Enigma
Page 4
TOMORROW AT 1700 BE IN NEW PATROL LINE FROM NAVAL GRID SQUARE AK2564 TO 2994. OPERATIONS AGAINST EASTBOUND CONVOY WHICH AT 1200/7/12 WAS IN NAVAL GRID SQUARE AK4189. COURSE 050 TO 070 DEGREES. SPEED APPROX 8 KNOTS.
By midnight they had broken, translated and teleprintered to London ninety-two Shark signals giving the Admiralty the approximate whereabouts and tactics of half the Germans’ U-boat fleet.
Jericho was in the Bombe Hut when Logie found him. He had been chasing about for the best part of nine hours and now he was supervising a changeover on one of the machines, still wearing his pyjamas under his overcoat, to the great amusement of the Wrens who tended the bombe. Logie clasped Jericho’s hand in both of his and shook it vigorously.
‘The Prime Minister!’ he shouted in Jericho’s ear, above the clattering of the bombes.
‘What?’
‘The Prime Minister has just been on the telephone with his congratulations!’
Logie’s voice seemed a long way away. Jericho bent forward to hear better what Churchill had said and then the concrete floor melted beneath his feet and he was pitching forward into darkness.
‘Is,’ said Jericho.
‘What, old thing?’
‘Just now, you said Shark was a monster and then you said it is a monster.’ He pointed the fork at Logie. ‘I know why you’ve come. You’ve lost it, haven’t you?’
Logie grunted and stared into the fire and Jericho felt as though someone had laid a stone on his heart. He sat back in his chair, shaking his head, then gave a snort of laughter.
‘Thank you, Tom,’ said Logie, quietly. ‘I’m glad you find it funny.’
‘And all the time I thought you’d come here to give me the push. That’s funny. That’s pretty funny, isn’t it, old thing?’
‘What day is it today?’ asked Logie.
‘Friday.’
‘Right, right.’ Logie extinguished his pipe with his thumb and stuffed it into his pocket. He sighed. ‘Let me see. That means it must have happened on Monday. No, Tuesday. Sorry. We haven’t had a lot of sleep lately.’
He passed a hand through his thinning hair and Jericho noticed for the first time that he’d turned quite grey. So it’s not just me, he thought, it’s all of us, we’re all falling to pieces. No fresh air. No sleep. Not enough fresh food. Six-day weeks and twelve-hour days …
‘We were still just about ahead of the game when you left,’ said Logie. ‘You know the drill. Of course you do. You wrote the bloody book. We’d wait for Hut 10 to break the main naval weather cipher, then, by lunchtime, with a bit of luck we’d have enough cribs to tackle the day’s short weather codes. That would give us three of the four rotor settings and then we’d get stuck into Shark. The time-lag varied. Sometimes we’d break it in one day, sometimes three or four. Anyway, the stuff was gold-dust and we were Whitehall’s blue-eyed boys.’
‘Until Tuesday.’
‘Until Tuesday.’ Logie glanced at the door and dropped his voice. ‘It’s an absolute tragedy, Tom. We’d cut losses in the North Atlantic by 75 per cent. That’s about three hundred thousand tons of shipping a month. The intelligence was amazing. We knew where the U-boats were almost as precisely as the Germans did. Of course, looking back, it was too good to last. The Nazis aren’t fools. I always said: “Success in this game breeds failure, and the bigger the success, the bigger the failure’s likely to be.” You’ll remember me saying it. The other side gets suspicious, you see. I said –’
‘What happened on Tuesday, Guy?’
‘Right-ho. Sorry. Tuesday. It was about eight in the evening. We got a call from one of the intercept stations. Flowerdown, I think, but Scarborough heard it too. I was in the canteen. Puck came and fetched me out. They’d started picking up something in the early afternoon. A single word, broadcast on the hour, every hour. It was coming out of Sainte-Assise on both main U-boat radio nets.’
‘This word was enciphered in Shark, I take it?’
‘No, that’s just it. That’s what they were so excited about. It wasn’t in cipher. It wasn’t even in Morse. It was a human voice. A man. Repeating this one word: Akelei.’
‘Akelei,’ murmured Jericho. ‘Akelei … That’s a flower, isn’t it?’
