Authors: Brian Ford
Tags: #Secret Weapons: Death Rays, #Doodlebugs and Churchill’s Golden Goose
Ultra was the code name for the British decryption project and it was at Bletchley Park that the Ultra project was based. The teams monitored, and successfully decoded, the messages sent from Germany to the U-boats during the battle of the Atlantic. The Bletchley teams also decoded all the orders sent out in the North Africa campaign in 1941, and General Auchinleck later confessed that ‘Rommel would have certainly got through to Cairo’ without the Allies having advance knowledge of all the German plans. During the planning of the Allied invasion of Normandy, Bletchley Park gave the Allied commanders full details of all but two of the 58 Nazi divisions situated on the Western Front. The United States were kept fully involved, and Americans had been invited to become part of the Bletchley Park teams from the start; but Churchill did not trust the Soviet authorities and they never knew of Bletchley Park for the duration of the war. Eventually, the term ‘Ultra’ was adopted by all the Western Allies to signify the decoding of German messages.
When we arrived at Bletchley station we were met by a leading Wren and marched up to a perimeter fence with sentries standing guard. We were then taken to an office in a grand Victorian mansion where we were told that the work we were going to be doing was of the utmost secrecy and vital to the war effort, and we were required to sign the official secrets act. One was left with the distinct impression that contravening it would mean a spell in the Tower at the very least. Next we were escorted across the large grounds to a concrete hut, and had to press a bell and wait to be admitted. When we went inside I was immediately aware of the large back machines making a terrible din and smelling of hot oil. These were the bombes, which were essential to the breaking of the German Enigma codes…
Work in the bombe hut went on 24 hours a day and we worked 8 hour watches with one meal break. The first week was from 8 am to 4 pm, the second 4 pm to midnight and the third midnight to 8 am, with one day off each week. On the fourth week we worked everybody else’s days off and then had 4 days leave. There were two Wrens to each machine and our job was to change the wheel orders, which has a different colour for each number, in accordance with the list given by the code-breakers in Huts 6 and 8. They also dictated how the alphabetised sockets on the back of the machine should be connected to each other. The piece of paper given to us for this purpose was called, interestingly, a menu – the same word we have for starting points on our computers today. Once all this had been done the machine was started up and it clanked and whirred and eventually it would stop. We noticed the wheel order running at that time and the position at which it had stopped and phoned it through to Hut 6 and 8. This could go for hours or even days, with several machines working on the same job, but eventually the cry would be heard: ‘Job up’, which meant they had a match. Occasionally the job didn’t come up and was abandoned because the next day’s settings would now be in operation.
It was quite physical work, plugging and unplugging the menu, working as fast as we could to change the wheel orders and, most importantly, checking the drums when we took them off the machine. The underside of each drum had four circular rows of small wire brushes which had to be kept in a state of perfection. A stray wire could cause a short and distort all the information gathered by the machine, so we had to straighten them with wire tweezers. I don’t think all that close work did our eyesight much good and the noise in Hut 11 properly affected our hearing, too.
Anne Chetwynd-Stapylton, courtesy of Bletchley Park.
There was just one major scare, when three bombs were dropped by a German aircraft in November 1940, just as the base was coming fully on stream. It turned out to be an error, for the bombs had actually been intended for the nearby rail station at Bletchley. The only effect was that one of the bombs blasted Hut 4, housing the Royal Navy Intelligence Unit, off its brick-built base. Workers simply jacked it up, back into position, and work went on as though nothing had happened. Those who worked at Bletchley Park took their task seriously, and never spoke of it afterwards. Even by the 1990s little had ever been disclosed. Churchill noted the unimpeachable level of personal security when, at the end of the war, he described Bletchley Park as ‘The Golden Goose that never cackled’.
