The earth flung back the roaring of the little plane's motor. Bell had but little time to act before other planes would dart upward to seek him out. He dived, and the wing tip landing lights went on, sending fierce glares downward. Twin disks of light appeared upon the earth.

Sheds, houses, a long row of shacks as if for laborers. A drying field, on which were spread out plants with their leaves turning brown. A wall about it....

"The d.a.m.ned stuff," said Bell grimly.

He swept on. Jungle, only jungle. He banked steeply as lights flicked on and off below and as--once--the wing tip lights showed men running frantically two hundred feet below.

Then a stream of fire shot earthward, and Bell held up his hand and arm into the blast of the slip stream. It blew out the blaze that had licked at his flesh. He stared down. The gas can had left a trailing stream of fluid behind it as it went spinning down to earth. All that stream of inflammable stuff was aflame. The can itself struck earth and seemed to explode, and the trailing ma.s.s of fire was borne onward by the wind and lay across a row of thatch-roofed buildings. An incredible sheet of fire spread out. The stuff in the drying yard was burning.

Bell laughed shortly, and flung over another of his flaming bombs, and another, and the fourth....

He climbed for the skies, then, as rectangles of light showed below and planes were thrust out of their lighted hangars. Four huge conflagrations were begun. One was close by a monster rounded tank, and Bell watched with glistening eyes as it crept closer. Suddenly--it seemed suddenly, but it must have been minutes later--flame rushed up the sides of that tank, there was a sudden hollow booming, and fire was flung broadcast in a blazing, pouring flood.

"Their fuel tank!" said Bell, his eyes gleaming in the ruddy light from below. He shut off his landing lights and went upward, steeply.

"I've played h.e.l.l with them now!"

A thousand feet up. Two thousand. Two thousand five hundred.... And suddenly Bell felt cold all over. The instrument board! The motor was hot. Hot! Burning!

He shut it off before it could burst into flames, but he heard the squealing of tortured, unlubricated metal grinding to a stop. He leveled out. It was strangely, terribly silent in the high darkness, despite the roaring of wind about the gliding plane. The absence of the motor roar was the thing that made it horrible.

"Paula," said Bell harshly, "one of those plugs came out, I guess. The motor's ruined. Dead. The ship's going to crash. Ready with your parachute?"

It was dark, up there, save for the glare of fires upon the under surface of the wings. But he saw her hand, encarmined by that glare, upon the combing of the c.o.c.kpit. A moment later her face. She turned, light-dazzled, to smile back at him.

"All right, Charles." Her voice quavered a little, but it was very brave. "I'm ready. You're coming, too?"

"I'm coming," said Bell grimly. Below them was the city of The Master, set blazing by their doing. If their chutes were seen descending....

And if they were not.... "Count ten," said Bell hoa.r.s.ely, "and pull out the ring. I'll be right after you."

He saw the slim little black-clad figure drop, plummetlike, and prayed in an agony of fear. Then a sudden blooming thing hid it from sight.

Thick clouds of smoke lay over the lights and fires below.

Bell stepped over the side and went hurtling down toward the earth in his turn.

(_To be continued_)

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The Cavern World

_By James P. Olsen_

[Ill.u.s.tration: _He aimed it, and the Thing gripping him was hurled back upon the others._]

[Sidenote: A great oil field had gone dry--and Asher, trapped far under the earth among the revolting Petrolia, learns why.]

"Impossible! What sort of creatures would they be, that could live two miles beneath the surface of the earth? Surely, Asher, you are joking!"

R. Briggs Johns, mighty power back of Stan-America Oil Corporation, looked at Blaine Asher closely, expecting to see the chief geologist and scientist of the company laugh. But Blaine Asher did not laugh.

Serious, his rather thin face grave as he leaned his tall, muscular body above a torsion machine he was adjusting, there was nothing to indicate he had the faintest idea of a joke.

"Why d.a.m.n it, Asher!" Johns insisted wrathfully, "you don't really mean that. And"--he took a nervous turn around the laboratory--"if such a wild thing were possible, what has that to do with our trouble?

