“It was the crowning piece of evidence, Knox, evidence of such fiendish cleverness on the part of those who had plotted Menendez’s death that I began to wonder whether after all it would be possible to defeat them. I realized that Camber’s life hung upon a hair. For the production of that rifle before a jury of twelve moderately stupid men and true could not fail to carry enormous weight. Whereas the delicate point upon which my counter case rested might be more difficult to demonstrate in court. To-night, however, we shall put it to the test, and there are means, no doubt, which will occur to me later, of making its significance evident to one not acquainted with the locality. The press photographs, which I understand have been taken, may possibly help us in this.” Bewildered by my friend’s revolutionary ideas, which explained the hitherto mysterious nature of his enquiries, I scarcely knew what to say; but: “If it’s a frame-up, Mr. Harley,” said Wessex, “and the more I think about it the more it has that look to me, practically speaking, we have not yet started on the search for the murderer.” “We have not,” replied Harley, grimly. “But I have a dawning idea of a method by which we shall be enabled to narrow down this enquiry.” It must be unnecessary for me to speak of the state of suppressed excitement in which we passed the remainder of that afternoon and evening. Dr. Rolleston called again to see Madame de Stämer, and reported that she was quite calm. In fact, he almost echoed Val Beverley’s words spoken earlier in the day. “She is unnaturally calm, Mr. Knox,” he said in confidence. “I understand that the dead man was a cousin, but I almost suspect that she was madly in love with him.” I nodded shortly, admiring his acute intelligence. “I think you are right, doctor,” I replied, “and if it is so, her amazing fortitude is all the more admirable.” “Admirable?” he echoed. “As I said before, she has the courage of ten men.” A formal dinner was out of the question, of course; indeed, no one attempted to dress. Val Beverley excused herself, saying that she would dine in Madame’s room, and Harley, Wessex, and I, partook of wine and sandwiches in the library. Inspector Aylesbury arrived about eight o’clock in a mood of repressed irritation. Pedro showed him in to where the three of us were seated, and: “Good evening, gentlemen,” said he, “here I am, as arranged, but as I am up to my eyes in work on the case, I will ask you, Mr. Harley, to carry out this experiment of yours as quickly as possible.” “No time shall be lost,” replied my friend, quietly. “May I request you to accompany Detective-Inspector Wessex and Mr. Knox to the Guest House by the high road? Do not needlessly alarm Mrs. Camber. Indeed, I think you might confine your attention to Mrs. Powis. Merely request permission to walk down the garden to the hut, and be good enough to wait there until I join you, which will be in a few minutes after your arrival.”