He reached over behind his seat and brought out a stubby pole like a fishpole with a very large reel. There was also a headset, and something very much like a large aluminum fish on the end of the line.
"You know Geiger counters?" called the pilot. "Stick on these headphones and listen!"
Joe slipped on the headset. The pilot threw a switch and Joe heard clickings. They had no pattern and no fixed frequency. They were clickings at strictly random intervals, but there was an average frequency, at that.
"Let the counter out the window," called the pilot, "and listen. Tell me if the noise goes up."
Joe obeyed. The aluminum fish dangled. The line slanted astern from the wind. It made a curve between the pole and the aluminum plummet, which was hollow in the direction of the plane's motion. The pilot squinted down and began to swing in a wide circle around the spot where an apparently dead man had been sighted, and above which puffs of smoke now floated.
Three–quarters of the way around, the random clickings suddenly became a roar.
Joe said: "Hey!"
The pilot swung the plane about and flew back. He pointed to the button he'd pushed.
"Poke that when you hear it again."
The clickings…. They roared. Joe pushed the button. He felt the tiny impact.
"Once more," said the pilot.
He swung in nearer where the dead man lay. Joe had a sickening idea of who the dead man might be. A sudden rush of noise in the headphones and he pushed the button again.
"Reel in now!" shouted the pilot. "Our job's done."
Joe reeled in as the plane winged steadily back toward the Shed. There were puffs of smoke floating in the air behind. They had been ranged on at the instant they appeared. Somebody back at the Shed knew that something that needed to be investigated was at a certain spot, and the two later puffs of smoke had said that radioactivity was notable in the air along the line the two puffs made. Not much more information would be needed. The meaning of Braun's warning that his tip was "hot" was definite. It was "hot" in the sense that it dealt with radioactivity!
The plane dipped down and landed by the great doors again. It taxied up and the pilot killed the motor.
"We've been using Geigers for months," he said pleasedly, "and never got a sign before. This is one time we were set for something."
"What?" asked Joe. But he knew.
"Atomic dust is one good guess," the pilot told him. "It was talked of as a possible weapon away back in the Smyth Report. Nobody's ever tried it. We thought it might be tried against the Platform. If somebody managed to spread some really hot radioactive dust around the Shed, all three shifts might get fatally burned before it was noticed. They'd think so, anyhow! But the guy who was supposed to dump it opened up the can for a look. And it killed him."
He climbed out of the plane and went to the doorway. He took a telephone from a guard and talked crisply into it. He hung up.
"Somebody coming for you," he said amiably. "Wait here. Be seeing you."
He went out, the motor kicked over and caught, and the tiny plane raced away. Seconds later it was aloft and winging southward.
Joe waited. Presently a door opened and something came clanking out. It was a tractor with surprisingly heavy armor. There were men in it, also wearing armor of a peculiar sort, which they were still adjusting. The tractor towed a half–track platform on which there were a crane and a very considerable lead–coated bin with a top. It went briskly off into the distance toward the north.
Joe was amazed, but comprehending. The vehicle and the men were armored against radioactivity. They would approach the dead man from upwind, and they would scoop up his body and put it in the lead–lined bin, and with it all deadly radioactive material near him. This was the equipment that must have been used to handle the dud atom bomb some months back. It had been ready for that. It was ready for this emergency. Somebody had tried to think of every imaginable situation that could arise in connection with the Platform.
But in a moment a guard came for Joe and took him to where the Chief and Haney and Mike waited by the still incompletely–pulled–away crates. They had some new ideas about the job on hand that were better than the original ones in some details. All four of them set to work to make a careful survey of damage—of parts that would have to be replaced and of those that needed to be repaired. The discoveries they made would have appalled Joe earlier. Now he merely made notes of parts necessary to be replaced by new ones that could be had within the repair time for rebalancing the rotors.
"This is sure a mess," said Haney mournfully, as they worked. "It's two days just getting things cleaned up!"
The Chief eyed the rotors. There were two of them, great four–foot disks with extraordinary short and stubby shafts that were brought to beautifully polished conical ends to fit in the bearings. The bearings were hollowed to fit the shaft ends, but they were intricately scored to form oil channels. In operation, a very special silicone oil would be pumped into the bearings under high pressure. Distributed by the channels, the oil would form a film that by its pressure would hold the cone end of the bearing away from actual contact with the metal. The rotors, in fact, would be floated in oil just as the high–speed centrifuge the Chief had mentioned had floated on compressed air. But they had to be perfectly balanced, because any imbalance would make the shaft pierce the oil film and touch the metal of the bearing—and when a shaft is turning at 40,000 r.p.m. it is not good for it to touch anything. Shaft and bearing would burn white–hot in fractions of a second and there would be several devils to pay.
"We've got to spin it in a lathe," said the Chief profoundly, "to hold the chucks. The chucks have got to be these same bearings, because nothing else will stand the speed. And we got to cut out the bed plate of any lathe we find. Hm. We got to do our spinning with the shaft lined up with the earth's axis, too."
Mike nodded wisely, and Joe knew he'd pointed that out. It was true enough. A high–speed gyro could only be run for minutes in one single direction if its mount were fixed. If a precisely mounted gyro had its shaft pointed at the sun, for example, while it ran, its axis would try to follow the sun. It would try not to turn with the earth, and it would wreck itself. They had to use the cone bearings, but in order to protect the fine channellings for oil they'd have to use cone–shaped shims at the beginning while running at low speed. The cone ends of the shaft would need new machining to line them up. The bearings had to be fixed, yet flexible. The―
They had used many paper napkins the night before, merely envisioning these details. New problems turned up as the apparatus itself was being uncovered and cleaned.
They worked for hours, clearing away soot and charred material. Joe's list of small parts to be replaced from the home plant was as long as his arm. The motors, of course, had to be scrapped and new ones substituted. Considering their speed—the field strength at operating rate was almost imperceptible—they had to be built new, which would mean round–the–clock work at Kenmore.
A messenger came for Joe. The security office wanted him. Major Holt's gloomy secretary did not even glance up as he entered. Major Holt himself looked tired.
"There was a man out there," he said curtly. "I think it is your friend Braun. I'll get you to look and identify."
Joe had suspected as much. He waited.
"He'd opened a container of cobalt powder. It was in a beryllium case. There was half a pound of it. It killed him."
"Radioactive cobalt," said Joe.
"Definitely," said the Major grimly. "Half a pound of it gives off the radiation of an eighth of a ton of pure radium. One can guess that he had been instructed to get up as high as he could in the Shed and dump the powder into the air. It would diffuse—scatter as it sifted down. It would have contaminated the whole Shed past all use for years—let alone killing everybody in it."