"I think you must have read of that, sir," replied Brewster, endeavouring to implicate first Miss Whitmarsh and then Parkinson in his meaning smile. "However, this is straightforward enough." "Then, of course, you have not thought it worth while to look for anything else?" "I have noted all the facts that have any bearing on the case. Were you referring to any particular point, sir?" "I was only wondering," suggested Carrados, with apologetic mildness, "whether you, or anyone, had happened to find a wad lying about anywhere." The sergeant stroked his well-kept moustache to hide the smile that insisted, however, on escaping through his eyes. "Scarcely, sir," he replied, with fine irony. "Bulleted revolver cartridges contain no wad. You are thinking of a shot-gun, sir." "Oh," said Carrados, bending over the spent cartridge he was examining, "that settles it, of course." "I think so, sir," assented the sergeant, courteously but with a quiet enjoyment of the situation. "Well, miss, I'll be getting back now. I think I have everything I want." "You will excuse me a few minutes?" said Miss Whitmarsh, and the two callers were left alone. "Parkinson," said Carrados softly, as the door closed, "look round on the floor. There is no wad lying within sight?" "No, sir." "Then take the lamp and look behind things. But if you find one don't disturb it." For a minute strange and gigantic shadows chased one another across the ceiling as Parkinson moved the table-lamp to and fro behind the furniture. The man to whom blazing sunlight and the deepest shade were as one sat with his eyes fixed tranquilly on the unseen wall before him. "There is a little pellet of paper here behind the couch, sir," announced Parkinson. "Then put the lamp back." Together they drew the cumbrous old piece of furniture from the wall and Carrados went behind. On hands and knees, with his face almost to the floor, he appeared to be studying even the dust that lay there. Then with a light, unerring touch he carefully picked up the thing that Parkinson had found. Very gently he unrolled it, using his long, delicate fingers so skilfully that even at the end the particles of dust still clung here and there to the surface of the paper. "What do you make of it, Parkinson?" Parkinson submitted it to the judgment of a single sense. "A cigarette-paper to all appearance, sir. I can't say it's a kind that I've had experience of. It doesn't seem to have any distinct watermark but there is a half-inch of glossy paper along one edge." "Amber-tipped. Yes?" "Another edge is a little uneven; it appears to have been cut." "This edge opposite the mouthpiece. Yes, yes." "Patches are blackened, and little holes--like pinpricks--burned through. In places it is scorched brown." "Anything else?" "I hope there is nothing I have failed to observe, sir," said Parkinson, after a pause. Carrados's reply was a strangely irrelevant question. "What is the ceiling made of?" he demanded.