"Gee, I hope we can get to them," said Archer.
"What you got to do, you can do," Tom answered. "I wonder——"
"Sh-h. D'you hearr that?" Archer whispered, clutching Tom's shoulder. "It was much nearerr—right close——"
They held their breaths as the reverberation of a sharp report died away.
"What was it?" Archer asked tensely.
"I don't know," Tom whispered, instinctively removing the short stick and closing the trap door tight. "Don't move—hush!"