, the distinguished Danish physicist who had worked on atomic science before the war. Cockcroft was Sir John Cockcroft, a brilliant Cambridge scientist and Nobel prize-winner who was already a member of Thomson’s committee. But no one knew who Maud Ray Kent was. It was decided that the message was probably cryptic and could possibly be an anagram for ‘Make Ur Day Nt’ – a clue that the Germans were developing their own atomic bomb and that the British needed to speed up. Thomson’s committee was renamed the Maud Committee and increased the pace of its work through the summer, autumn and winter of 1940–1.

In July 1941, the committee submitted its report, concluding that it was possible that an effective atomic bomb could be produced within two years. When Cherwell read the report, he was sceptical as the science was still unproven and the production of an atomic bomb would involve a massive reallocation of resources that were more profitably committed to other wartime technologies. However, he concluded to Churchill: ‘I am quite clear that we must go forward. It would be unforgivable if we let the Germans develop a process ahead of us by means of which they could defeat us in war.’²⁹ Churchill agreed with the need to keep ahead of anything the Germans might be developing, so he set up a top-secret organisation under the code name ‘Tube Alloys’ to develop a nuclear bomb.

However, far more important than the creation of the British project was Churchill’s agreement to forward the Maud Report to the Americans. The report was filed away in the United States for several months until James B. Conant, the president of Harvard University and a senior scientific adviser to the US government, got to read it. Finally, in October 1941, he and other scientists persuaded President Roosevelt to commit the US government to developing and building an atomic bomb. Roosevelt offered to include the British in this effort but Churchill refused, believing that his scientists were ahead of their American counterparts (at this point, they were). However, once the United States came into the war after Pearl Harbor in December 1941, the Americans’ work on their atom bomb went up a gear and rapidly pulled ahead of anything going on in Britain. In September 1942, General Leslie Groves was put in charge of the project, which now came under the supervision of the US Army. Three months later, the first nuclear reactor was built in Chicago. But the work involved in making a bomb proved far more complex than anything imagined by Thomson and his team in Britain. The Manhattan Project, as the US research came to be known, developed into one of the biggest scientific operations of all time, employing 120,000 people across 37 different research sites. Robert Oppenheimer led the scientific work and finally, four years after the Maud Report had been produced, in July 1945, an experimental bomb was successfully tested in Alamogordo, New Mexico. One of the scientists present at this test, code-named ‘Trinity’, wrote:

Suddenly there was an enormous flash of light, the brightest light that I have ever seen or that I think anyone has ever seen … as we looked toward the place where the bomb had been, there was an enormous ball of fire which grew and grew, and it rolled as it grew … A new thing had just been born; a new control; a new understanding of man, which man had acquired over nature.³⁰

The war against Germany had already been won two months earlier. The war against Japan would be over within a month.

The atomic bomb had a strange lineage: from Germany to Britain, then through Tizard, Thomson and Cherwell to Churchill, and from him to the United States and into the full Manhattan Project. Only America had the vast resources needed for the development of a weapon that would transform world politics and the balance of power for the next fifty years. But Britain’s War Lab had played a key role in starting the ball rolling. For good or ill, the partnership between scientists and soldiers had helped to produce the most destructive weapon known to mankind.