By the end of the war, with the code-breaking at its absolute height, there were over 9,000 people employed at Bletchley Park. Of those, 80 per cent were women and most of the men were postal delivery workers, specialists in high-speed Morse code or linguists who could translate German rapidly. The code-breakers were selected at interview if they were, for example, champions at playing chess or finishing crossword puzzles; some were multilingual, others were top mathematicians. At one time, a test involved the ability to solve the
Daily Telegraph
crossword in less than 12 minutes. The winner of the competition was F. H. W. Hawes of Dagenham, East London, who finished the entire puzzle in 7 minutes.
Ultra was certainly vital to the winning of the war. Although the Enigma machines were their best-known target, they also successfully decoded messages from other encryption machines, including the Lorenz SZ series (
Schlüsselzusatz
, ‘cipher attachment’) and various systems adopted by the Japanese. Churchill is said to have told King George VI, ‘It was thanks to Ultra that we won the war.’ Western Supreme Allied Commander, Dwight D. Eisenhower, insisted that Ultra was ‘decisive’ in securing the Allied victory. It has often been said that Ultra advanced the winning of the war by two years; others have emphasized that, without it, the war might not have been won by the Allies at all.
Though there is clearly truth in all this, there are others whose work is equally deserving of commemoration. What of the heroic Poles, whose brilliance gave us the Bombe machines without which the battle of the codes could easily have been lost? The role of the American teams and their Bombe machines is often overlooked – yet, by the end of the war, well over 100 high-specification Bombes had been manufactured in the United States and their teams worked tirelessly to decode the incessant German military messages. The Americans were hugely successful in this vital field.
Alan Turing was crucial to this effort, yet he was to end his days in misery. As a gay man (at a time when homosexuality in a man was a crime) he was to become ostracized and persecuted rather than praised. In 1952 he was found guilty of acts of gross indecency and was threatened with gaol. He opted to be injected with large doses of female hormones that were claimed to reduce his urges, and this ‘chemical castration’ was agreed by the court as an alternative to imprisonment. But his career was effectively destroyed; he lost his security clearance and his government position. Turing retreated into himself and became distressed. Within two years he was found dead in bed from cyanide poisoning. He had often said how much he liked the Walt Disney film
Snow White
, particularly the scene where the Wicked Witch poisons a red apple … and a half-eaten apple was found on his bedside cabinet. Had it been used to deliver the fatal dose? We cannot know; the apple was never tested by the police.
So much of what we accept as today’s truth is a distortion of reality. It is almost as though these most secret of schemes have acquired a new reality all of their own. The Enigma machine was not a secret device that was known only to a few. Over 100,000 Enigma machines were manufactured, and they were widely sold all over the world. It is an astonishing total. These encoding machines remained in use long after the end of World War II. Thousands were captured, intact, by the Allies as they advanced across Germany. And what was their fate? They were sold, in large numbers, to the governments of many of the newly emergent nations. So ingenious was the German design that Enigma continued to be used in peacetime for many years after the end of World War II. None of the purchasers knew anything of the code-breakers of Bletchley Park, so they were none the wiser; and Enigma lived on for a decade or more.
The first design for a computer was, of course, a mechanical device with gears and levers designed by the British mathematician Charles Babbage. He first wrote down the idea in a letter to Sir Humphrey Davy in 1822. His design could not be manufactured at the time (machining tolerances were not sufficiently advanced) but in 1991 a version was manufactured and was shown to work at the Science Museum, London. Babbage envisaged using a mechanical computer to calculate the odds on a horse race, since he was an inveterate gambler.
