“But what are they?” asked Bethany.
“You solved that problem,” said Arthur, winking at her, “when you found that sixteenth-century inventory of the manuscripts. A key word is usually taken from another document. The combinations of numbers probably indicate a location in another manuscript—it could be a page number and line number; or a line number and word number . . .”
“Or a manuscript number and leaf number,” said Bethany. “We know from the right-hand set of numbers on the inventory that whoever prepared it liked to use leaf numbers instead of page numbers.”
“You’ve figured it out, haven’t you?” said Arthur.
“I don’t get it,” said David. “What am I missing?”
“This manuscript was almost certainly made at the time of the Reformation, to protect whatever secrets are encoded here from the king’s commissioners. A couple of weeks ago, Bethany found another document that was made at the same time.”
“An inventory of all the manuscripts in St. Ewolda’s library,” said Bethany. “It’s dated October 28, 1539.”
“Tell them the best part,” said Arthur.
“Each item is numbered with Roman numerals,” said Bethany.
“The numbers are out of sequence,” said Arthur, picturing the left-hand column of numbers on the inventory that Bethany had not understood. “And written in a different hand than the inventory. I think one person prepared the list and then whoever encrypted the manuscript added the numbers.”
“Of course,” said Bethany excitedly. “The inventory is the key to the code. It’s perfect—there are thirty-five manuscripts and for Roman numerals written in five digits or fewer and not including L, there are thirty-five possible numbers.”
“So you think the number pairs in the cipher text refer to the manuscripts?” said David.
“Exactly,” said Arthur. “Probably the first number is the manuscript number and the second is the leaf number, with the key word being the first word at the beginning of the leaf. Or it could be the last word. I haven’t actually tried it yet, but it all makes sense and it explains all those pesky combinations of U, Q, and D.”
“Do we still have all the manuscripts from this 1539 inventory?” said Oscar.
“Aye, there’s the rub,” said Arthur. “Bethany checked it against the library and we’re missing sixteen of the thirty-five titles—they were probably stolen by the king’s commissioners during the Reformation.”
“Still,” said Oscar, “if you could decipher over half the text, that would be better than nothing.”
“So let’s get to it,” said David.
—
For the first hour or so they worked as a team. David and Bethany looked up possible key words in the relevant manuscripts—copying out the first and last words on every leaf up to thirty-nine. Arthur and Oscar worked on decoding the Roman numerals. Over each string of letters that contained combinations of U, Q, and D, they wrote the corresponding number pair. Within an hour they had amassed enough key words and extracted enough number pairs to start to work. While Bethany and David continued to record key words, Oscar and Arthur began to apply the rules of a simple substitution alphabet cipher to the word strings for which they had corresponding key words. Arthur had been sure his idea had been right. It made such perfect sense, but as he and Oscar worked their way through key word after key word, they still came up with nothing but gibberish. Occasionally a word or two would leap out at them, but that might have been simple statistics—a monkeys-typing-Hamlet sort of thing. Bethany and David eventually exhausted the manuscripts in the library that corresponded with the ones on the inventory. Bethany, paranoid about working on her own computer because she feared Jesse Johnson was watching every keystroke, borrowed David’s laptop and delved into some sort of research. At seven, David went off to a dinner date.
“It’s not working,” said Oscar after David had left. “We’ve tried almost fifty key words. There must be some other trick to it.”
“The chapter has to decide whether to accept Jesse Johnson’s offer in less than”—Arthur looked at his watch—“seventy-two hours. I think there is something in here that will make that offer superfluous, and I’m not giving up until I find it.”
“You know, Arthur,” said Bethany, closing the laptop and looking across at the two men, “Einstein said insanity is doing the same thing over and over and expecting different results.”
“Einstein never said that,” said Arthur.
“Well, I just did,” she said. “Oscar, would you like to go get some dinner?”
“You’re just going to give up?” said Arthur.
“No,” said Oscar. “We’re going to eat food. And if either one of us thinks of a new approach, we’ll be back to try it.”
“I can’t eat,” said Arthur, staring at the meaningless letters swimming on the page in front of him.
“You can,” said Bethany. “You choose not to.”
“You go on,” said Arthur. “I just . . . I have to keep trying.”
“Don’t drive yourself crazy, old man,” said Bethany, and she gave him a quick peck on the cheek. Arthur felt a surge of excitement as her lips brushed his skin, but he immediately suppressed it. This is no time for love, he thought—especially hopeless love. If he was going to engage in something hopeless, it was going to be code breaking. He deciphered the next Roman numeral, found the corresponding key word, and set to work turning one group of meaningless letters into another.
—
Wednesday had been a lost day of deciphering, since Arthur, Oscar, David, and Bethany had all had a full day of work. Arthur had returned to the library after the special Evensong for the feast of the Venerable Bede and spent a few frustrating hours attacking the coded manuscript. Now he stood in the early morning light listening to approaching footsteps on the stairs.
“Did you stay up all night again?” said Bethany, stepping into the library.
“Actually, I fell asleep on the sofa in the anteroom. It just seems like I’m . . . I mean, we’re so close. I keep getting words here and there, but never enough to string together a sentence.”
“You need to get out of here for a little while,” said Bethany.
“Did I miss Morning Prayer?”
“It’s five a.m.”
“Good Lord, I had no idea it was so early. What are you doing here?”
“I couldn’t sleep, so I thought I’d take a walk. Come with me. Show me where this whole thing started.”
“It all started right here,” said Arthur. “The cathedral is built on the site of the original monastery, you know that.”
“Yes, but we think the manuscript was written at St. Ewolda’s Priory. You said you would show me the ruins.”
“A walk by the river at five in the morning?”