The change of scene from the dark horror of the narrow ledge and its abyss below to the dust-covered room with its modern furniture was striking and extraordinary.
"Now step carefully," said Job.
The captain, who had practiced that maneuver, obeyed, and the two men cleared as narrow a strip of dust as possible.
"That will be all right when we come back," said Job.
As he spoke he diverted the captain's attention for a moment, and in that moment touched the spring of the opposite bookcase.
The bookcase drew back, and a gust of air, damp and chilly, rose from the aperture.
It was that chilly, moist atmosphere which the captain had noticed when the ghost disappeared.
"Subterranean," he said.
"Ay," said Job.
He threw the light down the dark deep hole.