"Is it something in connection with that forged letter to Mallowe?" asked Ramon quickly. "Perhaps," the detective admitted. He shrugged, then added leniently, "I think, before proceeding any further with that branch of the investigation, it would be well to know who obtained the notepaper with the hotel letterhead, and if the paper itself was genuine. Bring me back some of the hotel stationery, also, that I may compare it with that used for the letter." A discreet knock upon the door heralded the coming of an operative, in response to Blaine's touch upon the bell. "There has been a slight disturbance in the outer office, sir," he announced. "A man, who appears to be demented, insists upon seeing you. He isn't one of the ordinary cranks, or we would have dealt with him ourselves. He says that if you will read this, you will be glad to assent to an interview with him." He presented a card, which Blaine read with every manifestation of surprised interest. "Tell him I will see him in five minutes," he said. When the operative had withdrawn, the detective turned to Ramon. "Who do you think is waiting outside? The man who threatened Pennington Lawton's life ten years ago, the man whose name was mentioned by the unknown visitor to the library on the night Lawton met his death: Herbert Armstrong!" "Good heavens!" Ramon exclaimed. "What brings him here now? I thought he had disappeared utterly. Do you think it could have been he in the library that night, come to take revenge for that fancied wrong, at last?" "That is what I'm going to find out," the detective responded, with a touch of grimness in his tones. "But you don't mean--it isn't possible that Mr. Lawton was murdered! That he didn't die of heart-disease, after all!" "I traced Armstrong to the town where he was living in obscurity, and followed his movements." Blaine's reply seemed to be purposely irrelevant. "I could not, however, find where he had been on the night of Mr. Lawton's death. Now that he has come to me voluntarily, we shall discover if the voice Miss Lawton overheard in that moment when she listened on the stairs, was his or not.... Come back this afternoon, Mr. Hamilton, and I will give you full information and instructions about that Long Bay errand. In the meantime, guard yourself well from a possible attack, although I do not think another attempt upon your life will be made so soon. Take this, and if you have need of it, do not hesitate to use it. We can afford no half-measures now. Shoot, and shoot to kill!" He opened a lower drawer in his massive desk and, drawing from it a business-like looking revolver of large caliber, presented it to the lawyer. With a warm hand-clasp he dismissed him, and, going to the telephone, called up Anita Lawton's home.