In many a case of night terrors, no great psychological skill is required to detect the influence of emotional stress as the prime factor in causing the alarming attacks. In one instance that has come to my knowledge, a seven-year-old girl was brought to a physician, with a history of both night and day terrors. She was subject, her mother said, to attacks of loud screaming, during which she seemed dazed and in an agony of fear. The attacks sometimes lasted ten minutes, and immediately afterwards the girl generally fell into a heavy sleep. Her night terrors were of the usual sort, except that on the occasion of the first attack she was in such a panic that she opened her bedroom window and threw herself out of it. Luckily, it was early evening, and her mother, walking in the garden beneath her window, was able to catch her and save her from harm. "She had gone to bed as usual," the mother said, in detailing this episode, "and seemed to be quite well, though I remember I thought she looked a little wild about the eyes. For an hour she slept quietly. Then, as I later learned, she woke up moaning, jumped out of bed, and made for the window." "And," asked the physician to whom the child had been taken, "had anything out of the way occurred to her that day?" "Nothing." "Are you sure of that?" "Well, nothing of real account, at all events. I have been told that somebody jokingly said to her that if she were not a good girl a black man would come to her room and carry her off. But this did not seem to disturb her much at the time." Hereupon, the situation became clear to the physician. It was evident that, subconsciously if not consciously, the thought of the supposed danger, acting on a mind none too well organised by inheritance--there was epilepsy in the family--had acquired sufficient force to bring on the attack of nocturnal panic and the subsequent attacks of day and night terrors. Probably, moreover, this was not the first time that statements of a fear-inspiring character had been made to the child, so that this last "joke" might well serve to agitate her excessively. Compare with this the case of a four-year-old boy, whose night terrors were accompanied by a strange hallucination that he saw the devil, and that the devil was trying to catch him. Every night for several weeks he would wake after one or two hours of sleep, would leap from bed with a shriek, and run wildly around the room, calling on his mother to save him and to drive the devil out of the house.