The first person actually to construct an electromechanical computer was a German aircraft technician and amateur enthusiast, Konrad Zuse. He used punched paper tape to input data and developed the first programming language, Plankalkül (plan calculus). His first machine, the Z1, was able to use binary floating point numbers, which allows for large calculations, and a form of programming based on the work on the Victorian English mathematician George Boole. Boole derived the form of analysis that combines terms (using ‘and’) or splits them into alternatives (‘or’) and Boolean logic, as we now call it, is essential in writing software. This early computer had no relays and a single electrical unit to give a clock speed of 1Hz. The Z1 could be programmed using punched tape and a tape reader. Zuse built it with his own (and his family’s) money between 1936 and 1938, using part of the family living-room as his laboratory. This pioneering computer embodied most of the components we would recognize in a present-day machine, including a control unit and simple computer memory. He went on later to construct more advanced prototypes and hoped to make them commercially available. However, although he made several attempts to interest the German military in the possibilities offered by his computer, no-one there was interested. All his machines, and the documentation, were destroyed during the Allied bombing raids on Berlin in December 1943.
The first programmable electronic computer was named Colossus, and was produced specifically to crack the Lorenz codes used by the German High Command, since these codes were more complex than those generated by Enigma. Colossus was designed and built by a team led by Harold Thomas Flowers who began working on the idea in the late 1930s. As a young engineer, Tommy Flowers had the idea of using thermionic radio valves, or vacuum tubes, as programmable switches. He fed data in using punched tape, like a ticker-tape machine. His original idea was to automate the British telephone exchanges, but as the war took hold news reached him of the need to decode German messages that were being intercepted by the intelligence service as part of the Ultra project. Tommy Flowers began work in 1941 and took just six months to demonstrate a prototype machine, and – unlike Zuse – he found the British authorities were becoming interested in what his computer could do.
In February 1943 construction work on the revolutionary computer began at the Post Office Research Station in Dollis Hill, North-West London. The computer was running successfully by December that same year, so it was disassembled and driven to Bletchley Park on 18 January 1944. It was fitted together again and worked perfectly, and was given its first message to decode on 5 February 1944. This Mark 1 Colossus was such a success that a further nine of the giant computers were ordered. The design and specifications were improved, and in June 1944 the Mark 2 went into full production. Colossus Mark 1 contained an astonishing 1,500 electronic tubes developed for radios, whilst the Mark 2 was fitted with 2,400 of these valves making it both simpler to use and five times faster. These Colossus computers could process nearly 10,000 characters per second, but the paper tape soon became shredded. The punched paper tape could pass safely through the readers at a maximum speed of 27.3mph (12.2m/s) so they settled on 5,000 characters per second as the optimum rate of operation. Trials were also held where two Colossus computers were used simultaneously on the same problem, thus proving the value of parallel computing.
It was the use of the Colossus machines by the War Department in London that allowed the British to considerably reduce the ability of German Admiral Karl Dönitz to make unexpected raids upon the convoys crossing the North Atlantic, and thousands of lives must have been saved. These Allied victories turned the course of the war.
The Americans stationed at Bletchley Park were highly impressed, and encouraged John Mauchly and J. Presper Eckert to press ahead with the design of a more advanced version at the Moore School of Electrical Engineering of the University of Pennsylvania. Their design and development was code named Project
PX
and their prototype machine, ENIAC, was unveiled after World War II was over, on 14 February 1946. It had cost some $500,000 to build, worth $6 million today, a huge sum of money for such a project. This state-of-the-art computer was intended to make artillery calculations, but was soon being utilized for work on the development of the first hydrogen bomb.
Meanwhile, in Britain, even the very existence of Colossus was covered by the Official Secrets Act and it all remained a state secret well into the 1970s. The British authorities have always been sensitive about classified information, and the staff at Bletchley Park refused to talk about their work even into the 1990s. Although all of the ten Colossus computers survived into the 1980s, they were broken up and their records destroyed. The teams remained silent.
The historical importance of the early Zuse computers became increasingly apparent in the post-war years, and in 1986 Konrad Zuse resolved to rebuild his original Z1 computer. It remains an important historical device for it embodies all the essential components we recognize in present-day computers. The task took him three years, and it was shipped to the Deutsches Technik Museum in Berlin-Kreuzberg where it is on display, in full working order, to this day.