Slowly the evening wore itself away, the presence of the silent-watching constabulary in the house making all friendliness between hosts and unwanted guests a matter of impossibility. Women and men drew together in little knots, discussing the affair in low-pitched voices, and even Maud Duggan's eyes held something of accusation now when they dwelt upon Cleek's face, so that at length he took Mr. Narkom by the arm and drew him toward the door. "Come, old friend," he said quietly. "We are intruders here, you and I. These other poor folk cannot be at rest in our presence. Come along to the library once more, and have a look about it. The place draws me, I must say. For I still believe that the secret of the whole terrible thing lies there. To-morrow afternoon is to be Coroner's Inquest--a hateful proceeding, to say the least of it--and I've given myself just that time to solve the mystery." "Cinnamon! And you don't imagine you're going to, do you, Cleek?" returned Mr. Narkom excitedly, as they passed down the passage together and entered the room. "That's rather a tall order, I must say. Seems as if we'd scoured this room from end to end." "And yet, from what I heard from Master Cyril a short while ago, that is exactly what we have _not_ done," rejoined Cleek, dropping to his knees and examining the wall plug which had interested him before. Meanwhile, Mr. Narkom strolled to the other side of the room, leaned against the spinning wheel in an attitude of ease, and then ... as Cleek's fingers began to trace an invisible path along the edge of the carpet, the Superintendent gave out a sudden little cry and jumped as though he had been shot. "Eh?--what's the matter, old friend?" Cleek was on his feet in an instant, for the Superintendent had gone a little pale, and was running his hands up and down his back in a curious fashion. "Pins and needles! Funniest sensation I've ever come across. Brrh! Just like a slight electric shock." Electric shock! Cleek was beside him in an instant, his face suddenly alight, and his hands searching over the instrument, here, there, and everywhere. Electric shock, eh? That was peculiar, to say the least of it. Then he stopped suddenly and sucked in his breath, and, whipping round upon his heel, clapped the Superintendent upon the shoulder. "And it takes _you_, after all, to lead us to the actual secret!" he said affectionately, smiling into Mr. Narkom's astonished face. "For here's the thing in a nutshell. What a blind fool I've been all the time, old friend. Here's the murderer, the perpetrator of last night's crime--the mechanical means of doing away with human life in such a perplexing manner. Here--right here. See?"