The Codebreakers: The True Story of the Secret Intelligence Team That Changed the Course of the First World War (23 page)

Field set trench telephone

The Moritz sets fed on a rich diet provided by the careless and sloppy use of telephones by the British – though the French weren’t much better. As neither had developed equivalent technology yet, they operated in blissful ignorance of the German capability, nattering away
en clair
, or when using code, using it badly.

In the major offensives launched by the Allies, the elusive goal was ‘breakthrough’ – getting beyond the ranks of German defensive lines and into open country – where the cavalry, not yet abandoned as a potentially decisive weapon, could run riot. To achieve this, the first days of battle, before the enemy could rally, pour in extra troops and launch counterattacks, were critical. Surprise was essential. However, the Moritz sets meant that the Germans were forewarned and forearmed. Their defensive capability gained immeasurably from insights into who was facing them, in what numbers and where. The exact locations of the series of assaults launched by the French during 1915 were known well in advance.

Major R. E. Priestley, author of the Royal Engineers history of the Signal service, wrote that ‘the question of enemy overhearing had arisen in the summer of 1915’. A disturbing pattern was emerging: carefully planned raids and minor attacks were ‘met with hostile fire, exactly directed and timed to the minute’. This was happening too often to be mere coincidence. All the indications suggested that the leakage of information was ‘intimately connected to the extension of telephone to the front-line trenches’.

However, the warning signs were ignored. In his diary entry for 4 April 1915, Brigadier General John Charteris, Haig’s intelligence supremo, the man responsible for keeping the Commander in Chief of British forces up to speed, noted in his diary a conversation he had with the commander of the 9th Battalion Highland Light Infantry (Glasgow Highlanders), who thought the enemy had ‘very good information on our front-line dispositions’ based on the fact that when his men approached the German trenches they were greeted by ‘a good imitation of a Glasgow tram conductor’s voice’ and a gramophone playing ‘Stop Your Tickling Jock’.

Though Charteris found this amusing, he also saw the serious side: clearly the Germans had some source of information, most likely captured British soldiers. It did not even occur to him that there might be another explanation or that the incident was alarming enough to merit further investigation. This failure to join the dots was to have even more serious consequences – so serious that they finally alerted GHQ to the problem – during the Battle of the Somme.

The British army was not meant to lead a major offensive in 1916; that dubious honour had fallen to the French. The massive German onslaught on Verdun, designed to bleed the French army to death, necessitated a change in plan. The onus was now on the British to take the initiative. Haig pondered his options and settled on the Somme. This five-month campaign, the biggest battle of the war so far, would consume hundreds of thousands of lives for the gain of a few miles; it has become synonymous with everything mind-numbingly awful about the Western Front. Had telephone security been better, things might have turned out differently.

The British plan relied on achieving major gains within 24 hours of the infantry going over the top. Intelligence derived from Moritz gave the Germans a clear picture of what to expect; what they couldn’t discover was when the assault would come and when the immense, relentless artillery barrage that preceded it would end. Day after day they prayed for the guns to fall silent as hell rained down on them.

A few hours before dawn on 1 July, as the Tommies readied themselves in their forward trenches, the Germans were gifted the information they needed: a Moritz station intercepted a message from British HQ offering encouragement to the troops waiting to advance. Any possibility that the Germans would be taken by surprise was gone, and with it the chance of a decisive outcome.

The first day on the Somme was a disaster as yet unparalleled in the history of the British army. Reflecting on the reasons for this unholy mess, commanders finally woke up to the problem of loose talk. A memo issued by the General Staff on 23 July noted that there was clear evidence that a ‘German system of overhearing’ was being extensively used, and that ‘it must be assumed that the enemy has listening apparatus’.

Incontrovertible proof that these suspicions were well founded came during July, when the German stronghold at Ovillers-la-Boisselle was captured after numerous costly attacks. The occupying troops discovered that the Germans had left behind a complete copy of the operational orders of the British corps that had repeatedly tried to storm the position.

