"It may not have anything to do with anything," Tarzan admitted, "but it suggests possibilities."
"What possibilities?" she demanded.
"A way out. The fresh air comes in from that other room through the bars of that door; it has to go out somewhere. The draft is so strong that it suggests a rather large opening. Do you see any large opening in this room through which the air could escape."
The girl rose to her feet. She was commencing to understand the drift of his remarks. "No," she said, "I see no opening."
"Neither do I; but there must be one, and we know that it must be some place that we cannot see." He spoke in a whisper.
"Yes, that is right."
"And the only part of this room that we can't see plainly is among the dark shadows on the ceiling over in that far corner. Also, I have felt the air current moving in that direction."
He walked over to the part of the room he had indicated and looked up into the darkness. The girl came and stood beside him, also peering upward.
"Do you see anything?" she asked, her voice barely audible.
"It is very dark," he replied, "but I think that I do see something—a little patch that appears darker than the rest, as though it had depth."