"No, sir. I watched that Miss Katherine didn't leave the library, but I think she must have caught Mr. Silas in the upper hall after he had pretended to give up and had persuaded his brother to spend the night." Paredes smiled whimsically. He took two faded photographs from his pocket. They were of young men, after the fashion of Blackburns, remarkably alike even without the gray, obliterating marks of old age. "I found these in the family album," he said. "We should have known the difference just the same," the doctor grumbled. "Why didn't we know the difference?" "I've complained often enough," Paredes smiled, "of the necessity of using candles in this house. There was never more than one candle in the old bedroom. There were only two when we looked at the murdered man in his coffin. And in death there are no familiar facial expressions, no eccentricities of speech. So you can imagine my feelings when I tried to picture the drama that had gone on in that room. You can imagine poor Maria's. Which one? And Maria didn't know about the panel, or the use of Miss Katherine's hat-pin, or the handkerchief. All of those details indicated Silas Blackburn." "How could my handkerchief indicate anything of the kind?" Bobby asked, "How did it come there?" "What," Paredes said, "is the commonest form of borrowing in the world, particularly in a climate where people have frequent colds? I found a number of your handkerchiefs in your grandfather's bureau. The handkerchief furnished me with an important clue. It explains, I think, Jenkins will tell you, the moving of the body. It was obviously the cause of Howells's death." "Yes, sir," Jenkins quavered. "Mr. Silas thought he had dropped his own handkerchief in the room with the body. I don't know how you've found these things out." "By adding two and two," Paredes laughed. "In the first place, you must all realize that we might have had no mystery at all if it hadn't been for Miss Katherine. For I don't know that Maria could have done much in a legal way. Silas Blackburn had intended to dispose of the body immediately, but Miss Katherine heard the panel move and ran to the corridor. She made Jenkins break down the door, and she sent for the police. Silas Blackburn was helpless. He was beaten at that moment, but he did the best he could. He went to Waters, hoping, at the worst, to establish an alibi through the book-worm who probably wouldn't remember the exact hour of his arrival. Waters's house offered him, too, a strategic advantage. You heard him say the spare room was on the ground floor. You heard him add that he refused to open his door, either asking to be left alone or failing to answer at all. And he had to return to the Cedars the next day, for he missed his handkerchief, and he pictured himself, since he thought it was his own, in the electric chair. I'm right, Jenkins?"