"Yes."

"Why did you come?"

"It is part of my duties."

There was silence between them. He turned to stare out of the quartz port-hole again. Jupiter was perceptibly nearer; an enormous, convex globe that blotted out half the heavens. They were being drawn at a frightful velocity toward the mysterious pulsating point, now blinding in its brilliance.

They both saw it simultaneously: a s.p.a.ce-suited figure, far out in the depths of interstellar s.p.a.ce, caught up in a sudden flare of orange illumination. The strange figure seemed to whirl around, straighten up, and shoot at breakneck speed headlong for Jupiter. Behind it, and in a direct line with the winking flame in the Great Spot, another s.p.a.ce denizen glowed luridly, startlingly, out of the blackness beyond, whirled, and shot down the long invisible path.

Nona cried out: "Grant, tell me quickly, what are they; what is pulling them?"

Even as she spoke, more and more figures were blazoned in that orange ray, until a long file of beings were catapulting in a single straight line past the s.p.a.ce-ship, outdistancing it until they became faint specks in the distance.

Pemberton's hand was upon her shoulder, his eyes literally blazing through the goggles, while his voice shouted in her ears. "Come with me: We haven't a second to lose."

"But," she gasped, "you haven't told me--"

"No time," he interrupted, and, shoving her in front of him, he rushed her through corridor after corridor until they came to the air-lock of the liner.

"If only we have time," he groaned, and cursed himself for a bungling fool for not having surmised the maneuver earlier.

Just as he had expected, the great lock was open. The ship was as silent as the grave. There was no air anywhere, only the unutterably cold airlessness of s.p.a.ce. Without pausing in his headlong rush, he pushed the bewildered girl through the open port, out into the overwhelming, intangible blackness. Nona's smothered cry of fear came to him as the next instant he stepped forward and left the solid footing to float in sudden weightlessness in a vast sea of nothingness.

The girl reached out and caught his arm convulsively. Even through the fabric of their suits he could feel her trembling. Pemberton had taken good care to retain a hold on the edge of the open air-lock. The two swung unsteadily.

"What is the reason for this?" Grant sensed, rather, than heard, the tremor in her voice. She was making a desperate effort to control herself. "We'll be lost--out here in s.p.a.ce."

"Don't worry," he said soothingly. "I'll explain in due course. In the meantime you'll have to trust me. Did you see where that invisible ray held when it illumined the last Ganymedan?"

"Ganymedan?" she echoed in surprise. "What makes you think--"

"Never mind that. Did you?" he insisted.

"Yes," she admitted, "it was about over there." She indicated the spot with an outthrust arm. "About a hundred yards, I should judge."

"Exactly," he agreed. "Well, young lady, our lives, and far more, depend upon our reaching that exact line in s.p.a.ce immediately."

"I don't know what you are talking about, but even so, how can we make it? I'm not a rocket."

"It's difficult, I admit, but we must. Now hold on tight to my arm, and press your feet firmly against the wall of the ship." She obeyed.

"Now when I count three, shove off violently, and pray that we're going straight. Are you game?"

She stiffened; then, very slowly, "All right; start counting."

"Good girl," Grant said approvingly. "One--two--th-r-ee-ee!"

They flexed their legs in perfect unison. And shoved off.

Out into the blackness of s.p.a.ce they shot, lost to all sense of motion: yet the hull of the s.p.a.ce-flier, dimly gleaming in the thin light of the far off sun, retreated from them with terrifying swiftness.

They were alone in s.p.a.ce! It was an uncanny, a horribly helpless sensation. All about them was infinity, a vast void out of which peered at them the cold, unwinking stars. They were like swimmers in mid-ocean, without even the buoyant feel of the salt water to comfort them.

Nona's grip on Grant's arm was agonizing in its intensity.

"Scared?" Grant queried.

"A--a little," she admitted; "but don't bother about me. I'm all right."

She could be depended upon to keep up her end, Grant thought admiringly.

On and on they floated in the welter of s.p.a.ce. And still there was no ray, nothing but unrelieved blackness. Pemberton was somewhat worried.

Had the saving ray been quenched at the source? Were they too late? If so, they were doomed to a frightful obliterating fall to the surface of the planet, or worse still, they were destined to swing endlessly in s.p.a.ce. Already the liner was far away, out of their grasp, even had they desired to return.

His breath was coming in quick gasps now. "Scared?" he once more asked the silent figure beside him.

"Frightfully--but carry on. We'll get there, wherever it is."

Her gay determination strengthened him wonderfully. On and on they floated.

Suddenly the dim, dark bulk of the girl caught the uncanny orange light. The next instant the creatoid fabric of his own suit caught it, too.

"Thank G.o.d," he cried joyously. "It's still on. Just relax, Nona, the ray will take care of us now."

He felt a powerful tug at his body, he was whirled completely around, and then there was a steady pull. He was being catapulted down the ray to the mysterious point of brilliance in the Great Red Spot. The girl was right beside him. The s.p.a.ce-liner was pa.s.sed with a smooth rush, and soon receded to a dwindling speck.

"Now will you explain?" asked Nona impatiently, after she had caught her breath in sudden relief.

Grant stretched luxuriously before he began.

"Certainly. There's nothing for us now to do but wait until we get pulled down to Jupiter, and that'll take some time. I hope we look like Ganymedans."

"Will you get on with your story!" she cried.

He obeyed. He started from the beginning and went right up to the time when he had so rudely thrust her out into s.p.a.ce.

"You see," he explained. "I had put the puzzle together a bit, but there were still pieces missing. For instance, those chaps down there know that every s.p.a.ce-liner is equipped with emergency s.p.a.ce-suits.

Why pull the ship down with live men on board? That would naturally mean a fight, and we have no mean weapons, what with disintegrator ray-projectors and explosive electro-bullets." Then, again, for some reason, there were Ganymedans on board. They would very likely be whiffed out in the melee. The ship might be destroyed also, and they evidently are very careful about getting the ship down intact. The little meteor holes can easily be plugged up, and the liner made as good as new. At least that was my guess.

"I was trying to puzzle it out, rather hopelessly," he continued, "when I saw the ray out in s.p.a.ce pick up those floating figures. That was the last little piece in the jigsaw.

"The Ganymedans evidently had to leave the ship because, as it approaches the planet, something will be done to kill off any unfortunates who are still alive, waiting their chance to fight the invisible enemy. Possibly a penetrating lethal gas that will be forced into the interior. So they evolved the ray to carry the Ganymedan pa.s.sengers down gently, safely. And we are stowaways," he concluded grimly.