Stringent efforts were made to enforce greater discipline. A lengthy memo appeared in October on ‘The Indiscreet Use of Telephones’. It demanded an end to unnecessary gossip, and the introduction of silent hours, and warned that any disobedience of those orders would be severely punished. It was too little, too late. The Moritz sets were still able to identify 70 per cent of the British units deployed over the course of the battle, knowledge that was used to devastating effect.

One of the most revealing accounts of life as an intelligence officer on the Western Front was written by Ferdinand Tuohy, a journalist who’d worked for the Northcliffe press. In it he constantly drew attention to the lack of imagination displayed by his superiors and their tendency to be reactive rather than proactive. That he was eventually to pioneer a wireless interception and codebreaking system that would help the British learn something useful from the Somme campaign is testament to his persistence and his refusal to play by the rules.

Tuohy began the war reporting for
The Times
and covered the First Battle of Ypres. In January 1915 he was sent to Poland to investigate the situation there; stuck in Warsaw, and unable to get to the front, he ‘had no option but to continue writing the stereotypical stuff’ about ‘fearless and faithful Ivan’, though in reality he found the Russians ‘boorish and primitive’. Nevertheless, he pitied the peasant conscripts who formed the majority of the army; they were ‘massacred like mutton’, had no leave, no pay and no mail and, due to 80 per cent illiteracy, were ‘unable even to break, by reading or writing, the desperate boredom of trench life’.

Eventually Tuohy got amongst the action, finding himself at the Second Battle of Bzura, fought along a 30-mile front that was ‘bleak, freezing, desperate’. Signing on with an ambulance unit, he then moved on to the great Austro-Hungarian fortress Przemyśl, which guarded the gateway into the Carpathian Mountains and had fallen to the Russians in March 1915 after a bitter siege. He witnessed scenes of appalling devastation, ‘ruined, diseased and starving villages all around’. By the end of May, the citadel was back in enemy hands and Tuohy was back in England recounting what he’d seen to a shocked Northcliffe, who was appalled that ‘we know practically nothing of all this … and I don’t believe the cabinet does either’.

Decent information about what was actually happening on the Eastern Front, where vast armies ranged over hundreds and hundreds of square miles, retreating one minute, advancing the next, was extremely difficult to come by, with even commanders on the ground finding it hard to keep track of the fighting. So Northcliffe dispatched Tuohy to the Foreign Office to fill them in. They directed him to the War Office, where he was asked to join the Intelligence Corps. After a few months studying maps and being taught about the German army, he was sent to Ypres.

Without listening sets of their own, officers like Tuohy were obliged to crawl up to the German lines under cover of darkness to try and overhear enemy chat. This rudimentary approach finally ended after the French developed a listening set comparable to the Moritz, which the British called ITOC. It could pick up German conversation some 500 yards from the front line. The sets were located in a dugout with wires leading out of it into no-man’s-land and operated by two interceptors, young men of ‘the clerical breed, experts in dialectical German … with telephone headpieces glued to their ears … pencil in hand’ ready to jot down any stray snatches of conversation. Tuohy would sift through the results, picking out from the ‘voluminous twaddle’ any useful titbits relating to matters of tactical concern.

The fact was, German telephone procedures, established early and based on the belief that if they had listening devices then so must the Allies, were far more secure. Special codes, consisting of simple word substitutions, were introduced to reduce the risks of interception: ‘snake’ for ‘casualty’, ‘monkey’ for ‘prisoner’, ‘carp’ for ‘Frenchman’, ‘dried cod’ for ‘British soldier’, ‘walrus’ for ‘Russian’, etc., giving rise to sentences like ‘we had some snakes, but brought in several monkeys including a walrus, a carp and a dried cod’.

Tuohy realised that ‘the enemy was obviously getting more vital results from Moritz than we had ever got from ITOC’. Where the ITOC sets came into their own was as ‘an instrument for policing the conversations of our own men’. What they revealed was that old habits died hard: too much pertinent information was still being bantered about. Over the course of one month, a single set heard 40 units referred to by name and talk relating to the movement of troops, operation orders and positions behind the line.

