It was not until Mr. Henley had made another and longer visit to the dark room that he became convinced beyond all doubt that the work of sealing up the place had been done from within, and that there was, and had been, no other outlet but that through which he had entered. To suppose that the main wall of the house had been closed in at a later period would be preposterous, and for manifest reasons. His examination of the room’s interior had been most thorough and exhaustive. The place was smoothly plastered upon the inside, and even the mason’s trowel had been found upon the floor within, so that it became at once evident that those who had done the work had been self-immured. Although the reason for such an act was utterly beyond his comprehension, Paul felt a certain satisfaction in ha
