Later that evening Jon Carver sat for nearly an hour, studying intently from one of his reelbooks, and the frown on his face grew deeper and deeper.

Jak had been working over their father. He had given him a careful sponge bath, then fed him another intravenous dosage of the combined liquid protein, salt, sugar and glucose. Even though their mother had been able to spoon-feed her husband small amounts of food each day, the young hoped-to-be doctor felt additional nourishment was necessary.

When he finished his task and started to seek a comfortable seat in the living quarters of the space yacht, to relax with a little reading of his own, he noticed his brother's intent look and worried face.

"What's the matter, Jon?"

"Eh?" The younger boy looked up, startled, from his deep study. Then, as Jak repeated the question, he answered unhappily, "I just don't know enough, Owl. I can't figure out why Pop found such strong spectroscopic lines of that new element while we were billions of miles away, and yet we can't find any traces of it anywhere on these planets, except what we found in that cache."

"Maybe it's in the sun."

"I tried that when we were out there, but 'Annie' didn't even peep."

The elder brother studied the problem a moment.

"Could it be so strong that even the little bit we found would have shown those lines?"

"Maybe," doubtfully, "but I don't think so. Tomorrow morning, when the sun comes up, I'm going to try to take a new reading from here. I tried to read Two, but couldn't get anything. However, I'm not so hot with the regular spectrograph, and that's why I'm boning up on it."

"Is this important?" Their mother had laid her sewing in her lap to listen to them, trying to follow and understand what her sons were talking about.

"Pop thought it was, Mom," Jon explained. "One of the things men have been looking for ever since they first started dreaming of rockets and spaceships, was the best possible fuel. We knew the one we're using now isn't the ultimate, but it's the best they've been able to get so far. Pop thought perhaps this new stuff might be it—if we could find it, and if we could learn how to use it."

"Why can't we use it if you find it?" Jak wanted to know.

"There are so many problems. Maybe it would be so radioactive we wouldn't be able to handle it or keep it in the storage bins without endangering the people on the ship. Maybe the exciters and convertors wouldn't handle it without a lot of new experimenting and new designs we wouldn't have the scientific or technical know-how to make. Or it might be that instead of getting a steady stream of power as we do with our present activated-copper fuel, the stuff would want to blow up all at once. If the metal's as powerful as I think it is, it might cause an explosion that would make man's biggest H- or C-bomb look like a firecracker."

"Then don't you go experimenting with it and blow us all up," his mother said sharply.

Jon grinned at her. "You needn't worry about that, Mom, now that I've had a chance to learn how little I know. Although I would've gone off half-cocked that day you stopped me—for which I'm grateful, even though I was sore at you for a while then. But I'm sure going to study it as soon as we get the other markers set and can get back to Two."

"By that time Father will be well again," Jak said.

"Isn't it wonderful that he really is coming around all right? Seems to be taking an awful long time for him to recover fully, though."

"I'm sure he'll be his own keen self again soon ... although he'll have to stay in bed until that leg is strong enough to stand on again."

"Well, let's hit the sack, so we can get a good start in the morning. 'Night, Mom."

---

During their journeys over the surface of Planet Three the boys conscientiously tended the machines and recorders that gave them the data on land and water conditions, the proportions of each, the approximate amounts of metallic ores their analyzers showed, the information on weather, temperature and humidity. They took numerous pictures as required by law—their mother often helping in this, after Jak had taught her how to operate the cameras. These pictures Jak developed and printed as he had time, and mounted them in their data book for the Colonial Board to study when they got back. They also mapped and recorded the size and distances of Three's two moons.

Jak named these "Zinnia" and "Begonia," much to Jon's sarcastic and openly-expressed derision.

"This'll make a swell home for people who like cold weather." Jak tried to change the subject.

"Yes, just as Two will for those who like it hotter." Jon's eyes shone. "Pop sure picked a winner when he decided to explore this system. Even with just these two worlds he has a prize."

"If they accept our work as proof. Wonder what the fourth planet will be like?" Jak continued in a different tone.

"Cold. Lots colder, probably, than Mars."

"Then it won't do us any good?"

"Depends on what's on it in the way of metals that can be mined. Maybe we'll find something there. Might be natural gems or jewels, too."

"And anyway, cold never stopped man."

