The perspiration stood out heavily upon me. Fear gripped me, and I was helpless. Yet even in this supreme moment, even when this fiend of a woman fitted that horrible metal cap upon my head, I remembered the marks upon the dead chauffeur. He had been electrocuted as I was to be. It was the frame holding him in a sitting posture which had marked his body--it was this awful chair which had left those depressions on his arms. I was glad to know the truth. It was the ruling passion, strong in death. The woman crossed to the cupboard quickly. There was a click, the moving of the switch, and then--nothing. Thank God! Nothing. The cap gripped my head, that was all. The woman looked at me, and then rushed to the door, only to stagger backward as Christopher Quarles and Zena met her on the threshold. Their first thought was for me, and Mrs. Barrymore had the moment for which she had always been prepared, doubtless. The poison pilule had been concealed in a signet ring she wore, and in a few moments she was lying dead in that horrible Tudor room. That Mrs. Barrymore had invited me to come to tea on the following day, when there was no reason why I should not have stayed then, had aroused Zena's suspicions, and she had watched Mrs. Barrymore's every movement. Until then she knew nothing of the secret of the Tudor room, but she saw her employer go there and examine the cupboard. In the night Zena went and examined it, and destroyed the current by rendering the switch ineffective. Every day since Zena had been at Lantern House Quarles had met her in the grounds. Of course she had not gone to London that day, but had met her grandfather, and they had entered the house together, unseen. They would have been in time to prevent my going through that horrible ordeal had I not arrived an hour before I was expected. "You had no right to let Zena ran such a risk," I said to Quarles. "You ought not to have sent her to Lantern House to test your theories."