time, onlycut-and-try methods were available for correcting his errors.

  Not even his prodigious and accurate memory could hold all the informationthat was necessary for the work, and there were no reference tapesavailable, of course.

  He had long since given up any attempt to understand the functioning ofthe mad pseudo-civilization that surrounded him. He was quite certain thatthe beings he had seen could not possibly be the real rulers of thissociety, but he had, as yet, no inkling as to who the real rulers were.

  As to _where_ they were, that question seemed a little easier to answer.It was highly probable that they were out in space, on the asteriods thathis instruments had detected as he had dropped in toward this planet somany years before. He had made an error back then in not landing in theBelt, but at no time since had he experienced the emotion of regret orwished he had done differently; both thoughts would have beenincomprehensible to the Nipe. He had made an error; the circumstances hadbeen checked and noted; he would not make that error again.

  What further action could be taken by a logical mind?

  None. The past was unchangeable. It existed only as a memory in his ownmind, and there was no way to change that indelible record, even had hewished to do such an insane thing.

  Surely, he thought, the real rulers must know of his existence. He hadtried, by his every action, to show that he was a reasoning, intelligent,and civilized being. Why had they taken no action?

  His hypotheses, he realized, were weak because of lack of data. He couldonly wait for more information.

  That--and continue to work.

  VII

  INTERLUDE

  Mrs. Frobisher touched the control button that depolarized the window inthe breakfast room, letting the morning sun stream in. Then she said, in alow voice, "Larry, come here."

  Larry Frobisher looked up from his morning coffee. "What is it, hon?"

  "The Stanton boys. Come look."

  Frobisher sighed. "Who are the Stanton boys, and why should I come look?"But he got up and came over to the window.

  "See--over there on the walkway toward the play area," she said.

  "I see three girls and a boy pushing a wheeled contraption," Frobishersaid. "Or do you mean that the Stanford boys are dressed up as girls?"

  "_Stanton_," she corrected him. "They just moved into the apartment on thefirst floor."

  "Who? The three girls?"

  "No, silly! The two Stanton boys and their mother. One of them is in that'wheeled contraption'. It's called a therapeutic chair."

  "Oh? So the poor kid's been hurt. What's so interesting about that, asidefrom morbid curiosity?"

  The boy pushing the chair went around a bend in the walkway, out of sight,and Frobisher went back to his coffee while his wife spoke.

  "Their names are Mart and Bart. They're twins."

  "I should think," Frobisher said, applying himself to his breakfast, "thatthe mother would get a self-powered chair for the boy instead of makingthe other boy push it."

  "The poor boy can't control the chair, dear. Something wrong with hisnervous system. I understand that he was exposed to some kind of radiationwhen he was only two years old. That's why the chair has all theinstruments built into it. Even his heartbeat has to be controlledelectronically."

  "Shame." Frobisher speared a bit of sausage. "Kind of rough on both of'em, I'd guess."

  "How do you mean?"

  "Well, I mean, like.... Well, for instance, why are they going over to theplay area? Play games, right? The one that's well has to push his brotherover there--can't just get out and go; has to take the brother along. Kindof a burden, see?

  "And then, the kid in the chair has to sit there and watch his brotherplay basketball or jai alai, while he can't do anything himself. Like Isay, kind of rough on both of them."

  "Yes, I suppose it must be. More coffee?"

  "Thanks, honey. And another slice of toast, hunh?"

  VIII

  The two objects floating in space both looked like pitted pieces of rock.The larger one, roughly pear-shaped and about a quarter of a mile in itsgreatest dimension, was actually that--a hunk of rock. The smaller--_much_smaller--of the two was a camouflaged spaceboat. The smaller was on anear-collision course with reference to the larger, although theirrelative velocities were not great.

  At precisely the right time, the smaller drifted by the larger, only a fewhundred yards away. The weakness of the gravitational fields generatedbetween the two caused only a slight change of orbit on the part of bothbodies. Then they began to separate.

  But, during the few seconds of their closest approach, a third body haddetached itself from the camouflaged spaceboat and shot rapidly across theintervening distance to land on the surface of the floating mountain.

  The third body was a man in a spacesuit. As soon as he landed, he satdown, stock-still, and checked the instrument case he held in his hands.

  No response. Thus far, then, he had succeeded.

  He had had to pick his time precisely. The people who were already on thissmall planetoid could not use their detection equipment while theplanetoid itself was within detection range of Beacon 971, only twohundred and eighty miles away. Not if they wanted to keep from beingfound. Radar pulses emanating from a presumably lifeless planetoid wouldbe a dead giveaway.

  Other than that, they were mathematically safe--if they depended on thelaws of chance. No ship moving through the Asteroid Belt would dare tomove at any decent velocity without using radar, so the people on thisparticular lump of planetary flotsam would be able to spot a ship'sapproach easily, long before their own weak detection system wouldregister on the pick-ups of the approaching ship.

  The power and range needed by a given detector depends on the relativevelocity--the greater that velocity, the more power, the greater rangeneeded. At one mile per second, a ship needs a range of only thirty milesto spot an obstacle thirty seconds away; at ten miles per second, it needsa range of three hundred miles.

  The man who called himself Stanley Martin had carefully plotted the orbitof this particular planetoid and then let his spaceboat coast in withoutusing any detection equipment except the visual. It had been necessary,but very risky.

  Had the people here seen his boat? If so, had they recognized it, in spiteof the heavy camouflage? And, even if they only suspected, what would betheir reaction?

  He waited.

  It takes nerve and patience to wait for thirteen solid hours withoutmoving more than an occasional flexure of muscles, but he managed thatlong before the instrument case waggled a meter needle at him. The onerelieving factor was the low gravity; on an asteroid, the problem ofsleeping on a bed of nails is caused by the likelihood of accidentallythrowing oneself off the bed. The probability of puncture or discomfortfrom the points is almost negligible.

  When the needle on the instrument panel flickered, he got to his feet andbegan moving. He was almost certain that he had not been detected.

  Walking was out of the question. This was a silicate-alumina rock, not anickel-iron one. The group that occupied it had deliberately chosen itthat way, so that there would be no chance of its being picked out forslicing by one of the mining teams in the Asteroid Belt. Granted, thechance of any given metallic planetoid's being selected was very small,they had not even wanted to take that chance. Therefore, without anymagnetic field to hold him down, and only a very tiny gravitic field, theman had to use different tactics.

  It was more like mountain climbing than anything else, except that therewas no danger of falling. He crawled over the surface in the same way thatan Alpine climber might crawl up the side of a steep slope--seekinghandholds and toeholds and using them to propel himself onward. The onlydifference was that he covered distance a great deal more rapidly than amountain climber could.

  When he reached the spot he wanted, he carefully concealed himself beneatha craggy overhang. It took a little searching to find exactly the rightspot, but when he did, he settled himself into place in a small pit andbegan more elab
orate preparations.

  Self-hypnosis required nearly ten minutes. The first five or six minuteswere taken up in relaxing from his exertion. Gravity notwithstanding, hehad had to push his hundred and eighty pounds of mass over a considerabledistance. When he was completely relaxed and completely hypnotized, hereached up and cut down the valve that fed oxygen into his suit.

  Then, of his own will, he went cataleptic.

  * * * * *

  A single note, sounded by the instruments in the case by his side, wokehim instantly. He came fully awake, as he had commanded himself to do.

  Immediately, he turned up his oxygen intake, at the same time glancing atthe clock dial in his helmet. He smiled. Nineteen days and seven hours. Hehad calculated it almost precisely. He wasn't more than an hour off, whichwas pretty good, all things considered.

  He consulted his instruments again. The