The Black Star Passes by John W. Campbell (read e book .txt) 📕

Molecules move because of temperature, and lack of motion means lack of heat. These molecules that have been slowed down are then cold; they will absorb heat from the air about them, and since the molecule of hydrogen gas at room temperature is moving at about seven miles a second, when the molecules of the confined gas in our car, or the molecules of the metal bar are slowed down to but a few hundred miles an hour, their temperature drops to some hundreds of degrees below zero, and they absorb energy very rapidly, for the greater the difference in temperature, the greater the rate of heat absorption.

“I believe we will be able to accelerate the car rapidly to a speed of several miles a second at very high altitudes, and as we will be able to use a perfectly enclosed streamlined car, we should get tremendous speeds. We’ll need no wings, of course, for with a small unit pointed vertically, we’ll be able to support the car in the air. It will make possible a machine that will be able to fly in reverse and so come to a quick stop. It will steer us or it will supply us with electrical power, for we merely have to put a series of small metal bars about the circumference of the generator, and get a tremendously powerful engine.

“For our present need, it means a tremendously powerful engine⁠—and one that we can make invisible.

“I believe you can guess the source of that breeze we had there? It would make a wonderful air-conditioning unit.”

“Dick Arcot,” began Morey, his voice tight with suppressed excitement, “I would like to be able to use this invention. I know enough of the economics of the thing, if not its science, to know that the apparatus before us is absolutely invaluable. I couldn’t afford to buy the rights on it, but I want to use it if you’ll let me. It means a new era in transcontinental air travel!”

He turned sharply to Fuller. “Fuller, I want you to help Arcot with the ship to chase the Pirate. You’ll get the contract to design the new airliners. Hang the cost. It’ll run into billions⁠—but there will be no more fuel bills, no oil bills, and the cost of operation will be negligible. Nothing but the Arcot short wave tubes to buy⁠—and each one good for twenty-five thousand hours service!”

“You’ll get the rights on this if you want them, of course,” said Arcot quietly. “You’re maintaining these laboratories for me, and your son helped me work it out. But if Fuller can move over here tomorrow, it will help things a lot. Also I’d like to have some of your best mechanics to make the necessary machines, and to start the power units.”

“It’s done,” Morey snapped.

III

Early the next morning Fuller moved his equipment over to the laboratory and set up his table for work. There Arcot and Morey joined him, and the designing of the new machine was started.

“First, let’s get some idea of the most advisable shape,” Fuller began methodically. “We’ll want it streamlined, of course; roughly speaking, a cylinder modified to fit the special uses to which it will be put. But you probably have a general plan in mind, Arcot. Suppose you sketch it for us.”

The big physicist frowned thoughtfully. “Well, we don’t know much about this yet, so we’ll have to work it out. You’ll have plenty of fun figuring out strains in this machine, so let’s be safe and use a factor of safety of five. Let’s see what we’ll need.

“In the first place, our machine must be proof against the Pirate’s gas, for we won’t be riding a beam with instruments to guide us safely, if we pass out. I’ve thought that over, and I think that the best system is just what we used in the sample bottles⁠—a vacuum. His gas is stopped by nothing, so to speak, but there is no substance that will stop it! It will no doubt penetrate the outer shell, but on reaching the vacuum, it will tend to stay there, between the inner and outer walls. Here it will collect, since it will be fighting air pressure in going either in or out. The pressure inside will force it back, and the pressure outside will force it in. If we did not pump it out, it would soon build up pressure enough to penetrate the interior wall. Now, since the stuff can leak through any material, what kind of a pump shall we use? It won’t be pushed by a piston, for it will leak through either the cylinder walls or the piston. A centrifugal pump would be equally ineffective. A mercury vapor pump will take it out, of course, and keep a high vacuum, but we’d never make any progress.

“Our new machine gives us the answer. With it we can just have a number of openings in the wall of the outer shell, and set in them one of these molecular motion directors, and direct the molecules into the outside air. They can’t come in through it, and they will go out!”

“But,” Morey objected, “the vacuum that keeps out the gas will also keep out heat, as well! Since our generator is to run on heat energy, it will be rather chilly inside if we don’t remedy that. Of course, our power units could be placed outside, where the blast of air will warm them, but we really won’t have a very good streamline effect if we hang a big electric generator outside.”

“I’ve thought of that too,” Arcot answered. “The solution is obvious⁠—if we can’t bring the generator to the air, we must bring the air to it.” He began sketching rapidly on the pad before him, “We’ll have all the power equipment in this room here in the back, and the control room up in front, here. The relays for controlling will be back here, so we can control electrically