“I was asking whether it was credible that some one should have laid two sets of quite inconsistent false clues for the purpose of misleading us.” “Two sets of clues, dear. And both to mislead you. It must be very difficult to see through them both.” “By George,” exclaimed the superintendent, leaping from his chair and beginning to pace up and down the room. “By George, you’ve given me just the idea I wanted. Yes, that must be it.” “What must be what, dear? I had no idea I’d said anything clever.” “Why, _both_ sets of clues weren’t meant to mislead us. That’s it. The criminal laid two sets of false clues. He meant us to see through one set; but he thought we should never see through the other. He reckoned it would never occur to us that both sets of clues were false. Oh, yes. We were to feel awfully bucked up about seeing through the first set of clues—the obviously false ones—and then we were meant to go on and hang the wrong man gaily on the strength of the others. It was a clever idea, too, by Jove.” “Do you mean——” Mrs. Wilson began; but her husband was now in full flow, and he cut her short. “What I mean is that the criminal deliberately laid the set of clues which pointed to the two men having murdered each other. We were bound to see through these, because the conclusion to which they pointed was just physically impossible. Then he laid the clues pointing to Walter Brooklyn, really meaning this time to get Walter Brooklyn hanged for the murders. My word, yes, this does throw a new light on the case. My dear, you’ve done it again. There’s lots to find out yet; but I’m sure it will come out right now that I know where to begin.” “Then who was the murderer, dear? Have I told you somehow? I’m sure I don’t know who it was.” “Neither do I, my dear. But I think I do know now how to begin looking for him. When I’ve found him I’ll tell you who he is. And half the credit of finding him will be yours.” The superintendent was so moved that he went up and kissed his wife as he kissed her only on occasions of rare exaltation. Then he got back to business with a sigh. “If both sets of clues are false, my dear, you see that doesn’t make them valueless. They may still be used to point to the real murderer. Yes, I begin to see light already. If Walter Brooklyn did not send that telephone message, who did? Not much help there, I’m afraid, except that it was a very daring criminal indeed, and probably one who knew intimately both Walter Brooklyn and Liskeard House. Ringing up Brooklyn’s club shows that—he knew the man’s habits. There is something to go upon at all events. But there’s the walking-stick too—yes, that may be the point on which the whole case turns.” By this time Superintendent Wilson was talking to himself, almost oblivious of his listener. His wife knew too well to interrupt him. She resumed her knitting, only looking up at him from time to time as he paced up and down the room.