Enigma (2 page)

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Jericho did not open his letters immediately. Instead he squared
his shoulders and tilted forwards into the wind. After a week in
his room, the richness of the oxygen pummelling his face made him
feel lightheaded. He turned right at the Junior Combination Room
and followed the flagstone path that led through the college and
over the little hump-back bridge to the water meadow beyond. To his
left was the college hall, to his right, across a great expanse of
lawn, the massive cliff-face of the chapel. A tiny column of
choirboys was bobbing through its grey lee, gowns flapping in the
gale.

He stopped, and a gust of wind rocked him on his heels, forcing
him half a step backwards. A stone passageway led off from one side
of the path, its arch grown over with untended ivy. He glanced, by
force of habit, at the set of windows on the second floor. They
were dark and shuttered. Here, too, the ivy had been allowed to
grow unchecked, so that several of the small, diamond-shaped panes
were lost behind thick foliage.

He hesitated, then stepped off the path, under the keystone,
into the shadows.

The staircase was just as he remembered it, except that now this
wing of the college was closed and the wind had blown dead leaves
into the well of the steps. An old newspaper curled itself around
his legs like a hungry cat. He tried the light switch. It clicked
uselessly. There was no bulb. But he could still make out the name,
one of three painted on a wooden board in elegant white capitals,
now cracked and faded.

TURING, A.M.

How nervously he had climbed these stairs for the first
time—when? in the summer of 1938? a world ago—to find a man barely
five years older than himself, as shy as a freshman, with a hank of
dark hair falling across his eyes: the great Alan Turing, the
author of On Computable Numbers, the progenitor of the Universal
Computing Machine…

Turing had asked him what he proposed to take as his subject for
his first year’s research.

“Riemann’s theory of prime numbers.”

“But I am researching Riemann myself.”

“I know,” Jericho had blurted out, “that’s why I chose it.”

And Turing had laughed at this outrageous display of hero
worship, and had agreed to supervise Jericho’s research, even
though he hated teaching.

Now Jericho stood on the landing and tried Turing’s door.
Locked, of course. The dust smeared his hand. He tried to remember
how the room had looked. Squalor had been the overwhelming
impression. Books, notes, letters, dirty clothes, empty bottles and
tins of food had been strewn across the floor. There had been a
teddy bear called Porgy on the mantelpiece above the gas fire, and
a battered violin leaning in the corner, which Turing had picked up
in a junk shop.

Turing had been too shy a man to get to know well. In any case,
from the Christmas of 1938 he was hardly ever to be seen. He would
cancel supervisions at the last minute saying he had to be in
London. Or Jericho would climb these stairs and knock and there
would be no reply, even though Jericho could sense he was behind
the door. When, at last, around Easter 1939, not long after the
Nazis had marched into Prague, the two men had finally met, Jericho
had nerved himself to say: “Look, sir, if you don’t want to
supervise me…”

“It’s not that.”

“Or if you’re making progress on the Riemann Hypothesis and you
don’t want to share it…”

Turing had smiled. “Tom, I can assure you I am making no
progress on Riemann whatsoever.”

“Then what…?”

“It’s not Riemann.” And then he had added, very quietly: “There
are other things now happening in the world, you know, apart from
mathematics…”

Two days later Jericho had found a note in his pigeonhole.

“Please join me for a glass of sherry in my rooms this evening.
F.J. Atwood.”

Jericho turned from Turing’s room. He felt faint. He gripped the
worn handrail, taking each step carefully, like an old man.

Atwood. Nobody refused an invitation from Atwood, professor of
ancient history, dean of the college before Jericho was even born,
a man with a spider’s web of connections in Whitehall. It was
tantamount to a summons from God.

“Speak any languages?” had been Atwood’s opening question as he
poured the drinks. He was in his fifties, a bachelor, married to
the college. His books were arranged prominently on the shelf
behind him. The Greek and Macedonian Art of War. Caesar as Man of
Letters. Thucydides and His History.

“Only German.” Jericho had learned it in adolescence to read the
great nineteenth-century mathematicians—Gauss, Kummer, Hilbert.

