That was true, and, as the machine made a sudden plunge toward the cliff a few yards to the left of the refugees, the dead body, which the driver had managed to move to the door with his feet, fell out and lodged upon the edge of the cliff instead of falling into the fiery depths. The machine bounded up a few yards and paused, now apparently under the control of its driver. The man looked down hesitatingly at the corpse for a moment and then lowered the machine to the sloping rock near where the body lay. He alighted and cautiously crept down the steep incline to the body. He raised it in his arms and was about to cast it from him when his foot slipped, and with a cry of horror he fell with his burden over the cliff's edge into the red abyss.

Johnston uttered an exclamation of horror, but Branasko was unmoved.

After a moment he rose, and carefully scanning the s.p.a.ce overhead, he crawled on hands and knees toward the machine. Johnston heard him chuckling to himself and uttering spasmodic laughs, and he watched him closely as he reached the machine. For several minutes he seemed to be inspecting it critically, both inside and out; then he stood away from it, a bold, black silhouette on a background of flame, and motioned the American to come to him.

Johnston promptly, but not without many misgivings, obeyed his signal.

"What are you up to?" asked he, as the Alphian a.s.sisted him to rise from his hands and knees.

Branasko touched the machine and smiled. His face was shining with enthusiasm.

"The question of our returning to Alpha is settled," he said sententiously.

"How?"

"We can go in this."

"Can you manage it?"

"Easily; that fellow must have been drunk; the machine is in good order, I think."

"When do you propose to start?" and the American eyed the funeral-car dubiously.

"The night is before us; we could not get a better time." As he spoke he entered the car and laid his hand on the wheel. Johnston, obeying his nod, followed, shuddering as he remarked the traces of blood on the floor.

"All right!" Branasko turned the wheel slowly, 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.

Branas...o...b..t 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 hoa.r.s.ely, "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 fissure in the floor.

Gradually the light grew brighter, till, as they suddenly rounded a cliff, a grand sight burst upon their view. They found themselves in a vast dome-shaped cavern, thousands of yards in diameter and height.

And almost in the centre of the floor, from a red and purple mound of cooling lava, leapt a white stream of molten matter from the floor to the dome. And in the black dome, where the lava turned to molten spray, hung countless stalact.i.tes of every color known to the artistic eye. And from the foot of the fountain ran a tortuous rivulet that lighted the walls and roof of a narrow chamber that extended for miles down toward the bowels of the earth.

Branasko was delighted.

"The king does not know of this," he declared, "else he would make it accessible to his people, and call it one of the wonders of Alpha.

By accidentally sinking into the pit we have discovered it. But," he concluded, "we must at once try to find some way out other than that by which we came."

They turned from the beautiful fountain, and, holding to each other's hands, and aided by the light behind them, they stumbled laboriously through the semi-darkness. Branasko's ears were very acute. He paused to listen.

"Hark ye!" he cautioned.

The combined roar of the pit and the fountain of lava had sunk to a low murmur, but ahead of them they now heard a rushing sound like a distant tornado.

"Come on," said the Alphian, and he drew his companion after him with an eagerness the American was slow to understand. The light in the cavern gradually grew brighter. By a circuitous route they were again approaching the pit of fire, though it was still hidden from sight.

Finally they reached a point where the wind was blowing stiffly, and further on a volume of cold spray suddenly dashed upon them and wet them to the skin. And when their eyes had become accustomed to the rolling mist, they saw a great lake, and pouring into it from high above was a mighty waterfall.

"Mercy!" e.j.a.c.u.l.a.t.ed the Alphian, in great alarm. "If this is salt water we are lost. All Alpha will come to an end!"

"What do you mean?" And Johnston wondered if Branasko's trials and struggle could have turned his brain.

"If it be salt water, then it has broken in from the ocean above Alpha,"

he explained. "The king has often said that not a drop of the ocean has ever entered the great cavern."

Branasko stooped and wet his hand in a little pool at his feet. "I am almost afraid to taste it," said he, holding his hand near his mouth.

"It would settle all our fates." He waited a moment and then touched his fingers to his tongue.

"Salt!" That was all he said for several moments. He folded his arms and looked mutely toward the boiling lake. Presently he raised his eyes to the great hole in the roof, and groaned: "The break is gradually widening. These stones are freshly broken, and the great bowl is filling."

"It will fill all Alpha with water and drown every soul in it," added the terrified American.

"That, however, is not the most immediate danger," said Branasko wisely.

"They would first suffocate, and later their bodies would be swallowed up in the stomach of the earth."

"What do you mean?"

Branasko shrugged his shoulders. "As soon as this bowl is filled with water, which would not take many hours, it would run over into the lake of fire and produce an explosion that would rend Alpha from end to end."

"Who knows, it might turn the whole Atlantic into the centre of the earth, and destroy the entire earth." But Branasko was unable to grasp the full magnitude of the remark, for to him the world was simply a vast cavern lighted by human ingenuity. He fastened a narrow splinter of stone upright in the shallow water at his feet, and, lying down on his stomach with his eyes close to it, he studied it for several minutes.