As they stood together on the narrow landing, Scar exclaimed—
“Here, I know. These are only openings through the thick walls to keep them dry.”
“Look!” said Fred, pointing before them at a thin pencil of light which made a spot on the wall.
“That’s sunshine,” cried Scarlett, “and shows what I said. This is one of the walls we are in, and that must be the south.”
“Why?” said Fred, trying to touch the slit through which the light came.
“Because the sun shines in. Let’s go on to the end.”
This was soon reached, for at the end of a dozen steps they came upon a narrow door studded with great nails, and after a little hesitation, Fred pushed this, and the boys started back at the hideous groan which greeted them.