Early the next morning the boys were clamoring to get started, but their mother would not let them go into the control room.

"Now you listen to Mother," she protested, using a favorite phrase of hers. "Your father hasn't made any sign yet. You wait until he's awake and has had something to eat. I know how anxious you are to do all these things, but you must remember he isn't strong yet, and we must not let him overdo. He is as much a child about such things as you two are, but someone has to watch him."

The boys laughed rather shamefacedly. "It's just we get so interested in things, Mom," Jon apologized.

"Yes, I know. But if you will look in your dictionary, you will find a word called 'moderation.'" She smiled.

"Never heard of it." Jon grinned as he went to get a reelbook on radioactives, and began studying. Jak, too, went back to studying and trying to classify the various specimens he had obtained from the two worlds. However, they soon remembered their usual duties—and whisked through their various chores about the ship, then went back to their absorbing occupations.

They had been at these nearly an hour when they heard their father's voice. Dropping everything, they sprang toward the control room, and found him wide-awake and looking much better. Mrs. Carver came running in, and they were told, "Feel fine. This is a wonderful bed. Seem to be much stronger today, too."

"That's wonderful, Mr. C. I'll go get you some breakfast."

Jon ran for a basin of water and towels, and he and Jak helped their father with his toilet.

"While you're eating, Pop, how about me cutting off that piece of the new metal so we can start studying it?"

"How big a piece were you figuring on?" Mr. Carver asked with that quizzical look.

Jon flushed and mentally changed the size he had planned to get. "About a gram?" he asked.

"I'd say more like a few milligrams." His father grinned. "That's plenty for our initial studies and analyses, and shouldn't hurt us any if we're careful and wear insulation."

"But that's only a pin-head size."

"Well?" again quizzically.

Jon flushed once more. "Yes, that's big enough to test, I realize now. It's a good thing I waited for you to help me. I'd probably have burned myself but bad. Actually," he smiled now, "I was figuring on about a quarter of a pellet."

His father frowned. "You should have known better than that, Jon. I thought I'd taught you something about being careful, and the dangers of rashness or impulsiveness. Especially around anything as dangerous as this stuff undoubtedly is."

"You did, sir, and I'm sorry. But I forget sometimes, when I get too enthusiastic."

"Well," philosophically, "you'll probably learn as you grow older ... if you live that long!" But again there was that disarming grin, which Jon repaid in kind before leaving to get his tools and go after the mite of new metal. This time, he did not neglect his precautions. He wore his suit, and put on a pair of extra-thick, lead-impregnated gloves.

Carefully he lifted a pellet from the box, wrapped it in several layers of lead foil left after making the box. He carried it so into the storeroom, locked it in a vice, and with a fine hacksaw cut off a tiny bit. Still wrapped carefully in the lead foil, he carried the remainder of the pellet back to the box in the lock, closed the lid and then took the sample inside. He took off his suit and donned a lead-impregnated, hooded gown and the leaded gloves.

"Good," his father said when Jon told what he had done. "I think I feel well enough to sit up a bit. Suppose you crank this seat halfway up, then I can watch better while you make the tests."

"Just be sure you don't get too tired," Jon said solicitously as he raised the seat and locked it at half-recline. He had brought in another of the leaded-gowns, and he slipped this over his father's head, arms and upper torso, arranging the balance of it down over his blanket-enwrapped legs.

Then, acting on his father's various instructions, he took the particle from its wrappings and began his tests. He measured the amount of radioactivity, and together they computed its half-life.

"Wow! That sure is high-pressure stuff," Jon exclaimed when they had completed the various tests which they had the equipment to make.

His father silently motioned him to set the seat back to full recline and lay there, concentrating, for some time before he spoke.

"Yes," he said at last, "it's even higher in the scale than I thought. Lots higher than Curium, even now. And no telling, by any tests we can make, what it was originally, before its many half-life reductions that must have taken place over the long time it has undoubtedly been lying out there. Probably way above anything known, even theoretically, to Terran scientists."

"Can we use it?" Jon was quivering with excitement.

"If we can figure out a way to do so safely, so it doesn't want to disintegrate all at once, I think we've really got a fuel—a super fuel. But we'll have to go at it mighty slow and easy. That stuff could blow us higher than up, if used wrongly."

"Yes, I know. But after our scientists first liberated atomic energy for their bombs, many people said they couldn't control a hydrogen bomb, but they did. And later the thorium bomb. And then they got our activated copper. So I'm betting they can figure this out."