‘Ha!’ Logie clapped his hands. ‘You are a bloody marvel, Tom. See how much we miss you? We had to go and ask one of the German swots on Z-watch what it meant. Akelei: a five-petalled flower of the buttercup family, from the Latin Aquilegia. We vulgarians call it columbine.’
‘Akelei,’ repeated Jericho. ‘This is a prearranged signal of some sort, presumably?’
‘It is.’
‘And it means?’
‘It means trouble, is what it means, old love. We found out just how much trouble at midnight yesterday.’ Logie leaned forwards. The humour had left his voice. His face was lined and grave. ‘Akelei means: “Change the Short Weather Code Book.” They’ve gone over to a new one and we haven’t a bloody clue what to do about it. They’ve closed off our way into Shark, Tom. They’ve blacked us out again.’
It didn’t take Jericho long to pack. He’d bought nothing since he arrived in Cambridge except a daily newspaper, so he took out exactly what he’d carried in three weeks earlier: a pair of suitcases filled with clothes, a few books, a fountain pen, a slide rule and pencils, a portable chess set and a pair of walking boots. He laid his cases on the bed and moved slowly about the room collecting his possessions while Logie watched him from the doorway.
Running round and round in his head, unbidden from some hidden depth in his subconscious, was a nursery rhyme: ‘For want of a nail, the horse was lost; for want of a horse, the rider was lost; for want of a rider, the battle was lost; for want of a battle, the kingdom was lost; and all for the want of a horseshoe nail …’
He folded a shirt and laid it on top of his books.
For want of a Short Weather Code Book they might lose the Battle of the Atlantic. So many men, so much material, threatened by so small a thing as a change in weather codes. It was absurd.
‘You can always tell a boarding-school boy,’ said Logie, ‘they travel light. All those endless train journeys, I suppose.’
‘I prefer it.’
He stuffed a pair of socks down the side of the case. He was going back. They wanted him back. He couldn’t decide whether he was elated or terrified.
‘You don’t have much stuff in Bletchley, either, do you?’
Jericho swung round to look at him. ‘How do you know that?’
‘Ah.’ Logie winced with embarrassment. ‘I’m afraid we had to pack up your room, and, ah, give it to someone else. Pressure of space and all that.’
‘You didn’t think I’d be coming back?’
‘Well, let’s say we didn’t know we’d need you back so soon. Anyway, there’s fresh digs for you in town, so at least it’ll be more convenient. No more long cycle rides late at night.’
‘I rather like long cycle rides late at night. They clear the mind.’ Jericho closed the lids on the suitcases and snapped the locks.
‘I say, you are up to this, old love? Nobody wants to force you into anything.’
‘I’m a damn sight fitter than you are, by the look of you.’
‘Only I’d hate you to feel pressured …’
‘Oh do shut up, Guy.’
‘Right-ho. I suppose we haven’t left you with much choice, have we? Can I help you with those?’
‘If I’m well enough to go back to Bletchley, I’m well enough to manage a couple of suitcases.’
He carried them to the door and turned off the light. In the sitting room he extinguished the gas fire and took a last look around. The overstuffed sofa. The scratched chairs. The bare mantelpiece. This was his life, he thought, a succession of cheaply furnished rooms provided by English institutions: school, college, government. He wondered what the next room would be like. Logie opened the doors and Jericho turned off the desk light.
The staircase was in darkness. The bulb had long since died. Logie
got them down the stone steps by striking a series of matches. At the bottom, they could just make out the shape of Leveret, standing guard, his silhouette framed against the black mass of the chapel. He turned round. His hand went to his pocket.
‘All right, Mr Leveret,’ said Logie. ‘It’s only me. Mr Jericho’s coming with us.’
Leveret had a blackout torch, a cheap thing swathed in tissue paper. By its pale beam, and by the faint residue of light still left in the sky, they made their way through the college. As they walked alongside the Hall they could hear the clatter of cutlery and the sound of the diners’ voices, and Jericho felt a pang of regret. They passed the Porter’s Lodge and stepped through the man-sized gate cut in the big oak door. A crack of light appeared in one of the lodge’s windows as someone inside pulled back the curtain a fraction. With Leveret in front of him and Logie behind, Jericho had a curious sensation of being under arrest.