"That's right," Jon said admiringly. "They have mines on Pluto, even—although they're mostly worked by automatics while the men stay warm in their bubble-cities."

As the Star Rover approached closer to the distant, smaller planet they had named "Jon," their instruments showed it to have a diameter of about 4400 miles, and a density of about 4.6, a little lighter than Terra. This meant the gravity would be a bit weaker, and they would weigh less than on their home planet. Four was almost a quarter of a billion miles from the sun, and would be very cold, as Jon had said.

While their ship drove in closer, the boys' mother came into the control room. All three Carvers stared excitedly into their visiplates, watching their rapid approach to this new world. Would they find anything of value there, or was it simply a barren wasteland of ice and frozen air and rocks, far too cold and forbidding for men even to bother trying to explore it?

When Jak, eyes still glued to the telescopic sights of his spectro-analyzer, voiced something of this, Jon drawled, "You know better than that, Owl. We said just yesterday that there's no place, no matter how bad, that man won't explore to see if there's anything he can possibly use. They'll follow us here, don't worry."

After cruising about the surface for some time, recording their data and taking the needed pictures, they saw a fairly level valley, ice-covered and bare, and Jon set the ship down there. By now he was becoming an expert astrogator and pilot, and with his new controls they could hardly feel the jar of the ship's landing.

"How's the temp outside?"

Jak was examining the gauges. "About a hundred below, and not a bit of moisture, naturally. Going to try going out?"

"I don't...." their mother started to speak against it, but made herself stop. Her boys were showing such resourcefulness and unexpected habits of caution that she felt she must let them decide things for themselves, even though her motherly instinct was always to hold them back from possible dangers.

"Sure we're going out for a bit," Jon answered his brother, then faced their mother. "It'll be all OK, Mom," he said affectionately. "We'll wear our suits, of course, with the heaters on. We won't go far, because the moment we feel any cold we'll run back. But I want to see what it's like out there, and if there's any sort of life. We're supposed to report...."

"Life? Here?" incredulously.

It was Jak who answered this. "Sure, Mother, there can be life-forms anywhere. Oh, not necessarily nor even probably anything we know on Terra. But there should be some sort of moss or lichen in the plant line."

"Yes, it has been learned from experience there's some sort of life almost everywhere," Jon chimed in.

"Even though most of it's so different from the basic protoplasm-type we're used to that it's hard to realize it's really life at all," Jak continued. "But then, remember back on Terra, the vast difference between animal and vegetable life—so totally unlike each other. I second Jon's plan to go out. I'd really like to see what's out there."

She sighed as if in recognition of the fact that these boys of hers were fast becoming reliable, self-sufficient men. They were not her babies any more. She was proud, of course—but she couldn't resist the motherly impulse to warn, "Well, be careful, anyway."

"Sure, we will."

Jon locked all the controls in neutral, and the two boys went to put on their suits. Knowing, as they did, the vital necessity of making sure they were "tight" and fully equipped, they examined and inspected their own and each other's spacesuits carefully before they opened the inner lockdoor.

Once outside, they stood on the icy ground for several minutes to make sure their heaters were working capably enough to keep them—and especially their feet—warm. Finding they were as completely comfortable as anyone ever can be inside that sort of a suit, they started off across the frozen plain, headed for the near-distant hills on the side of the valley closest to the ship.

Jak examined the ground about them intently as they walked, hoping to find some sort of plant life, while Jon kept his eyes mostly on the portable analyzer he carried, hoping they might discover valuable deposits of inorganics. Was there any of that unknown fuel-metal here, he wondered anxiously. Their big analyzer had not shown it as they were coming in on the survey or landing spiral, but that did not necessarily mean the portable wouldn't show it on closer approach, or that there might not be some on a portion of the surface they had not yet covered from above.

Their trips about and above the surface had, however, shown traces of iron, manganese, gold, silver, copper and several other metals, although not strongly enough to indicate great deposits. But Jon knew experience had shown over the years that one of the inefficiencies of such analyzers was that they would not show the depth of a deposit. Many times, when only a slight trace had been detected while flying above the surface, prospectors on the ground had found veritable bonanzas, once they started mining.