Both fell silent, although there were a dozen eager questions the boy wanted so much to ask. But he did not interrupt his father's line of thought, even though long, long minutes dragged away while the elder still pondered the problem.

At last, after more than a quarter of an hour, Tad Carver stirred and looked up. "This is going to take a long time to figure out," he said slowly. "I'm not too much on atomics, myself, and neither are you. Now you run along and do whatever else you have to do. It's a cinch we won't be able to try this stuff right away—if we try it at all."

The disappointment on Jon's face was plain, but he restrained any protests, knowing his father was right, and not wishing to call down on himself another verbal chastisement like that recent one.

"What about the rest of the stuff?" he asked instead. "Shall I get the box out of the cache and weld it onto the hull, as we thought we might do?"

"I don't see why not. We want to take it back to Terra with us, whether we figure out how to use it, or decide the job's too big for us and turn it over to the scientists there to handle."

"Right." Jon went over to the controls of the handling arms in the lock. Watching in the special visiplate, he opened the outer lockdoor, extended the "hands" and guided them down into the cache, after using them to lift the lid off the larger pit-box.

Carefully he manipulated them to grasp the inner box by its lower end-edges, and experimentally lift it an inch or so. Finding that it balanced, he slowly made the servo-mechanism lift the heavy container from its ages old resting place and up onto the "top" surface of the ship, near the stern. Making sure it was securely held there, he put on his suit, gathered up his welding outfit, and went outside and climbed onto the hull.

Going to where the box rested, he began the task of welding its bottom back-edge onto the metal hull. Then he released the grip of the handlers and, leaving them dangling in the air, welded the other three bottom edges.

Finished, he turned off his torch, rose to his feet and started back. But after a step or two he stopped and thought.

"Pop," he said into his suit-radio, "do you hear me?"

"Yes, Jon," the answer came back at once into his earphones. "What is it?"

"I was just wondering if it wouldn't be a good idea to spot-weld a few places along the edges of the cover, too, so there'd be less chances of its coming open. It'd be easy to open it later."

"How's it fastened now?"

"Just a simple hasp."

"Better touch it in a few places, then, to make sure."

"Right."

When this was done, Jon returned inside the ship, and saw to it that all the equipment was put back in place and carefully locked. Only then did he doff his suit and return to the control room.

"Well, that's done. What now?"

"Anything else you need to do here on this planet?"

"No-o-o, not that I know of. Why?"

"I was thinking that if everything has been taken care of, we might as well start back to Terra. No use staying any longer than is necessary."

"I ... I think we've done everything. Have you checked the record book and the pictures?"

"No, not fully. And I probably should, before we take off, at that. But I think I'd better have another nap or rest now, so I'll go over them after a while. Put them on the table here, so I can reach them."

"Right, sir. You take plenty of time to rest. If Jak's not too busy to go with me, I think I'll go fishing in the river, out there by the edge of the desert. Maybe we can get quite a haul to take with us, for fresh food on the trip."

"Good idea. Your mother said they were delicious."

When the two boys returned with full creels late that afternoon, they went at once to see how their father was getting along. He was awake, and studying the records they had made.

"Hi, fellows! Everything seems to be in fine shape. You chaps certainly did a job while I was non compos. Get any fish?"

"Lots of them. They sure bite swell here. Maybe because no one has ever fished them before, and they have no idea of lures and hooks."

"Then let's just rest and eat and sleep, and plan to take off in the morning, eh?"

"You bet. I'll sure be glad to get back home again," Jak declared. "This chasing around is fun, but I'm homesick for Terra, I guess."

"Me, too, kind of. Besides, I want to get some more schooling at one of our atomic institutes," Jon added more slowly.

"Going to give up inter-stellar exploration, Son?" his father asked drily.

"No, sir. But I figured we'd have to stay on Terra for a year or so while you get everything straightened out about this discovery, and get the ship ready for the next trip. So while you're doing that, I might as well be trying to learn something more."

"We will, and you should. And I presume," he turned to face Jak, "you want to study medicine?"

"That, and other things," the elder boy responded soberly. "If we can afford it, sir, I'd like to get several top men in various branches to give me some special coaching, instead of going to a school. That would get me started straight, and they could recommend good books for me to be studying while we're on our future trips."

Their father looked up at his wife with a smile. "What's happened to our babies, Marci?"

"They've just grown up, Mr. C.—but we have some pretty wonderful men in their place." Her eyes shone. "It was pretty hard, at first, after you got hurt and they had to take charge of everything, to realize that they had grown away from us. But I soon found that they hadn't, really," she continued hastily as the boys gave cries of dismay. "They have matured wonderfully, but we have not lost our boys at all."

