Crossing the room, he closed and locked the study door, then, returning, he sat down once more, entirely, master of himself. Frowning slightly he looked from Harley in my direction, and then back again at Harley. “Gentlemen,” he resumed, “I appreciate the urgency of my danger. Preposterous though I know it to be, nevertheless it is perhaps no more than natural that suspicion should fall upon me.” He was evidently thinking rapidly. His manner had grown quite cool, and I could see that he had focussed his keen brain upon the abyss which he perceived to lie in his path. “Before I commit myself to any statements which might be used as evidence,” he said, “doubtless, Mr. Harley, you will inform me of your exact standpoint in this matter. Do you represent the late Colonel Menendez, do you represent the law, or may I regard you as a perfectly impartial enquirer?” “You may regard me, Mr. Camber, as one to whom nothing but the truth is of the slightest interest. I was requested by the late Colonel Menendez to visit Cray’s Folly.” “Professionally?” “To endeavour to trace the origin of certain occurrences which had led him to believe his life to be in danger.” Harley paused, staring hard at Colin Camber. “Since I recognize myself to be standing in the position of a suspect,” said the latter, “it is perhaps unfair to request you to acquaint me with the nature of these occurrences?” “The one, sir,” replied Paul Harley, “which most intimately concerns yourself is this: Almost exactly a month ago the wing of a bat was nailed to the door of Cray’s Folly.” “What?” exclaimed Colin Camber, leaning forward eagerly--“the wing of a bat? What kind of bat?” “Of a South American Vampire Bat.” The effect of those words was curious. If any doubt respecting Camber’s innocence had remained with me at this time I think his expression as he leaned forward across the desk must certainly have removed it. That the man was intellectually unusual, and intensely difficult to understand, must have been apparent to the most superficial observer, but I found it hard to believe that these moods of his were simulated. At the words “A South American Vampire Bat” the enthusiasm of the specialist leapt into his eyes. Personal danger was forgotten. Harley had trenched upon his particular territory, and I knew that if Colin Camber had actually killed Colonel Menendez, then it had been the act of a maniac. No man newly come from so bloody a deed could have acted as Camber acted now. “It is the death-sign of Voodoo!” he exclaimed, excitedly. Yet again he arose, and crossing to one of the many cabinets which were in the room, he pulled open a drawer and took out a shallow tray.