“But—is there no danger of losing our way?”
“I think not.”
“And if we come out on top of the mountain, shall we return this way?”
“We shall see.”
As they advanced now, the situation became one filled with terrors.
It was as if they were in a literal pandemonium. All sorts of strange sounds were about them.
There was a rumble of thunder, the gurgle of molten liquid and the hiss of steam. Then terrific explosions came with fearful echoes through the cavernous depths.
It was sufficient to strike fear into a strong man’s bosom. For a time even Frank Reade, Jr., himself was a trifle daunted.
“Is it quite safe, Frank?” asked Randall, with some apprehension. “Suppose a stream of lava should come tearing down this passage?”
“It would cook us,” said Frank, imperturbably, “but we won’t anticipate that.”