progress, but this was impossible, and they continued to roll for several minutes. Then Dave bumped into some sort of barrier and Roger landed beside him.
"For gracious sake, what's this?" gasped Roger, when he felt able to speak. The breath had been all but knocked out of him.
"I guess we have found one of the caves," answered Dave, grimly. "Phew, but that was some roll, wasn't it! "
"We must be down near the center of the earth," murmured the senator's son.
"Not quite as bad as that. But we came down some distance, I admit."
"Flash that light around, Dave, and let us see where we are."
"I will if the light hasn't been smashed," replied our hero. "I rolled over it half a dozen times."
He brought out the little flashlight and tried it. Fortunately, it was still in working order. As the rays fell around the lads, they stared at each other, blankly.
"What do you make of this, Dave?"
"Looks as if it was cut out of the solid rock, Roger."
"It certainly is some cave. Wonder where it leads to?"
"We might follow the opening and find out."
