In the afternoon, Professor Dusenberry, dressed in a frock coat and top hat, although he was at sea and the weather was warm, came into the wireless room. He wanted to send a message, he said, a wireless to London. He was very cautious about inquiring the price and all the details before he sat down to write out his dispatch. When it was completed he handed it to Jack with his thin fingers, and asked that it be dispatched at once. Then he retreated, or rather faded, from the wireless room. Jack scanned the message with thoughtful eyes. It seemed an odd radiogram for a college professor, such as he had heard Prof. Dusenberry was, to be sending. It read as follows:
"Meet me at three on the granite paving-stones. The weather is fine, but got no specimens. There is no suspicion as you have directed, but I'm afraid wrong."
F.
"Well, that's a fine muddle for somebody to make out when they get it," mused Jack, as he sent out a call for the Fowey Station.
"Must be some sort of a cipher the old fellow is using. He's a dry sort of old stick. Goodness! How scared he was when he saw that man lying outside his door. I thought he was going to faint or something."
"Wonder what sort of a cipher that is," mused Jack, as he waited for an answer to his call. "Looks to me as if it's one of those numerical ciphers where every second or third or fourth or fifth word is taken from the context and composes a message. Guess I'll try and work it out some time. It'll be something to do. And, hullo, he signs himself 'F'."
Jack looked up at the printed passenger-list that hung before him. "Professor F. Dusenberry" was the last of the "D's"
"His initial," thought Jack, "but it's a funny coincidence that it should be the same as that of the man the diamond merchant was warned to watch out for, and that it should have been the professor's door outside of which he was struck down."