The Professor told his story as simply as possible, outlining his actions and repeating the Black Sailor’s story, up to the moment when it had occurred to him that his only chance of escape was to produce an explosion. “It could not make things any worse, as far as I was concerned,” he said. “I was bound to be overcome by the gas in a very few minutes. But I had to wait until I judged the mixture of gas and air to be correct, and I was very doubtful whether this would take place before I became unconscious. I guessed that I should feel the force of the explosion least by lying on the floor, and, as it proved, that saved me. Morlandson, who was standing up when the explosion took place, bore the full brunt of it, and it killed him.” “Well, it’s a most extraordinary case altogether,” replied Hanslet, as the Professor concluded his account. “This man Morlandson, or Ludgrove as we called him, displayed the most amazing ingenuity, and there was no reason why we should ever have suspected him, any more than we suspected anybody else in the neighbourhood. And the way he gradually concentrated our attention on poor Copperdock was masterly. “No doubt you will like to hear our side of the story. It’s fairly simple. About ten minutes before midnight the constable on duty outside Ludgrove’s shop heard a terrific crash and a noise of breaking glass. He hammered at the door, and, getting no reply, had the sense to make his way round to the back, eventually reaching the place by much the same route as the Black Sailor used, according to what you have just told me. He found the window blown out of the back room, a terrible mess inside, and a jet of burning gas coming out of the broken bracket. He blew his whistle, and by the time that two or three of our fellows had got inside, you came to, Professor. “Of course, when I heard that you had identified the dead man as Dr. Morlandson, I thought you were still dizzy with the shock. We couldn’t make out who he was; he was dressed as a sailor, but we couldn’t recognize his face, black and with all the hair burnt off. It couldn’t be Ludgrove, yet, if it wasn’t, what had become of the old herbalist? “We next set to work to search the house. The first thing we found, lying on the dressing table, was a most interesting document, which I should like you to read, Professor. It was in a sealed envelope, addressed ‘To all whom it may concern.’” Hanslet produced a sheet of paper, covered with writing which the Professor recognized as being the same as that of the letter which Ludgrove had sent him. He beckoned to Harold, who had been listening from the further end of the room. “Read that to me, my boy,” he said. Harold took the paper and opened it. It contained no heading, but started abruptly.