Notes from the Grey Tower

During that period of time, I often reminisced about my mother. When I looked through her notes, my father’s comments were often written beside her tidy handwriting. In my memory, my mother was always reading on the sofa, and when I trundled up to her, she would put her book down to sit me on her knee, humming softly. 

Edgar was right. If I couldn’t even trust my own father and mother, who else could I trust?

My mother’s blue-grey eyes were beautiful, and fell upon everyone who had spoken to her gently. Her gentle gaze had once fallen upon me, upon my father, and upon Andemund, too.

Andemund had told me that my mother’s ideas were unique when it came to cryptology. As the days passed by while I read her notes, I realized that her true talents had laid in mathematics, though she had sacrificed most of her life on decrypting codes for her home country. Even after her retirement, in her last notebook, she was still trying to transcribe cryptanalytic methods into mathematical formulae. These formulae were used in encrypting messages before the Enigma was born— they were the early encrypting machines. 

I thought it was her love for England that had allowed her to come this far.

What little of her short life was now preserved in the photograph, and she would forever be the gentle woman whom I knew so well in my memory. 

I began combing through the formulae that she had left behind in my free time. During that period, I met Andemund again, once. 

Our meeting was pure coincidence. My interests had returned to mathematics once again. Cambridge was where mathematical geniuses gathered, and there was never a lack of people to socialize with if you were willing to look for them. I entered a mathematics society and befriended many people there. One of them was Emily Rotter, who published a paper on abstract algebra in an academic newsletter when she was in her second year of college. And Adam Mensa, a twenty-six year old American visiting professor at Cambridge. On the weekends Lindon would occasionally join us, and when asked about his job, he would always say he worked at the Golf, Cheese and Chess Society. Under my friends’ encouragement, I wrote up a paper on group theory, and through Emily contacted a professor who lived in urban London for consultation— a big shot in the mathematic world at the time, Professor Harling Watt. 

It had just stopped snowing in the midst of winter. I was made to wait outside the study by the butler. A while later, when the door opened, Professor Watt and Andemund walked out. Behind them was a man with rimmed glasses in military uniform. Andemund paused in surprise when he saw me, and Professor Watt explained while smiling. “This is Alan Caster, a third-year from Cambridge University who is quite talented at mathematics. He recently authored a rather interesting thesis on group theory. Andemund, perhaps you would be interested— Oh, do you know each other already?”

Andemund brushed past me. “Alan used to be my student— Professor Watt, if you are interested in the work we do at Bletchley Park, please contact me anytime.”

I chased him outside. Andemund walked quickly, and had no notion of waiting for me at all. 

The man with rimmed glasses in military uniform reminded him. “The student’s chasing after you.”

“I heard from Edgar that you came to find me?” I yelled. 

He turned to look at me. His green eyes slimmed into slits. 

“I did not. Your friend mistook another person for me.”

The words tumbled clumsily from my lips. “I know you’re suspicious of me. I only want to tell you, my parents— they’re innocent.”

Andemund’s black sedan was parked at the empty road next to the professor’s backyard. A thin layer of snow had collected on its roof. He wore a heavy black winter overcoat. Peter stood stiffly by the car door, waiting for him. 

Half a year had passed since I’d last seen him, but Andemund showed little change, perhaps only a little more tiredness in his expression. In the heat of the moment, I called out to him. “You’re still in need of people— you invited Professor Watt to join. If you’re willing to trust me, I can help you. You know I like you.”

Peter opened the door to the car, though Andemund didn’t get in and instead turned to face me. Suddenly, he closed the distance between us. I was too stunned to react. Our faces were in such close proximity that I could feel his breath on my cheek. 

“Leave the ‘mathematics society’ you joined,” he said. “Stop presenting your theses to the academic world.”

I didn’t know what made Andemund suddenly lose it. “You have no right to restrict my freedom!”

“And, stop frequenting bars and making ‘friends’ there.”

I was incredulous. “You’ve been spying on me?!”

After parting with Andemund, I had a period in which I indulged freely in bars at night, though was later punched out of my reverie by Edgar. I wasn’t the only gay man in Cambridge. I had made several ‘friends’ there, but didn’t go any further than that. I thought I had been careful enough, and I’d even managed to keep Edgar in the dark about it. 

But Andemund knew.

“Of course you would be investigated. You know about the secret of Bletchley Park.” He paused, his tone of voice suddenly softening. “Don’t worry. It’ll only be for a short time. It won’t affect your daily life.”

“You still don’t trust me.”

Andemund nodded. 

“So, we broke up with each other.”

He blinked, as if trying to make sense of the causal relationship between my words, and nodded again.

“Therefore, you have no right to interfere with my personal life. What I do with my friends, has nothing to do with you.”

Andemund went quiet for a brief second. “As you wish,” he told me, and returned to his sedan. Peter pulled the door open for him. Rimmed glasses followed behind, and gave me a curious look before he got in the car. 

To Andemund, his attempt at romance was only something he did to pass the time, and I had foolishly thought that all of it had been real. I liked Andemund. I thought, if he couldn’t trust me, and if we couldn’t be together, then we would each return to our own lives. I swore I would never beg to stay by his side again. 

Edgar congratulated me on my revelation. “Why don’t you try going out with another person— for example, let’s say, me?”

I kicked him. “I thought your lover was the one-armed Venus— the one in the arts building.”

I tried returning to life before I met Andemund, but instead I spent the month that followed wallowing in increasing despair. I had rented a car for a drive with a friend I’d made from a bar, but the car broke down in the middle of the trip; I became acquainted with a rather attractive man, saved up money for dinner at a high-end restaurant, but the restaurant bookings turned out to be full; I was unable to even buy tickets to an art gallery that I went to with Edgar. The staff at the ticket booth waved the stack of unsold tickets at us, and told us with a grin, “We’re sold out.”