The deputy director’s Rover was pulled up on the cobbled pavement. Leveret carefully unlocked it and ushered them into the back seat. The interior was cold and smelled of old leather and cigarette ash. As Leveret was stowing the suitcases in the boot Logie said suddenly: ‘Who’s Claire, by the way?’
‘Claire?’ Jericho heard his voice in the darkness, guilty and defensive.
‘When you came up the staircase I thought I heard you shouting “Claire”. Claire?’ Logie gave a low whistle. ‘I say, she’s not the arctic blonde in Hut 3, is she? I bet she is. You lucky bugger …’
Leveret started the engine. It stuttered and backfired. He let out the brake and the big car rocked over the cobbles on to King’s Parade. The long street was deserted in both directions. A wisp of mist shone in the shaded headlamps. Logie was still chuckling to himself as they swung left.
‘I bet she jolly well is. You lucky, lucky bugger …’
Kite stayed at his post by the window, watching the red tail-lights until they vanished past the corner of Gonville and Caius. He let the curtain drop.
Well, well …
This would give them something to talk about the next morning. Listen to this, Dottie. Mr Jericho was taken away at dead of night – oh, all right then, eight o’clock – by two men, one a tall fellow and the other very obviously a plain clothes copper. Escorted from the premises and not a word to anyone. The tall chap and the copper had arrived about five o’clock while the young master was still out walking and the big one – the detective, presumably – had asked Kite all sorts of questions: ‘Has he seen anyone since he’s been here? Has he written to anyone? Has anyone written to him? What’s he been doing?’ Then they’d taken his keys and searched Jericho’s room before Jericho got back.
It was murky. Very murky.
A spy, a genius, a broken heart – and now what? A criminal of some sort? Quite possibly. A malingerer? A runaway? A deserter! Yes, that was it: a deserter!
Kite went back to his seat by the stove and opened his evening paper.
NAZI SUB TORPEDOES PASSENGER LINER, he read. WOMEN AND CHILDREN LOST.
Kite shook his head at the wickedness of the world. It was disgusting, a young man of that age, not wearing uniform, hiding away in the middle of England while mothers and kiddies were being killed.
TWO
CRYPTOGRAM
CRYPTOGRAM: message written in cipher or in some other secret form which requires a key qy for its meaning to be discovered.
A Lexicon of Cryptography
(‘Most Secret’, Bletchley Park, 1943)
1
THE NIGHT WAS impenetrable, the cold irresistible. Huddled in his overcoat inside the icy Rover, Tom Jericho could barely see the flickering of his breath or the mist it formed on the window beside him. He reached across and rubbed a porthole in the condensation, smearing his fingers with cold, wet grime. Occasionally their headlamps flashed on whitewashed cottages and darkened inns, and once they passed a convoy of lorries heading in the opposite direction. But mostly they seemed to travel in a void. There were no street lights or signposts to guide them, no lit windows; not even a match glimmered in the blackness. They might have been the last three people alive.
Logie had started to snore within fifteen minutes of leaving King’s, his head dropping further forwards onto his chest each time the Rover hit a bump, a motion which caused him to mumble and nod, as if in profound agreement with himself. Once, when they turned a corner sharply, his long body toppled sideways and Jericho had to fend him off gently with his forearm.
In the front seat Leveret hadn’t uttered a word, except to say, when Jericho asked him to turn it on, that the heater was broken. He was driving with exaggerated care, his face hunched inches from the windscreen, his right foot alternating cautiously between the brake pedal and the accelerator. At times they seemed to be travelling scarcely faster than walking-pace, so that although in daylight the journey to Bletchley might take little more than an hour and a half, Jericho calculated that tonight they would be lucky to reach their destination before midnight.
‘I should get some sleep if I were you, old thing,’ Logie had said, making a pillow of his overcoat. ‘Long night ahead.’
But Jericho couldn’t sleep. He stuffed his hands deep into his pockets and stared uselessly into the night.
Bletchley, he thought with disgust. Even the sensation of the name in the mouth was unpleasant, stranded somewhere between blanching and retching. Of all the towns in England, why did they have to choose Bletchley? Four years ago he’d never even heard of the place. And he might have lived the rest of his life in happy ignorance had it not been for that glass of sherry in Atwood’s rooms in the spring of 1939.
