He went into the house ahead of his companion, pointed out the room where the murder was committed, “as I feel perfectly sure,” he added; and then led the way up the narrow stairs into what had been Captain Attymar’s sitting-room. “If you sit at that table you’ll see the plan of the house, and I may show you one or two very interesting things.” Mr. Reeder switched on a handlamp on the table and Clive Desboyne sat down, and followed, apparently entranced, the recital of J.G. Reeder’s theory. “If you have time--what is the time?” Clive Desboyne looked up at the ceiling, stared at it for a while. “Let me guess,” he said slowly. “Four o’clock.” “Marvellous,” murmured Mr. Reeder. “It is within one minute. How curious you should look up at the ceiling! There used to be a clock there.” “In the ceiling?” asked the other incredulously. He rose, walked to the window and stared out on to the wharf. From where he stood he could see the policeman on duty at the gate. There was nobody watching at a little door in the ragged fence which led to Shadwick Passage. Suddenly Mr. Clive Desboyne pointed to the wharf. “That is where the murder was committed,” he said quietly. Mr. Reeder took a step towards the window and cautiously craned his neck forward. He did not feel the impact of the rubber truncheon that crashed against the base of his skull, but went down in a heap. Clive Desboyne looked round, walked to the door and listened, then stepped out, locked the door, came down the stairs and on to the wharf. The policeman eyed him suspiciously, but Mr. Desboyne turned and carried on a conversation with the invisible Reeder. He strolled round to the front of the house. Nobody saw him open the little gate into the passage. The end of Shadwick Lane was barred, but Gaylor did not remember the passage until too late. It was he who found Reeder and brought him back to consciousness. “I deserve that,” said Mr. Reeder when he became articulate. “Twice in one day! I am getting too old for this work.” CHAPTER X One of those amazing things which so rarely happen, that fifty-thousand-to-one-against chance, had materialized, and the high chiefs of Scotland Yard grew apoplectic as they asked the why and the wherefore. A man wanted by the police on a charge of murder had walked through a most elaborate cordon. River police had shut off the waterway; detectives and uniform men had formed a circle through which it was impossible to escape; yet the wanted man had, by the oddest chance, passed between two detectives who had mistaken him for somebody they knew. Whilst Reeder was waiting at Scotland Yard he explained in greater detail the genesis of his suspicion.