While Edgar argued with the staff, I inwardly cursed Andemund ten thousand times over.

Deprived of all other options, I could only pass my time on the third floor of the library every day at the mathematics society. Other members often came here for a cup of coffee and a chat after dinner, and I was the only one who stayed in the activity room doing nothing all day. Aside from me though, Lindon was the next person who spent the most time here. He would only come during the weekends, appearance disheveled and stubble unshaven, and stay late into the night without returning home. While discussions went on among the society members with fervor, he would sullenly sit in a corner and listen without comment.

One day, he called for me. “Alan, would you sit down and have a drink with me?”

Lindon drank until midnight once he got going. The students had mostly left by then, and he circled around topics of no particular importance as he talked. I asked him. “Are you really this averse to going back to Bletchley Park?”

He pulled at his hair. “Is it that obvious?”

Under the dim illuminance of the gas lamps, he asked me. “Alan, did you really crack Code S?”

I shrugged and said nothing. 

“I heard the adjutant that drives for Garcia, Peter, talk about you. He asked Mr. Garcia, why weren’t you accepted into Bletchley park despite having cracked Code S? I was just passing by then…”

“I can’t join.” I answered succinctly.

I couldn’t see Lindon’s face clearly in the darkness, and only heard him speak. “Everyone that works there is a genius. Endless meetings and discussions every day, my work completely unfinished— it’s a living hell, working there.”

The cryptanalysis done in Bletchley Park could be split into two types, one being immediate decryption, and the other done by a group of ten to twenty people who would spend weeks decrypting a long piece of writing. The ciphertexts that could be immediately deciphered were often comparatively easy, and their contents were often not of much importance. As a newcomer, it wasn’t strange that he would be assigned to the group that did immediate decrypting. 

But his results there were unsatisfactory.

Lindon had been treated as a mathematical genius since he was young. Even at Cambridge, his talents were still appreciated by many. But things were different at Bletchley Park. Being a ‘genius’ was only a basic requirement for working there, and everyone there had their own unique talents in their own field. Andemund didn’t only recruit mathematical geniuses, but also the champions of international chess competitions and experts at languages. It was apparent that Lindon didn’t stand out much there. 

We weren’t too much on liking each other. But he made a decision to go against the rules of Bletchley Park. He went to me for help. 

He had snuck out an encrypted message from Bletchley Park. 

“Help me, Alan. I have no one else I can beg for help now.” he told me. 

The first step to decrypting a message was to try and guess the method the encryptor had used to encrypt the message. You had to deduce the method in which your opponent used to encrypt the letters in order to reverse it and decrypt the code. In the last world war, the substitution cipher was widely used: for example you would replace ‘a’ with ‘r’, ‘p’ with ‘o’, ‘l’ with ‘f’ and ‘e’ with ‘w’. The word, ‘apple’, would thus be encrypted into the word ‘roofw’.  Ciphers like these were extremely easy to solve, since the probability of appearance of each letter in the alphabet was basically unchanged for every text— for example, in English, the probability of appearance of ‘e’ was the highest, while that for ‘z’ was the lowest. The probability of appearance of the letter combination ‘eh’ was much lower than that of ‘he’. Since the emergence of letter frequency analysis, ciphers like these had all become practically useless. 

And the cipher Lindon had given me, was only an improved version of the substitution cipher. 

The encryptor had cleverly created a letter substitution table in order to subvert decryption via letter frequency analysis. While encrypting the plaintext, when a letter appeared for the first time, it would be encrypted with the first row of the table, and when the same letter appeared for the second time, it would be encrypted with the second row of the table, and so on. 

“So that’s how it managed to subvert decryption by simple letter frequency analysis.” I explained to Lindon. “This isn’t difficult at all.”

We sped through our calculations in the feeble lighting of the activity room, and at four in the morning, I handed him a piece of paper with the decrypted text.

“No matter how the substitution table changes, when the letter substitution table finally runs out of rows, the process will have to repeat and the letters will be encrypted with the first row of the table again. As long as the ciphertext is long enough, decryption will always be possible.”

This was where my assisting of Lindon’s cryptanalysis work started. I knew what I did went against the rules Andemund had laid down for Bletchley Park, but I was only here to prove my loyalty towards England, and my ability to enter Bletchley Park and work for the country. I had excessively trusted in myself, and completely trusted in Lindon as well. 

[8/2/2021] Translator’s notes: Took some liberties with character names and didn’t bother to find real world equivalents. Also took a bit of liberties with the explanation of what a substitution cipher is since I didn’t want to find the professional term for what I literally translated as ‘letter substitution table’. Hopefully it’s still understandable because I sure have no idea what I wrote until I read the original paragraph five times and retranslated the English twice. (lord save my reading comprehension skills)

Translated today’s chapter instead of studying. My god I can already feel how screwed I am for my finals. But my love for Andemund prevailed and I am one chapter closer to the part where the romance goes from sweet slow(quick??) burn pining to rollercoaster ride of heart attacks. Hope that’s not too much of a spoiler(????) Did a quick proofreading check but too tired to make big edits. Will edit tomorrow hopefully. (le sigh at my finals…)

The next update, by the way, will probably come during Chinese New Year– or somewhere near it, I can’t be bothered to look up the lunar calendar. Happy early new year to the select few who’s been reading this translation as it updates!^^

[10/2/2021] Translator’s notes: Made some minor grammatical edits.