“You know how very slight our clues have been up to the present?” he said after a pause. “Your brother was murdered in a café in Paris; murderer unknown; motive of the crime unknown. A man who is now in his grave appeared on the scene half-an-hour after the murder was committed. He found close to the body of the murdered man half a sheet of paper on which something in cipher was written, and at the foot of the cipher in place of signature were some very peculiar hieroglyphics. That piece of paper has lain in my possession for years. I have studied the cipher and the hieroglyphics which stood in place of a signature with the utmost care. I have transposed the alphabet in all manner of ways, not only at my office when I had a moment to spare, but over my evening pipe at home. With infinite trouble I have made out a few words, but nothing to give me any clue to the identity of the man to whom the paper belonged. “The gentleman who is now dead and who appeared on the scene of the murder half an-hour after it was committed, says he saw a man leaving the café who looked much excited—was dark, and of unusual height and breadth. His attention was attracted to this man because he wore no hat, and he had also a peculiar mark above his upper lip. He described the mark as something in the shape of a death’s head and cross-bones, but could not positively be sure on that point. By evidence taken at the time it was made abundantly plain that this man must have been the murderer. He has never been captured, and our only chance of finding him consists in following up the clue which the mysterious paper in my possession can give us. “There is little or no doubt either that the murder was premeditated, as the writing was an appointment, bringing the murdered man to the spot. My business, therefore, Mrs. Rowton, is to find the man who wrote the letter, and who has that peculiar mark on his face.” “Yes,” said Nance, with some impatience. “Remember,” she added, “that I have heard all this discussed many, many times.” “Yes, madam.” “And have you nothing further to say?” “A little more. Have you any objection to my locking the door?” “Certainly not. But is it necessary? No one will disturb us during our interview.” “I am none so sure of that,” replied the detective. “There is a young woman in this house who would think very little of eavesdropping.” “Whom do you mean?” asked Nance with a start. “A dark-eyed slip of a girl, madam—she came into this room a few minutes ago to fetch a book. I looked at her and she looked at me. If ever a face had cunning in it, hers is the one.” “My maid, Hester Winsome,” thought Nance to herself. Aloud she said: “Well, lock the door, and we shall be safe.” Crossley did so. As he resumed his seat, he said: