"You will, of course, perceive, Miss Patterson, that the probabilities are that this letter is a hoax; the signature, Philip Walter Augustus Parker, in itself suggests a hoax. Then there is the absence of an address. And, of course, we have the verdict of the coroner's jury, and the evidence on which it was found. I am quite prepared to learn that I have come to Russell Square, and troubled you with my presence, for nothing. But at the same time, in my position, I did not feel justified in not coming, on the very off-chance of making the acquaintance of Philip Walter Augustus Parker. It is now on the stroke of half-past three; we will give him a few minutes' grace, after which--if, as I expect will be the case, there are still no signs of him--I'll take myself off, with apologies, Miss Patterson. But should he by any strange chance put in an appearance, I would ask you to have him at once shown in here." Hardly had the inspector done speaking than there was the sound of an electric bell and a rat-tat-tat at the front door. The trio in the dining-room could scarcely have seemed more startled had they been suddenly confronted by a ghost. The inspector's voice sank to a whisper. "If the name's Parker, would you mind asking the servant--in here?" A gesture supplied the words he had omitted in his sentence. He held the door open so that Gladys could speak to the maid who was coming along the hall. She did so, also in lowered tones. "If that's a person of the name of Parker show him at once in here." She withdrew; the inspector shut the door; there was a pause; no one spoke; each of the three stood and listened. They could hear the front door opened and steps coming along the hall. Then the dining-room door was opened by a maid, who announced: "Mr. Parker." There entered the little man who had followed the example set by Rodney of getting out of the train in Redhill Tunnel. CHAPTER XXIII NECESSARY CREDENTIALS The moment he appeared Rodney knew that he had been expecting him; that somewhere at the back of his mind there had been a feeling that it was he who was coming. His impulse was to take him by the throat and crush the life out of him before he had a chance of saying a word; which was the impulse of a badly frightened man. But he seldom lost his presence of mind for long; and, on that occasion, he had it again almost as soon as it had gone; indeed, within the same second he was smiling at himself for having allowed himself to be disposed towards such crass folly.