Murray Leinster

“ Poured into the air at sufficiently high level—doubtless carried up by a column of hot air—finely-divided dust and deadly gas could travel for hundreds of miles before touching earth. Apparently they did. Where they touched earth, nothing could live.
Not only did living things die after breathing in the deadly stuff but the ground itself became murderous. To walk on an area where the ground emitted radioactive radiation was to die. To breathe the air exposed to those rays....
Murfree went desperately on in his search for the impossible source of the invisible carriers of death. ”

“ Ten miles away—the car ran perfectly from the first, in proof that there was no longer a neutron-flood to ionize the air—ten miles away they saw rain falling upon smokily flaming hillsides. Lightning flashed among dark clouds. Water poured down. Not even a forest fire could survive such a downpour.
They went back to Brandon. It took them a day and night of steady driving, alternating at the wheel. Bud Gregory had little to say the whole way back. But when Murfree stopped the car before the repair shed and let him out Gregory grinned uncomfortably. ”

“ Something like a uranium pile has started up somewhere in these hills. It's on a scale that nobody's ever imagined before. It's so big that it's incredible that human beings could have started it. It's pouring out radioactive dust and gases into the air. They're being spread by the winds. Where the stuff lands everything dies.
"And the pile is increasing in size and violence. If it keeps on increasing, it will make at least this continent uninhabitable, and it may destroy all the life in the world. Not only all human life but every bird and beast and even the fish in the ocean deeps. ”

“ When as many are freed as escape the pile, a chain reaction sustains itself. But when none can escape, there is no minimum size. There is no minimum purity of materials. Prevent neutrons from escaping and anything at all, of any size, becomes an atomic pile.
Murfree passed over a third dollar bill.
"Now I'm paying you to listen to me," he said evenly. "That man used your outfit and made a circular block for neutrons a quarter-mile across with the horn pointed down. Maybe a million, maybe five million tons of rock were inside it. Maybe there was some uranium in it too. ”

“ He looked enormously concerned.
"Nobody can live to get to it to turn it off," said Murfree, grimly. "Maybe a plane can drop a bomb that will blast it. But it'll be weeks before I can make myself believed. Meanwhile there's poison being poured into the air. People are dying right now.
"For five miles around that thing you made, there's not even a blade of grass alive. The people in the cabins for ten miles around are dying and don't know why. And that horn-shaped mass of ore and earth inside your field is full of more flying neutrons than any atom pile ever was. ”

“ Whatever had begun a chain reaction outside of Oak Ridge and Handford and however it had become possible, it staggered the imagination. The output of murderous by-products increased day by day. It was building up to an unimaginable climax.
There was no danger of an atomic explosion, of course. An atomic pile does not blow up. But by the amount of by-products released, something on the order of a small but increasing volcano was at work somewhere. Instead of giving off relatively harmless gases and smoke, it gave off the most deadly substances known to men. ”

“ Murfree saw. He saw much more than Bud Gregory could tell him. He envisioned a quarter-mile circle of wire, built in a remote mountain valley. It made a horn-shaped—cone-shaped—barrier reaching down into the earth. Nothing could pass through that barrier, not even neutrons.
There is some slight radioactivity everywhere. Even rocks possess it. It is the cause of the internal heat of the earth. Perhaps the unknown man had come upon indications of uranium ore underground in that valley, perhaps not. ”

“ Bud Gregory grinned lazily.
"Too much trouble. Took me a day an' a half to put it together an' get it workin'. I don't like that kinda work."
"A hundred dollars? Five hundred? And royalties?"
Bud Gregory shrugged.
"Too much trouble," he said. "I get along. Don't aim to work myself to death. You can go along now. Your car's all right."
He shambled over to his chair. He seated himself with an air of infinite relaxation and leaned back against the corner of the shed. As Murfree drove away he raised one hand in utterly lazy farewell.
But Murfree drove down the red-clay road, marveling. ”

“ The family in the house was dying. He gave them water and stayed to prepare food for them. There was absolutely nothing else to be done. He knew what had happened, of course. They had been burned—painlessly, like sunburn—by the radiations from that monstrous atomic furnace which somewhere steadily poisoned the air. The burns went deep into their bodies. ”

“ But an ordinary man, looking at a Geiger counter, does not understand that a tiny particle at high velocity—so small that it passes through a glass tube and a metal lining without hindrance—makes a Geiger tube temporarily conductive. Murfree stared blankly at Bud Gregory. ”

“ But, surrounded by a shield through which no neutron could escape, any mass of material on earth would become an atomic pile!
A single molecule of uranium in any mass of rock will sooner or later disintegrate, giving off high-speed neutrons. Normally they travel indefinitely and are harmless. Some go up into the air and may ionize a single molecule. Some may find a fissionable atom and disrupt it. ”

“ He was untutored and almost illiterate, while Murfree had spent years in the study of just such science as this should represent. So Murfree helped as a naked savage might help to set up a radio-beam, in absolute ignorance of even its basic principles.
"Like I told you," said Bud Gregory in a troubled voice, "this new outfit is like that there thing that makes that—uh—pile. Only this don't make a hollow horn. This here is solid. It won't only stop them—uh—neutrons from goin' through a place. It'll stop 'em dead in their tracks, right where they are when it hits. It's gonna make a lot of heat." ”