Atwood had nodded and handed over a tiny measure of very dry
sherry in a crystal glass. He followed Jericho’s gaze to the books.
“Do you know Herodotus, by any chance? Do you know the story of
Histiaeus?”

It was a rhetorical question; Atwood’s questions mostly
were.

“Histiaeus wished to send a message from the Persian court to
his son-in-law, the tyrant Aristagoras, at Miletus, urging him to
rise in revolt. However, he feared any such communication would he
intercepted. His solution was to shave the head of his most trusted
slave, tattoo the message onto his naked scalp, wait for his hair
to grow, then send him to Aristagoras with a request that he be
given a haircut. Unreliable but, in his case, effective. Your
health.”

Jericho learned later that Atwood told the same stories to all
his recruits. Histiaeus and his bald slave gave way to Polybius and
his cipher square, then came Caesar’s letter to Cicero using an
alphabet in which a was enciphered as d, b as e, c as f, and so
forth. Finally, still circling the subject, but closer now, had
come the lesson in etymology.

“The Latin crypta, from the Greek root kpvTTpt? meaning “hidden,
concealed”. Hence crypt, burial place of the dead, and crypto,
secret. Crypto-communist, crypto-fascist…By the way, you’re not
either, are you?”

“I’m not a burial place of the dead, no.”

“Cryptogram…” Atwood had raised his sherry to the light and
squinted at the pale liquid. “Cryptanalysis…Turing tells me he
thinks you might be rather good…”

♦

Jericho was running a fever by the time he reached his rooms. He
locked the door and flopped face down on his unmade bed, still
wearing his coat and scarf. Presently he heard footsteps and
someone knocked.

“Breakfast, sir.”

“Just leave it outside. Thank you.”

“Are you all right, sir?”

“I’m fine.”

He heard the clatter of the tray being set down, and steps
retreating. The room seemed to be lurching and swelling out of all
proportion, a corner of the ceiling was suddenly huge and close
enough to touch. He closed his eyes and the visions came up at him
through the darkness—

—Turing, smiling his shy half smile: “Tom, I can assure you, I
am making no progress on Riemann whatsoever…”

—Logie, pumping his hand in the Bombe Hut, shouting above the
noise of the machinery, “The Prime Minister has just been on the
telephone with his congratulations…”

—Claire, touching his cheek, whispering, “Poor you, I’ve really
got under your skin, haven’t I, poor you…”

—“Stand back”—a man’s voice, Logie’s voice—“Stand back, give him
air…”

And then there was nothing.

♦

When he woke, the first thing he did was look at his watch. He’d
been unconscious for about an hour. He sat up and patted his
overcoat pockets. Somewhere he had a notebook in which he recorded
the duration of each attack, and the symptoms. It was a
distressingly long list. He found instead the three envelopes.

He laid them out on the bed and considered them for a while.
Then he opened two of them. One was a card from his mother, the
other from his aunt, both wishing a happy birthday. Neither woman
had any idea what he was doing and both, he knew, were guiltily
disappointed he wasn’t in uniform and being shot at, like the sons
of most of their friends.

“But what do I tell people?” his mother had asked him in despair
during one of his brief visits home, after he had refused yet again
to tell her what he did.

“Tell them I’m in government communications,” he had replied,
using the formula they had been instructed to deploy in the face of
persistent enquiries.

“But perhaps they’d like to know a little more than that.”

“Then they’re acting suspiciously and you should call the
police.”

His mother had contemplated the social catastrophe of her bridge
four being interviewed by the local inspector, and had fallen
silent.

And the third letter? Like Kite before him, he turned it over
and sniffed it. Was it his imagination or was there a trace of
scent? Ashes of Roses by Bourjois, a minuscule bottle of which had
practically bankrupted him just a month earlier. He used his slide
rule as a paperknife and slit the envelope open. Inside was a cheap
card, carelessly chosen—it showed a bowl of fruit, of all
things—and a standard message for the circumstances, or so he
guessed, never having been in this situation before. “Dearest
T…always see you as a friend…perhaps in the future…sorry to hear
about…in haste…much love…” He closed his eyes.