At least now there was a way to keep track of the leaks, much to the resentment of the men, who felt spied on by their own side. The result was that ‘in due course a distinct hush fell over our front trench system’. This hush spread to the German lines, and by the end of 1917 there was precious little for the listening sets to overhear. By then Tuohy had played a vital part in establishing an interception system that for once was ahead of the Germans.

While the daring, blind courage and glamour of the ace fighter pilots engaged in aerial combat grabbed the headlines, the real tactical value of the air force came from reconnaissance. Aside from the quantum leaps in photographic technology that produced ever more detailed images of the battle zones, wireless was employed by the spotter planes to register targets for the artillery and monitor events on the ground.

In early 1915, the Royal Flying Corps, working in tandem with the Marconi Experimental Laboratory in Surrey, developed a lightweight transmitting set with a range of 20 miles. Pilots were taught by Marconi engineers how to operate it, and by 1918 this primitive radio was installed in 600 planes. Messages from the pilots to the ground were encoded using a clock-face system, with different segments relating to particular map references. Armed with this technology, flying low over the German lines, these planes greatly improved the accuracy and tactical efficiency of the artillery: counter-battery fire – shelling the enemy’s guns – relied almost exclusively on information coming from the air.

The Germans had wireless in their planes too, and the British were soon intercepting messages sent by them. However, analysis of this material progressed slowly until Tuohy got involved. He described how, in the late summer of 1915, ‘a wireless set with a battery near the ramparts of Ypres’ was picking up the call sign of the enemy spotters, ‘a high pitched, quivering note’, as they communicated the position of British troops to their artillery. Tuohy quickly understood that if you could ‘connect given German wireless call sign with known … hostile batteries’, the British guns could then turn their sights on the German artillery that had been identified by the planes’ wireless signals ‘and crump its personnel back into the bowels of the earth’. Equally, the position of the German spotter planes could be tracked, leaving them vulnerable to the attentions of the British fighter squadrons.

Armed with a mass of material, Tuohy attempted to break the codes used by the German planes. Sitting up all night ‘bent over fragmentary wireless hieroglyphics’, he laboured for months ‘trying every conceivable juggling of lettering based on German colloquialisms’ until, after much guesswork and deduction, he solved their letter code. A parallel numerical code continued to defy him until a downed plane was recovered with its wireless set and code book intact.

By early 1916, the British army had what it needed to gain a real advantage. But it failed to act: ‘GHQ got everything we had, yet we got little in return.’ Tuohy put the unforgivable delay down to the intractability of the system: ‘minds were warped by a departmental outlook’ and ‘mountainous documentary files came into being in which the vital end to be achieved was lost, submerged’. Meanwhile, ‘British soldiers were dying in thousands as a direct result’.

Six months later, and only because the desperate situation on the Somme demanded it, this system of analysing messages sent by German planes was finally given its due. Every evening Tuohy briefed General Hugh Trenchard, head of the RFC, on the aeroplane wireless activity of that day.

The impact of these measures was felt immediately by the German army. As the number of prisoners and abandoned dead and wounded mounted, so did the volume of letters, diaries and documents acquired by British intelligence. A common theme was the ever-present threat posed by the RFC. One soldier complained that ‘the English are always flying over our lines, directing artillery fire, consequently getting all their shells … right into our trenches’. Another noted in his diary that ‘once a battery has been located it can result in it attracting 2,000–3,000 shells’, while an officer admitted that ‘whenever the slightest movement was visible in our trenches … a heavy bombardment of that section took place’.

By the time Tuohy left France for pastures new, he was delighted to see ‘a network of 14 wireless intelligence posts established’. By the end of the war there were a thousand, manned by 18,000 staff. Between October 1916 and March 1917, they successfully decoded messages from more than two-thirds of the flights made by enemy spotter planes. During that year, 50–60 per cent of the Germans’ infantry divisions and artillery formations were pinpointed thanks to the methods advanced by Tuohy.

Yet despite all the effort and innovation, coupled with the undoubted improvements that wireless intelligence brought with it, victory remained an ever-receding prospect. The blood of nations was draining into the mud, yet the staggering casualties suffered by all sides did not appear to be bringing the end any nearer.