"We don't know how our velocity matches this thing," said Kim after an instant. "We could be drifting toward the edge of the shadow. You watch the stars all around. Make sure I head directly for that blackness. When we touch, I'll see what I can find out."
He reversed the ship's direction. He let the Starshine float down backward. The mass of unsubstantial darkness seemed to swell. It engulfed more and more of the cosmos. . . .
A long, long time later, there was a strange sensation in the feel of things. Dona gave a little cry.
"Kim! I feel queer! So queer!"
Kim moved heavily. His body resisted any attempt at motion, and yet he felt a horrible tension within him, as if every molecule were attempting to fly apart from every other molecule. The controls of the ship moved sluggishly. Each part of each device seemed to have a vast inertia. But the controls did yield. The drive did come on. A little later the sensation ended. But both Kim and Dona felt utterly exhausted.
"It—was getting dark, too," said Dona. She trembled.
"When we tried to move," said Kim, "our arms had a tendency to move at right angles to the way we wanted them to, at all the possible right angles at once. That was the edge of the shield, Dona. Now we'll see what we've got."
He uncovered the recording cabinet. There had been no need to set up instruments especially for the analysis of the field. They had been a part of the Starshine's original design for exploration. Now Kim read the records.
"Cosmic-ray intensity went down," he reported, studying the tapes. "The dielectric constant of space changed. It just soared up. The relationship of mass to inertia. That particular gadget never recorded anything significant before, Dona. In theory it should have detected space-warps. Actually, it never amounted to anything but a quantitative measure of gravitation on a planet one landed on. But it went wild in that field! And here! Look!"
He exultantly held out a paper recording. "Glance at that, Dona! See? A magnetometer to record the strength of the magnetic field on a new planet. It recorded the ship's own field in the absence of any other. And the ship's field dropped to zero! Do you see? Do you?"
"I'm afraid not," admitted Dona. But she smiled at the expression on Kim's face.
"It's the answer!" said Kim zestfully. "Still I don't know .v that blasted field is made, but I know now how it works. Neutrons have no magnetic field, but this thing turns them aside. Alpha and beta and gamma radiation do have magnetic fields, but this thing turns them aside, too. And the point is that it neutralizes their magnetic fields, because otherwise it couldn't start to turn them aside. So if we make a magnetic field too strong for the field to counter, it won't be able to turn aside anything in that magnetic area. The maximum force-field strength needed for the planet is simply equal to the top magnetic field the sun may project so far. If we can bury the Starshine in magnetic flux that the force-field can't handle—"
HE GRINNED. He hugged her.
"And there's a loop around the Star-shine's hull for space-radio use," he cried. "I'll run a really big current through that loop and we'll try again. We should be able to put quite a lot of juice through a six-turn loop and get a flux-density that will curl your hair!"
He set to work, beaming. It took him less than half an hour to set up a series-wound generator in the airlock, couple in a thermocell to the loop, so it would cool the generator as the current flowed and thereby reduce its internal resistance.
"Now!" he said. "We'll try once more. The more juice that goes through the outfit, the colder the generator will get and the less its resistance will be, and the more current it will make and the stronger the magnetic field will be."
He flipped a switch. There was a tiny humming noise. A meter-needle swayed over, and stayed.
The Starshine ventured into the black globe below.
Nothing happened. Nothing happened at all.
"The stars are blotted out, Kim," Dona at last said uneasily.
"But you feel all right, don't you?" He grinned like an ape in his delight.
"Why, yes."
"I feel unusually good," said Kim happily.
The vision-screens were utterly blank. The ports opened upon absolute blackness—blackness so dead and absorbent that it seemed more than merely lack of light. It seemed like something horrible pressing against the ports and trying to thrust itself in.-
And, suddenly, a screen glowed faintly, and then another... .
Then there was a greenish glow in the ports, and Dona looked out and down. Above was that blackness, complete and absolute. But below, seen with utter clarity, because of the absence of atmosphere, lay a world. Nothing grew upon it. Nothing moved. It was raw, naked rock with an unholy luminescence. Here and there the glow was brighter where mineral deposits contained more highly active material. The surface was tortured and twisted, in swirled strained writhings of formerly melted rock.
They looked. They saw no sign of human life nor any sign that humans had ever been, there. But after all, even five thousand years of mining on a globe six thousand miles through would not involve the disturbance of more than a fraction of its surface.
"We did it," said Kim. "The shield can be broken through by anything with a strong enough magnetic field. We won't disturb the local inhabitants. They undoubtedly have orders to kill anybody who incredibly man- t ages to intrude. We can't afford to take a chance. We've got to get back to Ades!"
He pointed the Starshine straight up. He d drove her, slowly, at the ceiling of impenetrable black. He worked upon the transmitter-drive relay. He adjusted it to throw the Starshine into transmitter-speed the instant h normal starlight appeared ahead. The ship swam slowly upward. Suddenly there was a momentary impression of reeling, dancing stars. Kim swung the bow about. "Now for Ades!" he said gleefully. "Did you know, Dona, that once upon a time the word Ades meant hell?"
The stars reeled again. . . .
They found Ades. Knowing how, now, it was not too difficult. There were two positions from which it could be detected. One was a position in which it was on a line between the Starshine and the sun. The other was a position in which the invisible planet of the space-ship, and the sun formed the three K points of a right-angled triangle with Ades in the ninety-degree corner.
Kim sent the little ship in a great circle beyond the planet's normal orbit, watching for it to appear where such an imaginary triangle would be formed. The deflected light of the sun would spread out in a circular flat thin plane, and somewhere about the circuit the Starshine had to run through it. It would be a momentary sight only, and it would not be bright; it would be utterly unlike the steady radiance of a normal planet. Such flashes, if seen before, would have been dismissed as illusions or as reflections from within the ship. Even so, it was a long, long time before Dona called out quickly.
"There!" she said, and pointed.
KIM swung the Starshine back. He saw the dim, diffused spectre of sun's reflection. They drove for it, and presently a minute dark space appeared. It grew against the background of a radiant galaxy, and presently was a huge blackness, and the Starshine's space-radio loop was once more filled with a highly improbable electrical amperage by the supercooled generator in the airlock.
The ship ventured cautiously into the black.
And later there were lonely, unspeakably desolate little lights of the lost world down below.