Underneath was an opening in the wall, much less in width than the picture, yet ample for the passage of a crouched body.

The arm of the sofa made egress comparatively easy, while the frame of the picture, though appearing heavy and substantial, was in reality of light wood, and presented no obstacle to an active man.

The passage was black, and I thrust my head and shoulders in, striving to discern something of its nature.

For possibly three feet I could trace the floor, but beyond that point it seemed to disappear into impenetrable darkness.

This line of change was so distinct that I surmised at once it marked a descent to a lower level, either by ladder or stairs.