“ Within a barrier from which they cannot escape, they would bounce backward and forward until, within even a limited mass of matter, they did disrupt another atom. Neutrons from that disrupted atom would then go on and on!
An ordinary atomic pile must be of a certain minimum size because it loses so many neutrons from its outer surface that no chain reaction can maintain itself. As the size of the pile increases the number that does not escape increases faster than the number that does. There is a size where enough strike fissionable atoms before escaping to maintain the reaction. ”

“ And something's got to be done!"
"But—"
"I brought you so far with me," said Murfree doggedly, "because you were no safer in Washington than anywhere else. So far, death from the thing is a matter of pure chance. Wherever it's happening the ground must be so hot that a column of air rises from it like smoke from a forest fire. ”

“ He went off, but a week later he come back ragin' that he couldn't sell his car. Nobody'd buy it without a regular radiator workin'. How long I been talkin'?"
Murfree silently passed over another dollar bill. Bud Gregory was decidedly something that there is no word for. He knew intuitively the things that trained scientists have as yet only partly found out. Just as some men know by instinct where fish will be found and what bait they will rise to, Bud Gregory knew the behavior of atoms and electrons. ”

“ Murfree said bitterly. "I kept going in hope of coming on a repair shop. Can you fix it? Will the motor freeze up?"
Bud spoke negligently, looking at the car and all the parcels.
"Uh-huh. Oil's all burnt up in the cylinders. When she cools she freezes. But if you pour water in 'er now you'll bust the cylinder-block."
Murfree clamped his jaws. His hands clenched.
He wasn't far enough into the Smokies for his needs and that power-line-loss business meant that he had to hurry.
"Any chance of getting another car?" he asked desperately. ”

“ But it was no more impossible than welding a water-pump shaft in its place or eliminating all friction from a frozen-tight motor so that it could be started again, or, say looking at a Geiger Counter and understanding how it worked without the least idea of what it could be used for.
Murfree had a small camera and dutifully took pictures without attempting to go closer. He had no hope that the pictures would turn out. The plates were surely fogged by the radiation. He bent his cadmium plate into a half-cylinder and did his best to make sure of what he now unreasonably knew. ”

“ He had simply reversed the normal process of turning current into heat, and had turned heat into electricity to cool a motor. The direct transformation of heat into electricity has been a scientists' dream for a hundred years, one never accomplished.
But Bud Gregory had done it to save himself the trouble of repairing a shattered radiator.
"So," said Bud Gregory, "I stuck that wire in a hose an' bypassed the radiator. It'd take out the heat an' give current. I strung some ordinary wire under the car to use up the current. That's all.
"The car run good. ”

“ North America would probably become uninhabitable in months or at most a year or two. There might be some areas on the West Coast where prevailing winds could keep away the poison for a time, but it was entirely possible that ultimately the whole earth would become a desert of radioactive sand and its seas empty of even microscopic life. ”

“ Murfree fidgeted when he heard it. He made his family sleep with closed windows that night in spite of the stuffiness of their rooms, and they started off again near daybreak.
It was about three in the afternoon when he met Bud Gregory.
Bud Gregory sat in splendid somnolence before the shed which was his repair shop. The village of Brandon was a metropolis of three hundred souls, not far within the Great Smokies. There were mountains in every direction. There was blue sky overhead. There was red clay underfoot. ”

“ Then Murfree piled his wife and small daughter in the car, drew out all the rest of the money he had in the bank and headed for the Great Smokies.
It was strictly logical action. Epidemic leukemia in Cincinnati, ruined Geiger counters in Washington, dead cattle in West Virginia, dead trout in Georgia, the sudden cure of cancer patients in Frankfort, Kentucky—and a ten-mile patch of dead vegetation in Pennsylvania. ”

“ It's weldin' your shaft." He looked absently into the distance. "It saves a lotta work," he added without interest.
"But—but you can't weld a shaft without taking it out!" protested Murfree. "It'd short!"
Bud Gregory yawned.
"This don't. It's some kinda stuff them tubes make. It don't go through iron. It just kinda bounces around. Where there's a break, it heats up an' welds. When it's all welded it just bounces around."
Murfree swallowed. He walked around the car and looked at the apparatus in the cheesebox. ”

“ I'll fix 'er so she can run for ten dollars.' I thought that'd scare him off, but he took me up. An' I didn't know how to fix it, but I knew I could figger out a way.
"So I got to thinkin', with him pacin' up an' down waitin' for me to set to work. An' I thought to myself, 'Fixin' that radiator is a job of work! It'd be easier to figger out some other way to keep her cool!' An' then it come to me."
"What?"
"All a radiator does," drawled Bud Gregory, "is let the heat get out of the coolin' water. His radiator wasn't no good. ”

“ Bud Gregory shrugged.
"Steel is little hunks of stuff stickin' together. These tubes make a kinda stuff that makes the outside ones slide easy on each other. I fixed up this dinkus to help loosen nuts that was too tight an' for workin' on axles an' so on. That'll be five dollars. Okay?"
"Y-yes—my word!" said Murfree. ”