Even though the gravity was about eight per cent lighter than on Terra, the boys found walking not too easy. The terrain was mostly rough, although there were many spots of slick, glare ice. Too, there were many hillocks, and cracks and crevasses between the slippery places. So, even though they had added caulks to their metallic suit-boots, walking was unsafe and hard. By the time they reached the base of the first low hills they were winded and glad to rest a few minutes.

"Not a thing so far," Jak panted into his suit-mike. "I can't see even a bit of color—just this white glare."

"'Annie' hasn't let out a peep, either. Guess this is a dead 'un all right."

"At least this district looks it."

"Let's climb a ways, and if we don't find anything there, go back to the ship and try somewhere else."

"I'll buy a chunk of that."

They started up the hill before them. The climbing was difficult because of the ice and because in most places the side of the hill was not a gradual slope, but a starkly steep climb. It was evident there had been no gradual "weathering" here, to produce rounded edges and rolling slopes, although there were occasional smooth places. These, though, the boys knew could not be climbed at all without special equipment which they did not carry.

"This isn't frozen-water ice, is it?" Jon asked as they panted upward.

"No, silly. There can be no water vapor here, any more than there is on Neptune or Pluto back home. This is mostly frozen carbon dioxide."

"Well, it's just as cold and just as hard to climb as polar ice."

They climbed the quarter mile to the crest of the first hill and peered eagerly over its top. In front and slightly below was another valley—not as deep as the one in which their ship lay, but even larger. From their higher position the floor of this new valley seemed quite smooth.

"But that can be just an optical illusion," Jak answered Jon's statement, adding, "the glare of white would make it look smoother from a height."

Jon ignored the tone of superiority. "Good thing our suits have tinted lenses. Do we go down?"

"Natch." Jak had already started. "Off there to the right and part way down are some darker places. I want to look at them."

"Could lichens grow here?"

"Some could, possibly, though not exactly like the kind we'd find on Earth. If there's life here, it's probably a type that can convert energy directly from the elements in the ground or ice, instead of using photo-synthesis or other methods of obtaining nourishment we know about."

Half-sliding, half-climbing, they made their difficult way to the little patch of gray-greenness, which Jak examined with growing delight.

"Hey, that's gneiss."

"What's nice about ... Oh!" Jon grew red-faced at having been caught that way. "You and your education!" he snorted.

"See how brittle it is," Jak ignored the interruption as he touched a stem, only to have it snap off like a slim glass fibre. "Can't tell without a more thorough microscopic examination, but I'll bet this is some sort of silicon-based life—crystalline instead of being like the gneissic rocks back home."

Jon, meanwhile, had been surveying the valley with his binoculars. Suddenly he gave a gasp, and focussed his glasses more steadily on something that had caught his eye.

For some minutes he studied it, then called excitedly, "Hey, Owl, give a look over there. See, beside that spire of rock," he pointed as his brother rose and unlimbered his own pair of binoculars. "There's movement of some sort there, though it's very, very slow, on that sort of pyramid a yard or so high."

For long moments the two studied the spot through their high-powered glasses, then Jak said slowly but with mounting excitement, "I think you're right, Chubby, and that we've got to see."

In their excitement, the two started off faster and more carelessly than was safe. They found out that fact when both, almost at the same time, lost their footing and fell, coasting down the remainder of the hill. Faster and faster they slid, shaken and becoming bruised, although luckily neither broke any bones.

At the bottom they picked themselves up and started on again. Both walked more gingerly now, and Jak limped a bit from a twisted ankle. Yet they were so eager to see what this strange movement might be, they soon forgot their bruises and hurried once more.

It was a good half mile across the valley floor to their destination. But there, sure enough, they found life!

Strange, unearthly life it was, but they soon discovered that it had reproduction, growth and movement—the three main criteria of life-forms.

"Crystalline, by golly!" Jon yelled.

Jak was squatting beside the growing thing. It was somewhat pyramidal, yet the sides were not smooth. Rather, they were many-faceted, like the pieces of rock crystal with which the boys were familiar. It was a grayish-white color—with just enough of the gray in it so it had been visible from a distance, against the white background. But now, as the boys were on the sunward side of one of the pyramids, for there were many of them about, they could see that the light reflected from it was kaleidoscopic coloration at times.