"Well I should say not!" Jak cried hotly.

"We're still kids, not men," Jon declared. "Why, there's still so much to learn—and experience to gain—we've barely started growing up."

"You can keep learning back on Terra," their mother said. "As for me, I'm glad we're going to be there a year or more. I want to live in a house again, on land I know."

"Then we'd all better get to bed," their father said with his old-time roguish smile. "Otherwise we'll all be too fagged out to take off for home tomorrow."

---

As soon as breakfast was finished the next morning the Carvers all assembled in the control room for the start back to Terra.

Jon had already made the astrogational calculations for their trip, having worked on them off and on during many evenings of the past several weeks.

But just as they were all strapping down, his father stopped Jon with a sudden exclamation. "Wait, Son! I think we'd better go back close enough to all the planets and the sun to make sure all the signals are working right. That's one of the most important things the Colonial Board will check."

"Oh, I'm sure they're OK, Pop. We listened to each one after we'd placed it."

"But cases have been known where a sender failed—especially those on extremely hot or exceptionally cold planets. I'm not doubting that you handled them all right—it's just that I think it worth the time and effort to check them and make sure while we're still out here."

"All right, you're the captain." Jon opened the drawer in the control desk and hunted out the sheets on which he had figured his former flight plans to the various planets.

"We won't need to land if the signals are working," his father said. "Just get us close enough in line so we can receive the messages."

"In that case, we can fly almost by sight, merely taking into consideration the direction and speed of the planets." Jon shoved his papers back into the drawer. "Let's see ... we'll make the best time going to One, then the Sun, then Three, Four and Five, and then circling about and heading for home."

"Fine! Get going."

"Strap down, everybody."

A quick glance to see that they were all secure, then Jon closed the master switch of his new interlocking controls. Smoothly, with increasing acceleration, the Star Rover lifted upward through the atmosphere on the planet Marci—Carveria Two.

Ever more swiftly it flew, and a special sort of gladness was in each heart at the thought that soon they would be once more speeding toward their home on far distant Terra.

Traveling about the universe, seeing new suns, new planets, new and interesting—even though alien, and sometimes dangerous—forms of life of various kinds, all this was a constant source of interest and delight. Still there was within each of them, even Tad Carver, a love of and a longing for the planet that had given them birth. Men had always found it so—it was probable that men born on Terra always would. Probable, too, that men born on other planets would always long for a return to their mother world.

It took a special type of person to become a colonist on another and alien planet. Much the same type of pioneer as those great-grandparents, many times removed, who had made the terrible journey across the western plains and mountains of Noramer to conquer the great, wealth-producing West, and their forefathers and mothers who had braved the perilous and unknown oceans to come from the Old to the New World in Colonial days, to search for freedom and opportunity.

It had been found that, even among those willing to make the sacrifices and uprootings necessary to become colonists on other worlds, there were always a few who realized they could not stand it, after all. These unfortunate people usually returned to Terra—if they had the funds to do so. Nor did it seem to matter how much this new planet was like Earth, nor how great the opportunities for gaining wealth and prestige. It was that inner feeling of always remembering that they were so far from home and everything and everyone they had formerly known and loved.

Tad Carver was a true "son of wanderlust." He had the itching foot; the urge to travel; the zest for new places, new scenes, new outlooks. But even he, after a certain time away, felt that indefinable yet exceedingly strong must to return to his home world for a while.

The boys were young, which meant they were eager for new experiences, whether on their own or other worlds. They had not yet come to an age where Terra meant a great deal to them. Life was so thrilling, so interesting—there was so much to see and do. Yet even they did feel nostalgia after too long an absence.

It was Marci Carver who felt it most—this longing, this need for the old home. While it is true that her great love for her husband and sons made "home" for her any place in the universe where they might be, yet she had no real interest in exploration, no great desire or even curiosity to see other lands or other worlds. The deeps of space brought such an awe to her that they almost made her afraid. No, if her menfolk had been satisfied there, she would never have dreamed of leaving Earth. She would have been perfectly content to live in one town or city all her life—in the same house, even. She did not have the pioneer spirit; did not in the least desire new scenes. Her home and her man and boys—these were all she asked of life.

Yet she did have the rare knack of making any place where she might be, home. She could make a mansion or a hovel—or this spaceship—seem such a perfect home to her men that they were perfectly happy and contented with their living quarters. It was not a matter of furnishings or their arrangement—not just material things like pictures, books, pillows or other knickknacks placed just so. Rather it was the "spirit of home" with which she impregnated every place in which her family might be living at the moment.

