Chudleigh Wilmot took the paper he wanted from the place where it had lain, and was about to close the doors of the cabinet once more--restoring them, until he could have the lock repaired, to their deceptive appearance of security--when his attention was caught by a dark-coloured spot, about the size of a shilling, upon the topmost sheet of a packet of papers which lay beside a small mahogany case containing the before-mentioned poisons. He took the packet out and examined it. The spot was there, and extended to every paper in the packet. A sudden flush and expression of vague alarm crossed Wilmot's face. He took up the case and examined the exterior. A dark mark, the stain of some glutinous fluid, ran down the side of the box next which the papers had lain. For a moment he held the case in his hands, and literally dared not open it. Then in sickening fear he did so, and found its contents apparently undisturbed. The box was divided into ten little compartments, in each of which stood a tiny bottle, glass-stoppered and covered with a leaden capsule. To the neck of each was appended a little leaden seal, the mark of the French chemist from whom Wilmot had purchased the deadly drugs. He took the bottles out one by one, examined their seals, and held them up to the light. All safe for nine out of the number; but as he touched the tenth, the capsule with the leaden seal attached to it fell off, and Wilmot discovered, with ineffable horror, that the bottle, which had contained one of the deadliest poisons known to science, was half empty. He set down the case, and reeled against the corner of the mantelshelf near him, like a drunken man. He could not face the idea that had taken possession of him; he could not collect his thoughts. He gasped as though water were surging round him. Once more he took up the bottle and looked at it. It was only too true; one half the contents was missing. He closed the case, and pushed it back into its place. It struck against something on the shelf of the cabinet. He felt for the object, and drew out _his wife's seal-ring!_ And now Chudleigh Wilmot knew what was the terror that had seized him. It was no longer vague; it stood before him clear, defined, unconquerable; and he groaned: "My God! she destroyed herself!" CHAPTER XIII. A Turn of the Screw. Chudleigh Wilmot had not seen Mrs. Prendergast since the day on which his wife's funeral had taken place; and it was with equal surprise and satisfaction that she received a brief but kindly-worded note from him, requesting her to permit him to call upon her.