Inspector Whyland dismissed Mr. Houlder and the electricians, and went on into the cellar with the constable. “There’s something queer about this business, sir?” said the latter, as soon as they were alone. “I had a look round while I was waiting for you, and the first thing I saw was one of them white counters, same as the others had. There it lies, sir, I didn’t touch it.” They were in the cellar by now, and Whyland glanced at the counter, lying in the beam of light which the constable had thrown upon it. “With the figure IV on it, I’ll wager,” he muttered. “Yes, I thought so. We’ll try for finger marks, but I’ll bet it’s no good. Now, let’s have a look at this dead man.” The constable turned his lamp on the prostrate form, and Whyland knelt down and gazed at it intently. The body was lying doubled up as it had fallen, and was quite cold. “H’m,” said Whyland, rising to his feet. “We can’t do much more till the doctor comes. You don’t know who he is, I suppose?” “Mr. Houlder said he believed his name was Martin, sir,” replied the constable cautiously. “Well, you stay here till the doctor comes. I’ll go and have a chat with Houlder. Just throw your light over the floor for a minute. Hullo, what’s this?” He strode across the cellar and carefully picked up a small automatic. “Hasn’t been fired,” he muttered. “Now I wonder who that belongs to? Just see if you can spot anything else. Don’t touch it, if you do.” He went upstairs again, and drew Mr. Houlder aside into a quiet corner. Mr. Houlder’s story was a very simple one. His foreman had orders to leave the key to the house with Mr. Briggs, the confectioner, three doors off. Mr. Briggs was Houlder’s brother-in-law. The reason for this arrangement was that whoever came on the scene first could get the key and start work. On Saturday the key had been left as usual, about 12.30. On Saturday evening, about nine o’clock, Mr. Briggs had come to his place and told him that Mr. Lacey, who knew about the key arrangement, had rung him up to say that a Mr. Martin was coming to inspect the drains. Mr. Lacey was to have met him at two o’clock, but would be delayed. Would Mr. Briggs keep a lookout for him and give him the keys. Mr. Briggs had promised to do so, and his daughter Marjorie had seen Mr. Martin, who had promised to bring back the keys, but had not done so. Mr. Briggs had forgotten all about them until the evening, and then, finding that the door of Number 407 was securely locked, had supposed that Mr. Martin had gone away with the keys in his pocket. Mr. Houlder had agreed with this theory, and had given Mr. Briggs a duplicate key which he happened to have.