“Now for the theory,” he said. “There is a very steep hill in Beltonborough with a sharp, dangerous corner just outside the prison gate. Practically at the moment when James Rolls was being taken to the scaffold, Frank came tearing down this hill on his bicycle to catch an early train to town. He skidded and fell just outside the prison, and sustained compound fracture of his right arm. It was important that he should be moved as little as possible, and they carried him straight into the prison infirmary, where chloroform was administered and the prison surgeon set his arm. It was a very bad fracture, and he was under the anæsthetic for a considerable time. And when he came round, he was changed.... It seemed as if another spirit had taken possession of his body. He was not the same person: from being a charming boy, he had become something hellish.” Roupert sat up again and looked at me. “There is a theory,” he said, “that in certain conditions, such as deep mesmeric trance, or under the stupefaction of some complete anæsthetic, the bonds that seem so indissolubly to unite a man’s spirit to his mind and his body are strangely loosened. The condition approaches to that of temporary death: often under an anæsthetic the beat of the heart is nearly suspended, often the breathing is nearly suspended, and this happened to Frank under chloroform that morning. The connexion between his spirit and his body was loosened.... “There is another theory which you must consider also. It is proved, I think, beyond all doubt, that at the moment of death, particularly of sudden and violent death, the spirit, though severed from the body which it has inhabited, does not at once leave its vicinity, but remains hovering near to its discarded tenement, from which it has been expelled. Well, at that hour when Frank’s spirit was maintaining but a relaxed hold on his body, another spirit, violent and strong, was close at hand--a spirit that had just been disembodied.... And I believe the spirit of James Rolls entered and took possession.” I felt then what I have felt before and since, namely, some stir of horror in my head that made my hair move. You can often see it in dogs (I had seen it to-night in Fifi) when terror or rage erects their hackles. But the experience was only momentary, and the flame of this thing, its awful and burning quality, licked hotly round me.... “And how is Reid to help?” I asked.