The Professor, with his usual courtesy, expressed his pleasure at the meeting, though if the truth were told he had not expected to see a man of the little Doctor’s extreme ugliness. Then, when his visitor produced the precious copy of the dead man’s manuscript, the great scholar sat down and breathlessly read it through from end to end.

“This is exactly what I surmised from the burnt fragments,” he remarked, taking off his glasses as he turned to where the Doctor was sitting. “But the great and fascinating problem we have to solve is the whereabouts of the two keys to the cipher. One thing seems clear from the document, namely, that the dead man was Holmboe, the discoverer of the hidden secret.”

“Exactly. He knew the uncertainty of his life. Indeed he told me so when he had his first attack,” replied the little man, “the initials ‘P.H.’ were also upon his clothing.”

“He told you he was a Dane. But in all probability he was a Russian or a Finn,” remarked Griffin slowly turning over the leaves of a reference book before him. “Yes—here he is—Peter Holmboe, Professor of Hebrew at St. Petersburg, University, appointed four years ago. He apparently occupied a very high post for so young a man. He made the declaration in Hamburg, I see, therefore he had, no doubt, resigned his professorship in order to devote his time to finding capital to exploit the remarkable secret he had discovered.”

“Yes. But what’s the use of the secret without the key to the cipher?” queried the Doctor.

“None whatever. We must work to discover the key,” Griffin replied. “If I close study, discover the key myself.”

“Farquhar’s journey to Copenhagen was utterly fruitless. We were led there upon a wild goose chase,” the Doctor said. “The unfortunate fact is that others are also in search of the secret.”

“I am aware of that. But how did you discover it?”

“I was told by my friend—the man who secured for me this copy—an old friend named Mullet. He knows more than he will tell me!”

While the Doctor was speaking, Gwen had opened the door and entered the room.