“There’s no such thing as a ghost, as you and I both know,” Buck responded, resenting anything that might tend to make him look foolish. “That groan came from a man, and whoever he is or wherever he is the fellow isn’t far away from where we are right now.”

“What’s the matter with you two, anyway,” demanded Ollie Ogden, suddenly sitting up and rubbing his eyes, and at the same time so disturbing Harper that he too, awakened.

“Wait a minute or two and you’ll know as much as we do,” Tom replied.

But they did not have to wait that long. The words had hardly died on Tom’s lips when something most resembling the sighing of wind through the bare branches of trees, but which all four knew to be a human sound, reached their ears. And just as Buck Granger had said, it seemed to come from directly out the ground, at the spot where he had been sleeping.

Tom took the pocket searchlight over to that part of the shed and began an examination. He laid his ear to the damp earth, but could hear nothing. Then playing the light over the ground, he got down upon his hands and knees for a closer examination. Standing around him and gazing over his shoulder, the other three carefully followed his every move.

He was moving around almost in a circle, when accidentally, in a quick turn, he kicked a section of the shed wall heavily with the heel of his boot. He drew up suddenly, and the other lads crowded closer to him.

“Didn’t that seem to you to have a peculiar sound?” he asked.

“It certainly did to me,” George Harper replied.

“Like tapping a rotten watermelon,” said Buck Granger, in language more descriptive than elegant.

“Sounded hollow, anyway,” put in Ollie Ogden.