“Well, you can find out whether they’re dead, anyhow.”
“And if they’re still alive?”
“Well, scout around somehow. Do anything that occurs to you. This business ought to be rather fun, if we exercise a little ingenuity.”
“Meanwhile, let’s have another look at those documents. We don’t seem to have made much out of them, and that’s a fact.”
They sat for several minutes in silence, re-reading the copy Reeves had made of the anonymous letter. It was undated; the address was in printed capitals; it had been post-marked in London at starting, and at Paston Whitchurch on arrival. The content of the message was a mere series of numbers, as follows:
| 8 | 7 | 5 |
| 18 | 4 | 7 |
| 21 | 2 | 3 |
| 25 | 6 | 4 |
| 31 | 4 | 8 |
| 74 | 13 | 9 |
| 92 | 29 | 7 |
| 97 | 5 | 3 |
| 113 | 17 | 13 |
| 10 | 12 | 13 |
“Unless they’re sums of money,” said Gordon, “I can’t make head or tail of it all. And if they were sums of money, it would be a queer way to arrange the spacing.”
“Wait one moment,” said Reeves, “I believe I’ve got the idea of it.” He put his hand to his forehead. “Yes, that does it. It’s a cipher, of course, otherwise there’d be something to explain what it’s all about. It will be a book cipher; the first figure gives you the page, the second the line, and the third the word in the line. How’s that?”
“That’s devilish ingenious,” admitted Gordon, “but you can hardly prove it.”
“I can practically prove it,” said Reeves. “Look here, the man wanted to spell out a message in ten words. There was a book, arranged upon somehow beforehand. The first few words were ordinary words, that you could find anywhere on any page: and naturally, to save himself and the other man trouble in counting, he took them from the top of the page, so you get lines 7, 4, 2, 6, and 4 of pages 8, 18, 21, 25 and 31. The sixth word he wanted was an obscure sort of word, perhaps even a proper name. He had to go right on to page 74, and even then he could only find his word on the 13th line of it. Then the next two words came easy, comparatively, but the ninth word was a brute, he couldn’t find it till page 113, and on the 17th line at that. And by that time he’d got nearly to the end of the book—a book, then, of only 120 pages or so probably; a paper edition, I suspect—so he had to go back to the beginning again, which he hadn’t meant to do.”