How odd it was, how absurd to trace one’s destiny and to find that it revolved around a couple of fluid ounces of pale manzanilla.
It was immediately after that first approach that Atwood had arranged for him to meet some ‘friends’ in London. Thereafter, every Friday morning for four months, Jericho would catch an early train and make his way to a dusty office block near St James’s tube station. Here, in a shabby room furnished by a blackboard and a clerk’s desk, he was initiated into the secrets of cryptography. And it was just as Turing had predicted: he loved it.
He loved the history, all of it, from the ancient runic systems and the Irish codes of the Book of Ballymote with their exotic names (‘Serpent through the heather’, ‘Vexation of a poet’s heart’), through the codes of Pope Sylvester II and Hildegard von Bingen, through the invention of Alberti’s cipher disk – the first poly-alphabetic cipher – and Cardinal Richelieu’s grilles, all the way down to the machine-generated mysteries of the German Enigma, which were gloomily held to be unbreakable.
And he loved the secret vocabulary of cryptanalysis, with its homophones and polyphones, its digraphs and bigraphs and nulls. He studied frequency analysis. He was taught the intricacies of superencipherment, of placode and enicode. At the beginning of August 1939 he was formally offered a post at the Government Code and Cipher School at a salary of three hundred pounds a year and was told to go back to Cambridge and await developments. On 1 September he woke to hear on the wireless that the Germans had invaded Poland. On 3 September, the day Britain declared war, a telegram arrived at the Porter’s Lodge ordering him to report the following morning to a place called Bletchley Park.
He left King’s as instructed, as soon as it was light, wedged into the passenger seat of Atwood’s antiquated sports car. Bletchley turned out to be a small Victorian railway town about fifty miles west of Cambridge. Atwood, who liked to cut a dash, insisted on driving with the roof off, and as they rattled down the narrow streets Jericho had an impression of smoke and soot, of little, ugly terraced houses and the tall, black chimneys of brick kilns. They passed under a railway bridge, along a lane, and were waved through a pair of high gates by armed sentries. To their right, a lawn sloped down to a lake fringed by large trees. To their left was a mansion – a long, low, late-Victorian monstrosity of red brick and sand-coloured stone that reminded Jericho of the veteran
s’ hospital his father had died in. He looked around, half expecting to see wimpled nurses wheeling broken men in Bath chairs.
‘Isn’t it perfectly hideous?’ squeaked Atwood with delight. ‘Built by a Jew. A stockbroker. A friend of Lloyd George.’ His voice rose with each statement, suggesting an ascending scale of social horror. He parked abruptly at a crazy angle, with a spurt of gravel, narrowly missing a sapper unrolling a large drum of electrical cable.
Inside, in a panelled drawing room overlooking the lake, sixteen men stood around drinking coffee. Jericho was surprised at how many he recognised. They glanced at one another, embarrassed and amused. So, their faces said, they got you too. Atwood moved serenely among them, shaking hands and making sharp remarks they all felt obliged to smile at.
‘It’s not fighting the Germans I object to. It’s going to war on behalf of these beastly Poles.’ He turned to a handsome, intense-looking young man with a broad, high forehead and thick hair. ‘And what’s your name?’
‘Pukowski,’ said the young man, in perfect English. ‘I’m a beastly Pole.’
Turing caught Jericho’s eye and winked.
In the afternoon the cryptanalysts were split into teams. Turing was assigned to work with Pukowski, redesigning the ‘bombe’, the giant decryptor which the great Marian Rejewski of the Polish Cipher Bureau had built in 1938 to attack Enigma. Jericho was sent to the stable block behind the mansion to analyse encrypted German radio traffic.
How odd they were, those first nine months of the war, how unreal, how – it seemed absurd to say it now – peaceful. They cycled in each day from their digs in various country pubs and guesthouses around the town. They lunched and dined together in the mansion. In the evenings they played chess and strolled through the grounds before cycling home to bed. There was even a Victorian maze of yew hedges to get lost in. Every ten days or so, someone new would join the party – a classicist, a mathematician, a museum curator, a dealer in rare books – each recruited because he was a friend of someone already resident in Bletchley.