As she thought this, half laughing, there came a sound from the next room--that room which might have been the grave of the strange woman who occupied it, so dead was the silence which reigned there day and night. Never before had Joan heard the least noise on the other side of the dividing wall, but now she was startled by a crash as of breaking glass, followed by the dull, soft thud which could only have been made by the fall of a human body. Joan sat up, her heart thumping, and it gave a frightened bound as a groan came brokenly to her ears. She waited no longer, but slipped her bare feet into a pair of satin _mules_, flung on her dressing-gown, and in another moment was out of her room and in the dark passage, fumbling for the handle of the other door. Mrs. Gone kept her door unlocked in the daytime, perhaps to save herself the trouble of rising to admit servants, or her only visitor, Joan Carthew; but the girl feared that it might not be so at night, and that before she could penetrate the mystery of the fall and the groan, the whole house would have to be disturbed. She was relieved, therefore, to find that the door yielded to her touch. Pushing it open, she listened for an instant, but only the dead silence throbbed in her ears. As she got into her dressing-gown, with characteristic presence of mind Joan had caught up a box of matches and put it into her pocket. The room was as dark as the passage outside, and the girl struck a match before crossing the threshold. The little flame leaped and brightened. Something on the floor glimmered white in the darkness, and Joan did not need to bend down to know what it was. The gas was close to the door, and she lighted it with the dying match, which burnt her fingers. Then she saw clearly what had happened. In tottering uncertainly across the floor, Mrs. Gone had knocked over a small table holding a china candlestick, a water-bottle, and a goblet. She had fallen, and after uttering that one groan which had crept to Joan’s ears, she had lost consciousness. The girl’s quick eyes sought for an explanation of the catastrophe. The long, white figure lay at some distance from the bed, and near the mantel. On the mantel stood a curiously shaped, dark green bottle, which Joan had once been requested to give to Mrs. Gone. She had seen a few drops of some colourless liquid poured into a wineglass of water; and when it had been swallowed, the ghastly pallor of the face had changed to a more natural tint. Mrs. Gone had then said that she took the medicine when very ill. If she used it oftener, its effect would disappear, and she would have nothing left to turn to at the worst. "It was that bottle she was trying to find in the dark," Joan guessed. "She must have been too ill to try and light the gas. Now, how much was it that I saw her pour out? It might have been ten drops--no more."