slight one; but in such a case as this no fact, however insignificant, is unimportant, and the most slender circumstance may, if rigorously followed up, ultimately lead to results wholly unlooked for and disproportionate to it. "Here, then, is a splendid opportunity for our detectives to cover themselves with glory, and, by the capture of the perpetrator, to prevent this--one of the most terrible crimes of recent days--from being relegated to the already too well-filled limbo of unfathomable mysteries." THE STORY THE FIRST SCENE: AT CASTERWELL.