"My darling," said Lady Lacy, "you are overdone, and it was foolish of you tearing upstairs and scrambling into your morning-gown. I have sent for Groves. Are you able now to rise? Can you manage to reach your room?" "My room!" she shuddered. "Let me lie here a little longer. I cannot walk. Let me be here till the doctor comes." "Certainly, dearest. I thought you looked very unlike yourself all day at the regatta. If you had felt out of sorts you ought not to have gone." "Auntie! I was quite well in the morning." Presently the medical man arrived, and was shown in. Betty saw that Lady Lacy purposed staying through the interview. Accordingly she said nothing to Dr. Groves about what she had seen. "She is overdone," said he. "The sooner you move her down to Devonshire the better. Someone had better be in her room to-night." "Yes," said Lady Lacy; "I had thought of that and have given orders. Martha can make up her bed on the sofa in the adjoining dressing-room or boudoir." This was a relief to Betty, who dreaded a return to her room--her room into which her other self had gone. "I will call again in the morning," said the medical man; "keep her in bed to-morrow, at all events till I have seen her." When he left, Betty found herself able to ascend the stairs. She cast a frightened glance about her room. The straw hat, the grey dress were there. No one was in it. She was helped to bed, and although laid in it with her head among the pillows, she could not sleep. Racking thoughts tortured her. What was the signification of that encounter? What of her strange sleeps? What of those mysterious appearances of herself, where she had not been? The theory that she had walked in her sleep was untenable. How was she to solve the riddle? That she was going out of her mind was no explanation. Only towards morning did she doze off. When Dr. Groves came, about eleven o'clock, Betty made a point of speaking to him alone, which was what she greatly desired. She said to him: "Oh! it has been worse this last occasion, far worse than before. I do not walk in my sleep. Whilst I am buried in slumber, someone else takes my place." "Whom do you mean? Surely not one of the maids?" "Oh, no. I met her on the stairs last night, that is what made me faint." "Whom did you meet?" "Myself--my double." "Nonsense, Miss Mountjoy." "But it is a fact. I saw myself as clearly as I see you now. I was going down into the hall." "You saw yourself! You saw your own pleasant, pretty face in a looking-glass." "There is no looking-glass on the staircase. Besides, I was in my alpaca morning-gown, and my double had on my pearl-grey cloth costume, with my straw hat. She was mounting as I was descending." "Tell me the story."