The boys had not yet noticed this consciously—they were so filled with the joy of living and doing and learning that they had not yet stopped to think about such matters. But Tad Carver recognized it, and loved his wife all the more because of her ability.

He often remarked of her, "put her in even a hotel room for ten minutes, and she'll make it home for me." He sometimes felt moments of guilt that he made her chase around so much, instead of letting her stay in one place—and remaining with her there. But he could not stay put—and he knew she would not want to remain any place without him.

That was why he had arranged things so she and the boys could travel with him. And, until he had been hurt and she, with the boys, had had to take over his duties, she had seldom left the ship while on other planets, although she always looked out through port or visiplate in the various places where they had gone, with the keen interest in anything new that made her such a delightful traveling companion.

So now all four felt that eagerness to be done with this matter of last-minute re-checkings, so they could be on their way back to Terra. It made the time pass swiftly—yet made it so draggingly prolonged, it seemed they would never reach their destination.

The ship soon reached an acceleration of two Earth gravities, and Jon asked, "Is this fast enough, Pop, or can you stand more?"

"You might step it up to three G's for an hour. There's no use loafing around here longer than necessary to make the curve so we can come fairly near each planet on the line between it and Terra."

"And that'll get us up to cruising speed quicker when we do start the straight stretch for home," Jon said, and turned back to his controls to apply another notch of speed.

It was not long before they approached Planet One—"Tad." Jon had plotted a course that would take them to within about thirty thousand miles of the little, hot planet, on the Earthward side. As they flashed past it, their receiver clearly picked up the broadcast of their signal-unit.

"That one's all right," their father said in a pleased voice, and Jon looked up and back from his calculations on the orbit to circle them about the sun, to grin his pleasure at the approval.

"Jak put it on top of a peak in the intermediate zone," he explained. "The weather—if you can call it weather—there is more nearly normal than either on the sunward or the spaceward side."

An hour later Jak struggled up from his chair, staggering beneath the triple weight of his body at that acceleration. Seeing him, Jon called, "Wait, Owl, I'm just about to reduce to two G's." And in a moment the older boy found it easier to get the sandwiches and bottles of nourishing broth their mother had prepared before take-off, and distribute them to the others. Gratefully, they all ate and drank.

"After we circle the sun and are en route to Three, I'll cut down to one gravity while we have a real meal," Jon promised.

"Aw, let's not slow down just for ..." Jak began.

"It won't cut our speed, just our acceleration, which means 'constantly added' speed," his father explained good-naturedly. "As soon as we've passed them all and are heading for home, we'll cut to one gravity for the greater part of the trip, but our speed will have been built up tremendously."

"Oh, sure, I know that, but I forgot for the minute."

As they circled toward the sun Mr. Carver studied it carefully in his visiplate. "Just about the same type of sun as Sol," he said after a while.

"That's what I figured, only that it's about one quarter larger and heavier," Jon told him. "I was hoping you'd be well enough before we left to check it for me."

"How close did you set your signal-sender orbit here?"

"Ten million miles."

"Ten million!" The man gasped, then laughed in relief as he thought the boy was just trying to spoof him. "Oh, come off it, Jon. How far out were you, really?"

"Unless my figures are all wrong," Jon's voice held a hurt note, "it was really only ten million miles. You can check my calculations. The book says quote said orbit to be as nearly circular and as close to the discovered sun as possible unquote, so I sent us in on a van Sicklenberg throw-out orbit apexing at ten million."

"Boy, that was really taking a chance. You don't need to repeat it for my benefit."

"I wasn't planning to, sir." Jon grinned now. "We'll go around at about twenty million this time, but the same type of orbit as before."

"That's better. Well, I think I'll go back to sleep. All of us should, I suggest."

"Mother has already dropped off," Jak said softly, glancing toward the recline seat in which she lay. "Switch on the auto, Chubby, then douse the glotubes. 'Night, Father."

And soon the little ship was speeding across the interplanetary wastes, guided only by the automatic pilot, while inside four weary people slept peacefully, knowing the mechanisms would guide them safely and surely to their distant, plotted destination.

For, outside of a possible recurrence of the accident that had caused Mr. Carver's injury—and that was a billions-to-one chance that could not possibly strike them again—what was there to fear away out here?

Nevertheless, it was the sudden ringing of an alarm bell that woke them all into instant, wondering wakefulness.

---