“I’m afraid that draft was an imaginary one,” he said as he came back to Jack’s side. “I can find nothing which looks like an opening of any sort.”
“Then I guess it’s up to us to wait till they make their next move,” Jack sighed.
“But the air seems perfectly fresh in here,” Bob said as he sat down on the ground.
“I hadn’t thought of it before but that’s right. There must be some way for air to get in or it would begin to be stuffy.”
“Suppose you take a look. I may have missed something,” Bob proposed handing the flash light to Jack.
For some time they did not speak while Jack moved about throwing the light over every part of the walls and roof. He had already examined the floor in hopes that there might be another trap door.
“Come over here a minute, Bob,” he finally called.
Then, as his brother joined him in the right corner farthest from the hole through which they had crawled, he pointed upward with the flash.
“What do you think of it?” he asked after a moment had passed.
“I think I see what you mean,” Bob replied. “That rocky ledge like stone which juts out there doesn’t seem to meet the roof, is that it?”