Colwyn approached the head of the bed and bent down to examine the bedposts. A slight groove in the deep pile carpet showed clearly enough that the bed had been pushed back a few inches. The change in position was so trifling that it might have been attributed to the act of a servant in sweeping the room if a closer examination had not revealed the continuance of the groove under the bed. The inference was unmistakable: the bed, in the first instance, had been pushed much farther back on its castors, and then almost, but not quite, restored to its original position. Had the bed been moved to gain access to the fireplace? He could see no reason for such a proceeding. It was too early in the autumn to need fires, and the room had not been occupied since the murder. In any case, the appearance of the grate showed that no fire had been lit. There was ample space to pass between the head of the bed and the fireplace, though perhaps not much room for movement. On his last visit Colwyn had looked into this space to test its possibilities of concealment. In the quickened interest of his new discovery he pushed the bed out of the way and examined it again. The first thing that caught his eye was a scratch on the polished surface of the register grate. It looked to be of recent origin, and for that reason suggested to Colwyn's mind that the bed had been moved by somebody who wanted more room in front of the grate. For what purpose? He turned his attention to the grate itself in the hope of obtaining an answer to that question. The grate was empty, and in the housewifely way a sheet of white paper had been laid on the bottom bars to catch occasional flakes of soot from the chimney. But there were no burnt papers or charred fragments to suggest that the grate had recently been used. Dissatisfied and perplexed, Colwyn was about to rise to his feet when it chanced that his eyes, glancing into a corner, lighted on something tiny and metallic in the crevice between the white paper and the side bars of the grate. Wondering what it was, he succeeded in getting it out with his finger and thumb. It was a percussion cap.