This rock was separate from the rest of the mountain and was in motion, turning slowly around and around as if upon a pivot. When first they came to it there was a solid wall before them; but presently it revolved until there was exposed a wide, smooth path across it to the other side. This appeared so unexpectedly that they were unprepared to take advantage of it at first, and allowed the rocky wall to swing around again before they had decided to pass over. But they knew now that there was a means of escape and so waited patiently until the path appeared for the second time.

The children and the Wizard rushed across the moving rock and sprang into the passage beyond, landing safely though a little out of breath. Jim the cab–horse came last, and the rocky wall almost caught him; for just as he leaped to the floor of the further passage the wall swung across it and a loose stone that the buggy wheels knocked against fell into the narrow crack where the rock turned, and became wedged there.

They heard a crunching, grinding sound, a loud snap, and the turn–table came to a stop with its broadest surface shutting off the path from which they had come.

"Never mind," said Zeb, "we don't want to get back, anyhow."

"I'm not so sure of that," returned Dorothy. "The mother dragon may come down and catch us here."

"It is possible," agreed the Wizard, "if this proves to be the path she usually takes. But I have been examining this tunnel, and I do not see any signs of so large a beast having passed through it."

"Then we're all right," said the girl, "for if the dragon went the other way she can't poss'bly get to us now."

"Of course not, my dear. But there is another thing to consider. The mother dragon probably knows the road to the earth's surface, and if she went the other way then we have come the wrong way," said the Wizard, thoughtfully.

"Dear me!" cried Dorothy. "That would be unlucky, wouldn't it?"

"Very. Unless this passage also leads to the top of the earth," said Zeb. "For my part, if we manage to get out of here I'll be glad it isn't the way the dragon goes."

"So will I," returned Dorothy. "It's enough to have your pedigree flung in your face by those saucy dragonettes. No one knows what the mother might do."

They now moved on again, creeping slowly up another steep incline. The lanterns were beginning to grow dim, and the Wizard poured the remaining oil from one into the other, so that the one light would last longer. But their journey was almost over, for in a short time they reached a small cave from which there was no further outlet.