Jak reached out a gloved hand and rapped on the pyramid ... and it gave forth a tinkling sound, then collapsed into a thousand tiny shards.

"You ... you broke it."

"Yes, I'm sorry. I didn't mean to kill it. Had no idea it was so fragile." Jak rose, moved over to another pyramid, and squatted beside it, examining it closely, but careful not to touch it. Jon sank onto his heels beside him.

For a few seconds as they watched there was no change. But suddenly they heard a small, clear ping, and a new crystal sprang into existence near the base. Almost at once there was a repetition of the sound and another appeared further up on the adjoining side of the structure—or creature. As the boys continued watching this was repeated over and over—with each tiny sound a new facet came into being somewhere on the pyramid. Before their very eyes the crystal-being was growing.

"Boy, that's something!" Jon exclaimed admiringly.

"Yes, it's a life-form, all right," Jak said more seriously, without taking his eyes from it. "It's all new to us, but I'll bet there's silicon of some sort beneath this carbon-dioxide ice, and that this thing gets its nourishment from that."

"What makes it keep growing?"

"What makes a man or an animal or plant grow when it eats?"

"Oh!" Then, "Do you suppose it has any mentality?"

Jak was silent a moment, mulling that over. Then he looked at his brother, a crease of concentration on his forehead. "I feel quite sure that it probably has, but of a sort we wouldn't be able to understand, even if we could get in contact with its so-called 'mind.' Even reading that, I doubt very much if we'd be able to understand its way of thinking, reasoning, or the motivations by which it lives." He went back to studying the strange crystallization.

"Ummm, probably you're right," Jon agreed after some thought. A moment later he asked, "Is it good for anything? I mean, can man use it for something?"

Jak wrenched his gaze away from that astounding growth to look up in shocked disgust. "Is that all you think about in the face of such a marvel as this—whether it's worth anything or not? Here we've found an entirely new type of life, and...."

"Hey, keep your suit tight, Owl. We have to report this, you know, and I'm just trying to find out what to write down."

"Oh!" Jak spoke slowly, his voice now admitting the lightness of that point of view. "I can't, offhand, see any practical value, especially considering how easily these crystals are broken. But I know geologists—and possibly chemists—will be intensely interested in studying them. There's a lot they can learn here, I'm sure. We'll naturally report all that, you're right, and the location of this valley."

"Think they may occur all over the planet?"

"No telling, but probably if they can find the right sort of soil nourishment. We didn't see any while coming down, but they might've been there and we missed them, not expecting anything like this."

"We didn't see any other life-forms, either, that we could recognize. Maybe these're the dominant species here."

Jak rose to his feet and looked all about him. There were hundreds of the pyramids to be seen, some towering a dozen or more feet high and as large across each base line; others very small—babies, he thought with a grin.

Again he watched one of the smaller ones intently, noticing how it grew. Jon walked about, looking at the different structures of that mysterious, growing crystal.

Suddenly he stiffened, straining, listening. Then he called, "Hey, Jak, you hear anything?"

"Huh?" his brother tore his gaze from the crystallization he was watching. "Hear what?"

"Turn up the power of your suit receiver. There. There it is again.... Hey, sounds like our siren!"

"Yes, I heard it then. Mother must be in trouble, or something."

Jak's last words were flung back across his shoulder as he ran as fast as he could across the icy wastes of the valley floor. Nor was Jon far behind. In fact, after a few strides the younger, but longer-legged boy was beside him, then forged ahead.

"Hurry, Owl! Mom wouldn't signal unless it was urgent."

"Maybe Father's worse."

They tried to conserve their breath after that for running and climbing. Once Jon broke the silence. "Turn your oxygen a little higher, Jak," he said as he twisted the small lever at his own shoulder to increase the flow of the strength-giving energy.

They were panting and winded by the time they reached the top of the hill. But they disregarded fatigue in the face of their mother's probable danger—or their father's.

Jon looked quickly to one side and then the other. As Jak topped the ridge he saw his brother run some twenty feet or so to where he had spotted a fairly smooth downward slope. Down this the younger boy launched himself feet first, sliding on his suit's back. Jak instantly realized the reason, and threw himself after his brother.

In less than a tenth of the time it would have taken them to climb down, the boys were at the foot of the hill. They struggled to their feet and started off toward the ship. Both were again shaken and sorely bruised from their rough slide, but they trotted on. Mother had called—nothing else mattered.

