the shaft which reaches down to the wheel’s hub. His position for a moment was absurdly ungraceful. When he straightened up, his arm slid into the wheel well. But he dragged the hose the rest of the way and passed it on up. Then that tank was full and capped. The refueling crew got down to the ground and fed the hose back to the pit which devoured it. That was all. But somehow Joe remembered the sandy-haired man and his arm going up inside the wheel well for a fraction of a second.

The pilot read one part of the flight orders again and tore them carefully across. One part he touched his pocket lighter to. It burned. He nodded yet again to the co-pilot, and they swung up and in the pilots’ doorway. Joe followed.

They settled in their places in the cabin. The pilot threw a switch and pressed a knob. One motor turned over stiffly, and caught. The second. Third. Fourth. The pilot listened, was satisfied, and pulled back on the multiple throttle. The plane trundled away. Minutes later it faced the long runway, a tinny voice from the control tower spoke out of a loud-speaker under the instruments, and the plane roared down the field. In seconds it lifted and swept around in a great half-circle.

“Okay,” said the pilot. “Wheels up.”

The co-pilot obeyed. The telltale lights that showed the wheels retracted glowed briefly. The men relaxed.

“You know,” said the co-pilot, “there was the devil of a time during the War with sabotage. Down in Brazil there was a field planes used to take off from to fly to Africa. But they’d take off, head out to sea, get a few miles offshore, and then blow up. We must’ve lost a dozen planes that way! Then it broke. There was a guy—a sergeant—in the maintenance crew who was sticking a hand grenade up in the nose wheel wells. German, he was, and very tidy about it, and nobody suspected him. Everything looked okay and tested okay. But when the ship was well away and the crew pulled up the wheels, that tightened a string and it pulled the pin out of the grenade. It went off.... The master mechanic finally caught him and nearly killed him before the MPs could stop him. We’ve got to be plenty careful, whether the ground crews like it or not.”

Joe said drily: “You were, except when they were topping off. You took that for granted.” He told about the sandy-haired man. “He hadn’t time to stick anything in the wheel well, though,” he added.

The co-pilot blinked. Then he looked annoyed. “Confound it! I didn’t watch! Did you?”

The pilot shook his head, his lips compressed.

The co-pilot said bitterly: “And I thought I was security-conscious! Thanks for telling me, fella. No harm done this time, but that was a slip!”

He scowled at the dials before him. The plane flew on.

This was the last leg of the trip, and now it should be no more than an hour and a half before they reached their destination. Joe felt a lift of elation. The Space Platform was a realization—or the beginning of it—of a dream that had been Joe’s since he was a very small boy. It was also the dream of most other small boys at the time. The Space Platform would make space travel possible. Of course it wouldn’t make journeys to the moon or planets itself, but it would sail splendidly about the Earth in an orbit some four thousand miles up, and it would gird the world in four hours fourteen minutes and twenty-two seconds. It would carry atom-headed guided missiles, and every city in the world would be defenseless against it. Nobody could even hope for world domination so long as it floated on its celestial round. Which, naturally, was why there were such desperate efforts to destroy it before its completion.

But Joe, thinking about the Platform, did not think about it as a weapon. It was the first rung on the stepladder to the stars. From it the moon would be reached, certainly. Mars next, most likely. Then Venus. In time the moons of Saturn, and the twilight zone of Mercury, and some day the moons of Jupiter. Possibly a landing could be dared on that giant planet itself, despite its gravity.

The co-pilot spoke suddenly. “How do you rate this trip by cargo plane?” he asked curiously. “Mostly even generals have to go on the ground. You rate plenty. How?”

Joe pulled his thoughts back from satisfied imagining. It hadn’t occurred to him that it was remarkable that he should be allowed to accompany the gyros from the plant to their destination. His family firm had built them, so it had seemed natural to him. He wasn’t used to the idea that everybody looked suspicious to a security officer concerned with the safety of the Platform.

“Connections? I haven’t any,” said Joe. Then he said, “I do know somebody on the job. There’s a Major Holt out there. He might have cleared me. Known my family for years.”

“Yeah,” said the co-pilot drily. “He might. As a matter of fact, he’s the senior security officer for the whole job. He’s in charge of everything, from the security guards to the radar screens and the jet-plane umbrella and the checking of the men who work in the Shed. If he says you’re all right, you probably are.”

Joe hadn’t meant to seem impressive. He explained: “I don’t know him too well. He knows my father, and his daughter Sally’s been kicking around underfoot most of my life. I taught her how to shoot, and she’s a better shot than I am. She was a nice kid when she was little. I got to like her when she fell out of a tree and broke her arm and didn’t even whimper. That shows how long ago it was!” He grinned. “She was trying to act grown-up last time I saw her.”

The co-pilot nodded. There was a brisk chirping sound somewhere. The pilot reached ahead to the course-correction knob. The plane changed course. Sunshine shifted as it poured into the cabin. The ship was running on automatic pilot well above the cloud level, and at an even-numbered number of thousands of feet altitude, as was suitable for planes traveling south or west. Now it droned on its new course, forty-five degrees from the original. Joe found himself guessing that one of the security provisions for planes approaching the Platform might be that they should not come too near on a direct line to it, lest they give information to curious persons on the ground.

Time went on. Joe slipped gradually back to his meditations about the Platform. There was always, in his mind, the picture of a man-made thing shining in blinding sunlight between Earth and moon. But he began to remember things he hadn’t paid too much attention to before.

Opposition to the bare idea of a Space Platform, for instance, from the moment it was first proposed. Every dictator protested bitterly. Even politicians out of office found it a subject for rabble-rousing harangues. The nationalistic political parties, the peddlers of hate, the entrepreneurs of discord—every crank in the world had something to say against the Platform from the first. When they did not roundly denounce it as impious, they raved that it was a scheme by which the United States would put itself in position to rule all the Earth. As a matter of fact, the United States had first proposed it as a United Nations enterprise, so that denunciations that politicians found good politics actually made very poor sense. But it did not get past the General Assembly. The proposal was so rabidly attacked on every side that it was not even passed up to the Council—where it would certainly have been vetoed anyhow.

But it was exactly that furious denunciation which put the Platform through the United States Congress, which had to find the money for its construction.

In Joe’s eyes and in the eyes of most of those who hoped for it from the beginning, the Platform’s great appeal was