Carmichael, who met them at the door of the club, was more sympathetic. In his view, Miss Rendall-Smith had given the photograph to Davenant, not realizing his identity with Brotherhood, and had thought it impossible that Davenant should have allowed so precious a document to pass out of his possession. But he was in high spirits, having made, he said, a little discovery of his own.
“You know you told me about your efforts to identify the book from which the cipher was taken—the cipher on the postcard? Well, you went the right way to work, but not, if you will excuse my saying so, taking all the possibilities into account. Supposing that Brotherhood had the actual book with him in the carriage when he left London, you have to remember that he changed at Paston Oatvile. Now, I asked myself, what if, from some carelessness or want of interest, he should have left the book in that first-class railway carriage? That train, you see, stops for good at Paston Oatvile, and is cleaned out there the same night.”
“Of course. I was a fool not to think of that.”
“Well, I went off to the station while you were away, and repeated your own trick.”
“Selecting an imaginary book of your own, I suppose?”
“No; it is always better to put one story about the country-side rather than two. I said that a friend of mine had lost a copy of The Sorrows of Satan, and was anxious to recover it. The porter referred me to another porter, the other porter, to be accurate, and he informed me that he had found, in that train, a copy of a book called Immorality.”
“But there isn’t a book called that.”
“I know. Many might be, but none are. However, I saw what was up. The porter, by a train of thought which I find myself unable to follow, had taken the book home to his wife: and it was no surprise to me when she produced a copy of Momerie’s Immortality. It had been a disappointment to her, it seemed, and she made no difficulty about parting with it.”
“But have you any reason for thinking it’s the book we’re looking for?”
“Yes. There are a lot of lines down the side, queries and shriek-marks occasionally, which convince me that the thing was in Brotherhood’s hands. Only, of course, we want your copy of the cipher to read it from.”