As they came closer to the ship they saw her reason for summoning them.

All about the outer lockdoor were those strange crystalline structures, growing swiftly. As the two boys came still closer, they could see that streamers of the crystals had already reached the lower edge and were trying to force their way through the almost imperceptible crack.

"They'll never get ... through there," Jon panted as he raced the last few feet.

"Don't see ... how they can ... but watch 'em." Jak waded into the alien, growing things. His gloved fists smashed right and left as he spoke. Jon was already doing the same.

But whether these crystal-beings were of a different type from those that Jak had broken in the distant valley, or just what was the reason, the boys now found it more difficult to break these crystals down.

"These aren't ... like those ... back there." Jon had now seen that these crystals did not always grow in pyramidal shape.

"No, they grow ... new crystals ... wherever needed." Jak had been concentrating on the tendrils, or chains of crystals that were reaching, always reaching, toward the lockdoor, while Jon had been trying to break the bases of the pyramids from which these arms sprang.

Although the crystals were still fairly easy to break—especially the tentacles, which were only a thin string—new ones replaced them so swiftly, and their numbers increased so constantly, that it seemed almost a losing battle.

"These're growing lots faster than the others." Jon gritted his teeth as he now tried crushing the bases with his heavy metallic boots, hoping thus to make it harder for the crystal-beings to reach the door.

For minutes the two boys fought in desperation; then Jon grunted in disgust at his thoughtlessness, and yanked out his flame-gun. "Never thought of this," he yelled as he trained it on the crystal-beings. The terrifically hot flame washed off them in coruscating showers—but did no damage.

"Try bullets," Jak unlimbered his gun from his back, and started firing it into the base of the crystals nearest the lockdoor.

The heavy bullets shattered the crystals easily, and soon the boys could begin to see that they were clearing the way.

"You keep firing while I open the door and climb in," Jon yelled. "Then you climb in while I'm going to the control room and I'll lift ship."

"Right," Jak replied and fired even faster as Jon touched the outer mechanism-stud that opened the lock.

Hardly had it begun opening, however, than they heard the sound of another gun being fired through the opening. They looked up in surprise and saw it was their mother, shooting a shotgun. Jon scrambled up into the lock.

"Good work, Mom, but get back in. I'm lifting ship."

He dashed through the inner doorway and into the control room. He threw the switch and Star Rover shuddered as its tubes roared into life. Jon punched on the intercom visiplate that scanned the interior of the lock, and saw his mother pulling Jak into the ship, then closing the outer door. Quickly Jon put the ship into a slow cruising orbit and switched on the auto-pilot. Remembering the open doors and the bitter outside cold, he glanced to see that the automatic heaters were taking care of the inside temperature, then ran back toward the lock.

There he found his brother desperately trying to warm their mother's unsuited body, now growing blue from that terrible cold.

"Help me carry her into bed." Jak rose and grasped her arms, but Jon pushed him aside. Stooping, he picked her up bodily. He ran, staggering a bit, with her into the bunkroom. Jak was right behind, and pulled some extra blankets from a drawer. Then, while he was piling covers about her, Jon dashed into the galley.

He drew hot water from the tap and quickly made a cupful of instant tea, then ran back with it to the bunkroom.

Some minutes later they saw with satisfaction that their mother's color was growing more natural, and her body tremors were slowing from the combined warmth of the extra blankets and hot drink. Only then did the boys stop to help each other out of their suits.

"Thanks for the help, Mother, but don't you know enough to wear a suit in weather as cold as this?" Jak's worry made his voice sharp.

"Yes, who's always fussing about us being careful?" Jon added. "Then pull a stunt like this."

Their mother looked up at them, and the old impish grin they had seen so seldom of late came onto her face.

"You've got me, Chums," she drawled. "From now on I reckon I'll keep my big mouth shut."

Jon howled, and Jak added in the same sort of drawl, "Well, now, I wouldn't go for to say it was 'big,'" and ducked as she slapped out at him.

Soon the two boys sobered down. "We'd better go examine the lock and make sure no crystals got in," Jak said.

"Yow, I forgot about that!" Jon sprang forward. "We sure don't want any of them in or on the ship."

---