Enigma Read Online Free PDF Page B

a fact that that was the case—how the hell were the coastal weather stations deciphering the U-boat's transmissions?
    It was a question no one had bothered to stop and ask, yet it was fundamental.
    To read a message enciphered on a four-rotor machine you had to have a four-rotor machine.
    Or did you?
    If it is true, as someone once said, that genius is 'a zigzag of lightning across the brain', then, in that instant, Jericho knew what genius was. He saw the solution lit up like a landscape before him.
    He seized his dressing gown and pulled it over his pyjamas. He grabbed his overcoat, his scarf, his socks and his boots and in less than a minute he was on his bike, wobbling down the moonlit country lane towards the Park. The stars were bright, the ground was iron-hard with frost. He felt absurdly euphoric, laughing like a madman, steering directly into the frozen puddles along the edge of the road, the ice crusts rupturing under his tyres like drum skins. Down the hill he freewheeled into Bletchley. The countryside fell away and the town spread out beneath him in the moonlight, familiarly drab and ugly but on this night beautiful, as beautiful as Prague or Paris, perched on either bank of a gleaming river of railway tracks. In the still air he could hear a train half a mile away being shunted in the sidings—the sudden, frantic chugging of a locomotive followed by a series of clanks, then a long exhalation of steam. A dog barked and set off another. He passed the church and the war memorial, braked to avoid skidding on the ice, and turned left into Wilton Avenue.
    He was panting with exertion by the time he reached the Hut, fifteen minutes later, so much so he could barely blurt out his discovery and catch his breath and stop himself from laughing at the same time:'—They're—using—it—as—a—three-rotor—machine—they're—leaving—the—fourth—rotor—in—neutral—when—they—do—the—weather—stuff—the—silly—bloody—buggers -'
    His arrival caused a commotion. The night shift all stopped working and gathered in a concerned half-circle round him—he remembered Logie, Kingcome, Puck and Proudfoot—and it was clear from their expressions they thought he really had gone mad. They sat him down and gave him a mug of tea and told him to take it again, slowly, from the beginning.
    He went through it once more, step by step, suddenly anxious there might be a flaw in his logic. Four-rotor Enigmas were restricted to U-boats and Sainte-Assise: correct? Correct. Therefore, coastal stations could only decipher three-rotor Enigma messages: correct? Pause. Correct. Therefore, when the U-boats sent their weather reports, the wireless operators must logically disengage the fourth rotor, probably by setting it at zero.
    After that, everything happened quickly. Puck ran along the corridor to the Big Room and laid out the best of the weather cribs on one of the trestle tables. By 4 A.M. they had a menu for the bombes. By breakfast one of the bombe bays was reporting a drop and Puck ran through the canteen like a schoolboy shouting: 'It's out! It's out!'
    It was the stuff of legend.
    At midday Logie telephoned the Admiralty and told the Submarine Tracking Room to stand by. Two hours later, they broke the Shark traffic for the previous Monday and the Teleprincesses, the gorgeous girls in the Teleprinter Room, began sending the translated decrypts down the line to London. They were indeed the crown jewels. Messages to raise the hairs on the back of your neck.

    FROM: U-BOAT TO CAPTAIN SCHRODER

    FORCED TO SUBMERGE BY DESTROYERS. NO CONTACT. LAST POSITION OF ENEMY AT 0815 NAVAL GRID SQUARE 1849.
    COURSE 45 DEGREES, SPEED 9 KNOTS.

    FROM: GILADORNE

    HAVE ATTACKED. CORRECT POSITION OF CONVOY IS AK1984. 050 DEGREES. AM RELOADING AND KEEPING CONTACT.

    FROM: HAUSE

    AT 0115 IN SQUARE 3969 ATTACKED, FLARES AND GUNFIRE, DIVED, DEPTH CHARGES. NO DAMAGE. AM IN NAVAL GRID SQUARE AJ3996. ALL TIN FISH, 70 CBM.

    FROM: FLAG