and the wings outside
began to flap, and the car mounted into the air like a startled bird and
flew out quickly over the pit.

Branasko bit his lip, and Johnston heard him stifle an exclamation of
impatience. As for the American, he was at once thrilled and fascinated
by the awful sight below; he could now see beneath the overhanging mouth
of the pit, and look far down into a boundless lake of molten matter
that seemed as restless as an ocean in a storm.

Then the air became so hot he could hardly breathe. He looked at the
Alphian in alarm. The latter was whirling the wheel first one way and
then another with a startled look of fear in his eyes, and then Johnston
noticed that the walls of the pit were rising about them, and the black
canopy overhead rapidly receding.

They were sinking down into the fire.

Almost wild with terror, the American sprang toward the wheel, but
Branasko pushed him away roughly.

"Stand back," he ordered gruffly. "It is the heat; let me alone!"

The American sank into his seat. The heat became more and more intense.
Both men were purple in the face, and the perspiration was rolling from
their bodies in streams. Down sank the machine.

"I can't manage it," said Branasko hoarsely, "we'd as well give up."
Just then Johnston noticed the mouth of a cave behind Branasko.

"Look," he cried, "can't we get into it?"

Branasko looked over his shoulder, and, as he saw the cave, he uttered a
glad cry. He quickly turned the wheel and drew out a lever at his right.
The machine obeyed instantly; it swerved round suddenly and dived
into the cave. The cool air soon revived them, and Branasko had little
trouble in bringing the car to a resting-place on the rocky floor of the
cave. Before them hung impenetrable darkness, behind a curtain of red
light.

"We are in a pretty pickle now," said Johnston despondently, as they
alighted from the car.

"Nothing to do but to make the best of it," sighed Branasko.

"Perhaps this cave may lead out into some place of safety."

Johnston's eyes had become somewhat accustomed to the gloom, and he
began to peer into the darkness.

"I see a light," he exclaimed; "it cannot be a reflection from the fire
in the pit, for it is whiter."

The Alphian gazed at it steadily for a moment, then he said decidedly:
"We must go and see what it is." Without another word he started toward
the white, star-like spot, sliding his hand over the rocky wall, and
springing over a fi