“Perhaps they are. Now shall we see if we can match them once more? I believe we can.” Whistling faintly, and very white in the face, Trent opened another small squat bottle containing a dense black powder. “Lamp-black,” he explained. “Hold a bit of paper in your hand for a second or two, and this little chap will show you the pattern of your fingers.” He carefully took up with a pair of tweezers one of the leaves cut from his diary, and held it out for the other to examine. No marks appeared on the leaf. He tilted some of the powder out upon one surface of the paper, then, turning it over, upon the other; then shook the leaf gently to rid it of the loose powder. He held it out to Mr. Cupples in silence. On one side of the paper appeared unmistakably, clearly printed in black, the same two finger-prints that he had already seen on the bowl and on the photographic plate. He took up the bowl and compared them. Trent turned the paper over, and on the other side was a bold black replica of the thumb-mark that was printed in grey on the glass in his hand. “Same man, you see,” Trent said with a short laugh. “I felt that it must be so, and now I know.” He walked to the window and looked out. “Now I know,” he repeated in a low voice, as if to himself. His tone was bitter. Mr. Cupples, understanding nothing, stared at his motionless back for a few moments. “I am still completely in the dark,” he ventured presently. “I have often heard of this fingerprint business, and wondered how the police went to work about it. It is of extraordinary interest to me, but upon my life I cannot see how in this case Manderson’s fingerprints are going—” “I am very sorry, Cupples,” Trent broke in upon his meditative speech with a swift return to the table. “When I began this investigation I meant to take you with me every step of the way. You mustn’t think I have any doubts about your discretion if I say now that I must hold my tongue about the whole thing, at least for a time. I will tell you this: I have come upon a fact that looks too much like having very painful consequences if it is discovered by any one else.” He looked at the other with a hard and darkened face, and struck the table with his hand. “It is terrible for me here and now. Up to this moment I was hoping against hope that I was wrong about the fact. I may still be wrong in the surmise that I base upon that fact. There is only one way of finding out that is open to me, and I must nerve myself to take it.” He smiled suddenly at Mr. Cupples’s face of consternation. “All right—I’m not going to be tragic any more, and I’ll tell you all about it when I can. Look here, I’m not half through my game with the powder-bottles yet.” He drew one of the defamed chairs to the table and sat down to test the broad ivory blade of the paper knife. Mr. Cupples, swallowing his amazement, bent forward in an attitude of deep interest and handed Trent the bottle of lamp-black. Chapter X. The Wife of Dives