“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.”