There came then an interval in the conversation that was very significant. It did not seem a real pause, or the silence real silence, for both men continued to think so rapidly and strongly that one almost imagined their thoughts clothed themselves in words in the air of the room. I was more than a little keyed up with the strange excitement of all I had heard, but what stimulated my nerves more than anything else was the obvious fact that the doctor was clearly upon the trail of discovery. In his mind at that moment, I believe, he had already solved the nature of this perplexing psychical problem. His face was like a mask, and he employed the absolute minimum of gesture and words. All his energies were directed inwards, and by those incalculable methods and processes he had mastered with such infinite patience and study, I felt sure he was already in touch with the forces behind these singular phenomena and laying his deep plans for bringing them into the open, and then effectively dealing with them.
Colonel Wragge meanwhile grew more and more fidgety. From time to time he turned towards my companion, as though about to speak, yet always changing his mind at the last moment. Once he went over and opened the door suddenly, apparently to see if any one were listening at the keyhole, for he disappeared a moment between the two doors, and I then heard him open the outer one. He stood there for some seconds and made a noise as though he were sniffing the air like a dog. Then he closed both doors cautiously and came back to the fireplace. A strange excitement seemed growing upon him. Evidently he was trying to make up his mind to say something that he found it difficult to say. And John Silence, as I rightly judged, was waiting patiently for him to choose his own opportunity and his own way of saying it. At last he turned and faced us, squaring his great shoulders, and stiffening perceptibly.
Dr. Silence looked up sympathetically.
“Your own experiences help me most,” he observed quietly.
“The fact is,” the Colonel said, speaking very low, “this past week there have been outbreaks of fire in the house itself. Three separate outbreaks—and all—in my sister’s room.”
“Yes,” the doctor said, as if this was just what he had expected to hear.
“Utterly unaccountable—all of them,” added the other, and then sat down. I began to understand something of the reason of his excitement. He was realising at last that the “natural” explanation he had held to all along was becoming impossible, and he hated it. It made him angry.
“Fortunately,” he went on, “she was out each time and does not know. But I have made her sleep now in a room on the ground floor.”
“A wise precaution,” the doctor said simply. He asked one or two questions. The fires had started in the curtains—once by the window and once by the bed. The third time smoke had been discovered by the maid coming from the cupboard, and it was found that Miss Wragge’s clothes hanging on the hooks were smouldering. The doctor listened attentively, but made no comment.
“And now can you tell me,” he said presently, “what your own feeling about it is—your general impression?”