“Neither am I,” declared Jerry. “It was a lucky escape for both of us. I haven’t got a bruise.”

“No wonder,” replied Hamp, in an injured tone. “You landed right on top of me. I’m just getting my wind back.”

“I’m awfully sorry,” said Jerry, “but I couldn’t help it.”

“Oh, that’s all right. Only if I had known you were coming, I would have crawled out of the way. Where are we, anyhow?”

“That’s what I want to know,” Jerry replied. “It must be a cavern, Hamp. The entrance was on top, and it got snowed over in the big storm.”

“Some one broke through the crust before us,” said Hamp, “for I saw the marks as I was falling.”

“Then he’s in here now, whoever he is,” whispered Jerry, in a startled voice. “He couldn’t have reached the hole to get out.”

There was a moment of terrible silence. The boys huddled close together and shivered with fear. Their hearts beat loudly and rapidly.

“I don’t hear anything,” whispered Hamp. “Do you?”

“Not a sound,” replied Jerry. “Wait a second. I’ll settle the matter.”