Upon that very couch I had reclined while the foul tragedy had been enacted in that room. My head swam; I closed my eyes. The great gilt clock, with its pendulum representing the figure of a girl swinging beneath the trees, standing on the mantelshelf, ticked out low and musically, just as it had done on that fateful night. In an instant, as I sat with head turned from my companions and my eyes shut, the whole of that tragic scene was re-enacted. I heard the crash, the woman's scream, the awe-stricken exclamation that followed in the inner room. I heard, too, the low swish of a woman's skirts, the heavy blow struck by an assassin's hand, and in horror felt the warm life-blood of the unknown victim as it trickled upon my hand. Mabel suddenly ran her white fingers over the keys, and the music brought me back to a realisation of my true position. I had at length discovered the actual house in which the mysterious tragedy had been enacted, and it became impressed upon me that by the exercise of greatest care I might further be enabled to prosecute secret investigations to a successful issue, and at length solve the enigma. My eyes fixed themselves upon the couch. It was the very spot where I had rested, sightless, helpless, while those strange events had taken place about me. Was it any wonder that I became filled with apprehensions, or that I sat there petrified as one turned to stone? The square, dark-green antimacassar had been placed in the exact centre of the couch, and sewed down in order to keep it in its place. Where I was sitting was fortunately in the shadow, and when Mabel commenced playing I rose--unsteadily I think--and reseated myself upon the couch, as being more comfortable. Then, while the woman who held me entranced played a selection from the "Trovatore," I, unnoticed by the others, succeeded in breaking the stitches which tacked the antimacassar to the brocade. The feat was a difficult one, for one does not care to be detected tearing the furniture of one's hostess. Nevertheless, after ten minutes or so I succeeded in loosening it, and then, as if by the natural movement of my body, commenced to work aside. The music ceased, and even though all my attention was now centred upon my investigations, I congratulated Mabel upon her accurate execution. Hickman was standing beside her, and together they began to search for some piece he had requested her to play, while Miss Wells, with her hearts and elephants jingling, turned to me and commenced to talk. By this I was, of course, interrupted; nevertheless, some ten minutes later, I rose, and naturally turned back to straighten the rumpled antimacassar. In doing so I managed to lift it and glance beneath. In an instant the truth was plain. Concealed beneath that square of green crochet-work was a large dark-brown stain upon the brocade. It was the mark of the life-blood of that thin, well-dressed, unknown victim, who had, in an instant, been struck to the heart!