“I don’t,” was the reply. “When I came on duty Mr. Manford was up there in his private laboratory. Soon afterwards a friend of his--a foreign gentleman of the name of Bilsky--came to see him. I took him up, and then Mr. Manford said he had some business to do, and after that he had got a longish job to do and would be working late. So he said I might turn in and he would let me know when he had finished. And he did let me know with a vengeance, poor chap! I lay down in my clothes, and I hadn’t been asleep above a couple of hours when some noise woke me up. Then there came a most almighty bang. I rushed for an extinguisher and ran upstairs, and there I found the big laboratory all ablaze, the windows blown out and the ceiling down. But it wasn’t so bad as it looked. There wasn’t very much stuff up there; only the experimental stuff, and that burned out almost at once. I got the rest of the fire out in a few minutes.” “What stuff is it that you are speaking of?” the inspector asked. “Celluloid, mostly, I think,” replied the watchman. “They make films and other celluloid goods in the works. But Mr. Manford used to do experiments in the material up in his laboratory. This time he was working with alloys, melting them on the gas furnace. Dangerous thing to do with all that inflammable stuff about. I don’t know what there was up there, exactly. Some of it was celluloid, I could see by the way it burned, but the Lord knows what it was that exploded. Some of the raw stuff, perhaps.” At this point we reached the top floor, where a door blown off its hinges and a litter of charred wood fragments filled the landing. Passing through the yawning doorway, we entered the laboratory and looked on a hideous scene of devastation. The windows were mere holes, the ceiling a gaping space fringed with black and ragged lathing, through which the damaged roof was visible by the light of the watchman’s powerful lantern. The floor was covered with the fallen plaster and fragments of blackened woodwork, but its own boards were only slightly burnt in places, owing, no doubt, to their being fastened directly to the concrete which formed the actual floor. “You spoke of some human remains,” said the inspector. “Ah!” said the watchman, “you may well say ‘remains.’ Just come here.” He led the way over the rubbish to a corner of the laboratory, where he halted and threw the light of his lantern down on a brownish, dusty, globular object that lay on the floor half buried in plaster. “That’s all that’s left of poor Mr. Manford; that and a few other odd pieces. I saw a hand over the other side.”