"Right!" It was a chorus.

Cargraves nodded. "I felt the same way. I took my first degree in mechanical engineering with the notion that rockets were mechanical engineering and that I would need the training. I worked as an engineer after graduation until I had saved up enough to go back to school. I took my doctor's degree in atomic physics, because I had a hunch- oh, I wasn't the only one! -I had a hunch that atomic power was needed for practical space ships. Then came the war and the Manhattan Project. When the Atomic Age opened up a lot of people predicted that space flight was just around the corner. But it didn't work out that way-nobody knew how to harness the atom to a rocket. Do you know why?"

Somewhat hesitantly Ross spoke up. "Yes, I think I do."

"Go ahead."

"Well, for a rocket you need mass times velocity, quite a bit of mass in what the jet throws out and plenty of velocity. But in an atomic reaction there isn't very much mass and the energy comes out in radiations in all directions instead of 2 nice, lined-up jet. Just the same-"

"‘Just the same' what?"

"Well, there ought to be a way to harness all that power. Darn it—with so much power from so little weight, there ought to be some way."

"Just what I've always thought," Cargraves said with a grin. "We've built atomic plants that turn out more power than Boulder Dam. We've made atomic bombs that make the two used in the war seem like firecrackers. Power to burn, power to throw away. Yet we haven't been able to hook it to a rocket. Of course there are other problems. An atomic power plant takes a lot of shielding to protect the operators—you know that. And that means weight. Weight is everything in a rocket. If you add another hundred pounds in dead load, you have to pay for it in fuel. Suppose your shield weighed only a ton—how much fuel would that cost you, Ross?"

Ross scratched his head. "I don't know what kind of fuel you mean nor what kind of a rocket you are talking about—what you want it to do."

"Fair enough," the scientist admitted. "I asked you an impossible question. Suppose we make it a chemical fuel and a moon rocket and assume a mass-ratio of twenfy to one. Then for a shield weighing a ton we have to carry twenty tons of fuel."

Art sat up suddenly. "Wait a minute, Uncle Don."

"Yes?"

"If you use a chemical fuel, like alcohol and liquid oxygen say, then you won't need a radiation shield."

"You got me, kid. But that was just for illustration. If you had a decent way to use atomic power, you might be able to hold your mass-ratio down to, let's say, one-to-one. Then a one-ton shield would only require one ton of fuel to carry it. That suit you better?"

Art wriggled in excitement. "I'll say it does. That means a real space ship. We could go anywhere in it!"

"But we're still on earth," his uncle pointed out dryly. "I said ‘if.' Don't burn out your jets before you take off. And there is still a third hurdle: atomic power plants are fussy to control—hard to turn on, hard to turn off. But we can let that one alone till we come to it. I still think we'll get to the moon."

He paused. They waited expectantly.

"I think I've got a way to apply atomic power to rockets." Nobody stood up. Nobody cheered. No one made a speech starting, "On this historic occasion-" Instead they held their breaths, waiting for him to go on.

"Oh, I'm not going into details now. You'll find out all about it, if we work together."

"We will!"

"Sure thing!"

"I hope so. I tried to interest the company I was with in the scheme, but they wouldn't hold still."

"Gee whillickers! Why not?"

"Corporations are in business to make money; they owe that to their stockholders. Do you see any obvious way to make money out of a flight to the moon?"

"Shucks." Art tossed it off. "They ought to be willing to risk going broke to back a thing like this."

"Nope. You're off the beam, kid. Remember they are handling other people's money. Have you any idea how much it would cost to do the research and engineering development, using the ordinary commercial methods, for anything as big as a trip to the moon?"

"No," Art admitted. "A good many thousands, I suppose."

Morrie spoke up. "More like a hundred thousand."

"That's closer. The technical director of our company made up a tentative budget of a million and a quarter."

"Whew!"

"Oh, he was just showing that it was not commercially practical. He wanted to adapt my idea to power plants for ships and trains. So I handed in my resignation."

"Good for you!"

Morrie looked thoughtful. "I guess I see," he said slowly, "why you swore us to secrecy. They own your idea."

Cargraves shook his head emphatically, "No, not at all. You certainly would be entitled to squawk if I tried to get you into a scheme to jump somebody else's patent rights—even if they held them by a yellow-dog, brain-picking contract." Cargraves spoke with vehemence. "My contract wasn't that sort. The company owns the idea for the purposes for which the research was carried out—power. And I own anything else I see in it. We parted on good terms. I don't blame them. When the Queen staked Columbus, nobody dreamed that he would come back with the Empire State Building in his pocket."

"Hey," said Ross, "these senior prizes—they aren't big enough. That's why nobody has made a real bid for the top ones. The prize wouldn't pay the expenses, not for the kind of budget you mentioned. It's a sort of a swindle, isn't it?"

"Not a swindle, but that's about the size of it," Cargraves conceded. "With the top prize only $250,000 it won't tempt General Electric, or du Pont, or North American Atomic, or any other big research corporation. They can't afford it, unless some other profit can be seen. As a matter of fact, a lot of the prize money comes from those corporations." He sat up again. "But we can compete for it!"

"How?"

"I don't give a darn about the prize money. I just want to go!" "Me too!" Ross made the statement; Art chimed in.

"My sentiments exactly. As to how, that's where you come in. I can't spend a million dollars, but I think there is a way to tackle this on a shoestring. We need a ship. We need the fuel. We need a lot of engineering and mechanical work. We need overhead expenses and supplies for the trip. I've got a ship."

"You have? Now? A space ship?" Art was wide-eyed.

"I've got an option to buy an Atlantic freighter-rocket at scrap prices. I can swing that. It's a good rocket, but they are replacing the manned freighters with the more economical robot-controlled jobs. It's a V-17 and it isn't fit to convert to passenger service, so we get it as scrap. But if I buy it, it leaves me almost broke. Under the UN trusteeship for atomics, a senior member of the Global Association of Atomic Scientists—that's me!" he stuck in, grinning, "can get fissionable material for experimental purposes, if the directors of the Association approve. I can swing that. I've picked thorium, rather than uranium-235, or plutonium-never mind why. But the project itself had me stumped, just too expensive. I was about ready to try to promote it by endorsements and lecture contracts and all the other clap- trap it sometimes takes to put over scientific work -when I met you fellows."

He got up and faced them. "I don't need much to convert that old V-17 into a space ship. But I do need skilled hands and brains and the imagination to know what is needed and why. You'd be my mechanics and junior engineers and machine-shop workers and instrument men and presently my crew. You'll do hard, dirty work for long hours and cook your own meals in the bargain. You'll get nothing but coffee-and-cakes and a chance to break your necks. The ship may never leave the ground. If it does, chances are you'll never live to tell about it. It won't be one big adventure. I'll work you till you're sick of me and probably nothing will come of it. But that's the proposition. Think it over and let me know."