You haven't led me on to spend a million dollars drilling a thirty-six-inch hole, just so you could test a fantastic theory?"

"You know better than that." Asher wiped his hands and leaned against a table. Johns, looking into the cool gray eyes of the man before him, did know better. Blaine Asher was more than just a geologist or scientist. Well he might be termed a master geo-metallurgist. Johns nodded, wiping beads of perspiration from his brow.

"You say impossible--and want to know how those creatures cause this field, the largest oil field in the world, to start going bone dry over night. All right:

"Remember how you laughed when I told you that oil would some day be mined instead of pumped or flowed from the earth? You couldn't see how one central shaft could be sunk, then tunnels run back underneath the oil strata, tapping the sand from the bottom and letting the oil run down to be pumped out one shaft. Yet, that way, we would get _all_ the oil, instead of the possible one-eighth of the total amount as we get by present methods.

"Now, you have seen that done. And you said that was impossible."

"Yes," Johns objected, "but those test wells we mined were only a few hundred feet deep. Wells in this field are eight thousand feet deep!

Think of the heat, man! You can't do it. And as for people--"

"Your great field has suddenly gone dry, almost in a month's time,"

Asher stopped him. "What is happening here can happen elsewhere. Only, formations in this field are more suited to there being life--or something--below us. Stan-America is going broke. Many others have already gone broke. Still, that oil couldn't have gotten away.

"As for heat--yes, we know that oil is hot when it comes up from the oil sand at eight thousand feet, or from ordinary wells at three to six thousand feet. But"--Asher lit a cigarette and inhaled deeply--"gas coming out of the same well is _cold_! So cold it forms frost inches thick on pipes and tanks.

"Rock pressure--the pressure of the earth--forcing up the gas, causes that. Why couldn't that same pressure cool great caverns below the granite cap below the oil sands? It could. For that matter, I know that same pressure will generate useful power. I'll show you that in a minute."

"All right!" Johns chewed his cigar almost savagely. "Say, then, that you can work down there, nearly two miles underground; granted that we can tunnel from beneath the sands and pump more oil from one central shaft than we now do from fifty wells--what has that to do with this tosh about a race of people?"

"They are not people, perhaps." Asher grinned at the "there, I've stuck you!" look on Johns' face. "Let's say, rather, creatures. Have you ever met Lee Wong, the great Chinese scientist, or his Russian geological collaborator, Krenski? No?

"Well, I have. I met them in Paris in 1935--fire years ago. They're brilliant men, and they've prepared some wonderful papers. Brilliant, I said: they are also dangerous. They claim, you know, that the fossils we now drill up come from a lost race--people who went _into_ the earth while man, like us, was coming up onto the earth from the water. Some claim those fossils have been on the surface at one time, and were silted over. But eight thousand feet is a lot of silt, Johns: ever thought of that?"

"Good G.o.d!" Johns gasped hoa.r.s.ely. "You almost make me believe you are right. But, supposing there is such a race of things--what will you do?"

"This." Asher drew back a curtain that was stretched across one end of the laboratory. "You know I was working on a cage in which to descend into that eight-thousand-foot well you've drilled--the well you're going to use to try and find why this field is suddenly gone dry. This it it."

Johns stared, shook his head wonderingly and stared again. Before him, ready to be transported to the well that was larger than any ever drilled before, stood what Blaine Asher called his Miner, for want of a better name.

A thick steel tube, it was. Twelve feet long and large enough around that a man might stand inside of it. The top was welded on in much the manner a top is welded on an ordinary hot-water heater, and had connections for hose in it. At the height of a man's eyes heavy windows were set in, and in one side was a door just large enough to admit a man's body. This door sealed tight the minute it closed.

"It looks like--like some sort of a deep sea diving outfit," Johns said as he walked around the braces that held the Miner upright. "But all those gadgets inside and on the bottom--?" He indicated the strange instruments that could be seen when the door was opened, and the queer gla.s.s tubes that projected from the very bottom.