♦

Later, after he had filled in the crossword, after Mrs Sax had
finished the cleaning, after Bickerdyke had deposited another tray
of food and taken it away again untouched, Jericho got down on his
hands and knees and tugged a suitcase from beneath his bed and
unlocked it. Folded into the middle of his 1930 Doubleday first
edition of The Complete Sherlock Holmes were six sheets of foolscap
covered in his tiny writing. He took them over to the rickety desk
beside the window and smoothed them out.

“The cipher machine converts the input(plain language, P) into
the cipher (Z) by means of a function f. Thus Z=f(P,K) where K
denotes the key…”

He sharpened his pencil, blew away the shavings and bent over
the sheets.

“Suppose K has N possible values. For each of the N assumptions
we must see if f(Z,K) produces plain language, where f’1 is the
deciphering function which produces P if K is correct.”

The wind ruffled the surface of the Cam. A flotilla of ducks
rode the waves, without moving, like ships at anchor. He put down
his pencil and read her card again, trying to measure the emotion,
the meaning behind the flat phrases. Could one, he wondered,
construct a similar formula for letters—for love letters or for
letters signalling the end of love?

♦

“The input (sentiment, S) is converted into a message (M) by the
woman, by means of the Junction w. Thus M=w(S,V) where V denotes
the vocabulary. Suppose V has N possible values…”

The mathematical symbols blurred before his eyes. He took the
card into the bedroom, to the grate, knelt and struck a match. The
paper flared briefly and twisted in his hand, then swiftly turned
to ash.

♦

Gradually his days acquired a shape.

He would rise early and work for two or three hours. Not at
cryptanalysis—he burned all that on the day he burned her card—but
at pure mathematics. Then he would take a nap. He would fill in The
Times crossword before lunch, timing himself on his father’s old
pocket watch—it never took him more than five minutes to complete
it, and once he finished it in three minutes forty. He managed to
solve a series of complex chess problems—“the hymn tunes of
mathematics”, as G.H. Hardy called them—without using pieces or a
board. All this reassured him his brain had not been permanently
impaired.

After the crossword and the chess he would skim through the war
news while trying to eat something at his desk. He tried to avoid
the Battle of the Atlantic (
DEAD MEN AT THE OARS: U-BOAT
VICTIMS FROZEN IN LIFEBOATS
) and concentrated instead on
the Russian Front: Pavlograd, Demiansk, Rzhev…the Soviets seemed to
recapture a new town every few hours and he was amused to find The
Times reporting Red Army Day as respectfully as if it were the
King’s Birthday.

In the afternoon he would walk, a little further on each
occasion—at first confining himself to the college grounds, then
strolling through the empty town, and finally venturing into the
frozen countryside—before returning as the light faded to sit by
the gas fire and read his Sherlock Holmes. He began to go into Hall
for dinner, although he declined politely the Provost’s offer of a
place at High Table. The food was as bad as at Bletchley, but the
surroundings were better, the candlelight flickering on the
heavy-framed portraits and gleaming on the long tables of polished
oak. He learned to ignore the frankly curious stares of the college
staff. Attempts at conversation he cut off with a nod. He didn’t
mind being solitary. Solitude had been his life. An only child, a
stepchild, a “gifted” child—always there had been something to set
him apart. At one time he couldn’t speak about his work because
hardly anyone would understand him. Now he couldn’t speak of it
because it was classified. It was all the same.

By the end of his second week he had actually started to sleep
through the night, a feat he hadn’t managed for more than two
years.

Shark, Enigma, kiss, bombe, break, pinch, drop, crib—all the
weird vocabulary of his secret life he slowly succeeded in erasing
from his conscious mind. To his astonishment, even Claire’s image
became diffuse. There were still vivid flashes of memory,
especially at night—the lemony smell of newly washed hair, the wide
grey eyes as pale as water, the soft voice half amused, half
bored—but increasingly the parts failed to cohere. The whole was
vanishing.

He wrote to his mother and persuaded her not to visit him.

“Nurse Time,” the doctor had said, snapping shut his bag of
tricks, “that’s who’ll cure you. Mr Jericho. Nurse Time.”

Rather to Jericho’s surprise it seemed that the old boy was
right. He was going to be well again. “Nervous exhaustion” or
whatever they called it was not the same as madness after all.