"The report did not come at the moment I anticipated, but I was not perturbed at the delay. My experiments had taught me the difficulty of fixing an explosion for an exact period. The time was in general approximately the same, but there were reasons which caused a slight difference. The wick always burnt at a uniform rate; the trouble was with the string. Sometimes it was slow in catching. Sometimes the pressure of the string partly extinguished the wick and made combustion slower as it neared the point of contact. Once I tied the string so tight that the wick went out altogether just before reaching the string. But I had taken measures to overcome these little irregularities, and to make sure of the string catching readily I had rubbed a little petrol on it where it crossed the wick. "But it was the scream before the report which upset my calculations and almost caused me to collapse. When that terrible cry rang out my false strength fled from me, leaving me weak and trembling. I think I should have betrayed myself if the report had not followed so quickly, throwing everybody into the same state of confusion as myself. I do not know how I managed to make my limbs carry me upstairs with the others. I did not know what had happened. My brain refused to act. I was conscious of nothing except that a great wheel seemed turning inside my head, tightening all my nerves to such taut agony that I could hardly refrain from crying aloud. "What I said or did when I found myself in the bedroom I do not know. When I saw that everything was as I had arranged my mind began swinging like a pendulum towards my revenge, and I struggled to lead the search towards the staircase. But I was unable to move. I was like a man in a dream, encompassed by invisible obstacles. Then the wheel in my head suddenly relaxed, I felt the room and its objects slipping from me, and everything went black. "You know about my illness. It was not until I was supposed to be recovering that the power of clear thought came back to me. There were days when my brain was numb and powerless, like that of one newly awakened from a terrible nightmare, striving to recall what had happened. Then one day the veil was drawn, and I remembered everything. My aunt was in the room, and I questioned her. She brought Musard to me, and from him I learnt the truth. "Intuitively I realized what had happened. Hazel Rath had gone to the room for some unknown reason, had seen my wife lying there, and screamed. Then, hardly conscious of what she was doing, she picked up the revolver I had left lying by the bedside, and ran out of the room in fright. I was even able to divine a reason for her silence under the accusation of murder. She felt that nobody would believe her story, especially after the history of her mother's past was brought to light.