Calamitously, the reverse also appeared to be true. Sweeney had been unable to find anybody in the colony who believed it possible to convert an Adapted Man back into a human being.

The promise the Port cops had held out to himthough they had never made it directlythus far appeared to be founded upon nothing better than dust. If it were nevertheless possible to bring a man like Sweeney back to life, only Ruttman knew about it, and Sweeney had to be hypercautious in questioning Rullman. The scientist had already made some uncomfortable deductions from the spa.r.s.e facts and ample lies with which Sweeney had, by order of the Port cops, provided him. Like everyone else on Ganymede, Sweeney had learned to respect the determination and courage which were bodied forth in everything Rullman did and said; but unlike anybody else on Ganymede, he feared Rullman's understanding.

And in the meantimewhile Sweeney waited, with a fatal- ism disturbed only by Mike Leverault, for Rullman to see through him to the other side of the gouge which was Sween- ey's frigid tangled subst.i.tute for a human soulthere re- mained the question of the crime.

We must have those men back. Why? Because we need to know what they know. Why not ask them? They won't tell us.

Why not? Because they're afraid. What of? They committed a crime and must be punished. What did they do?

SILENCE.

So the question of the crime still remained. It had not been commerce-raiding; even had the Ganymedians achieved the impossible and had pirated s.p.a.cecraft, that would not have been the first crime, the one which had made the Adapted Men flee to Ganymede in the first place, the crime from which the whole technique of pantropy had sprung. What high crime had the parents of the Adapted Men committed, to force them to maroon their children on Ganymede for what they must have believed was to be forever?

The responsibility was not the children's, that much was also obvious. The children had never been on the Earth at all.

They had been born and raised on the Moon, in strict secre- cy. The cops' pretense that the colonists themselves were wanted back for some old ,evil was another fraud, like the story about commerce-raiding. If a crime had been com- mitted on Earth, it had been committed by the normal Earth- men whose frigid children roamed Ganymede now; it could have been committed by no-one else.

Except, of course, by Rullman. Both on the Moon and on Ganymede it was the common a.s.sumption that Rullman had been an Earth-normal human being once. That was impossible, but it was agreed to be so. Rullman himself turned the ques- tion away rather than deny it. Perhaps the crime had been his alone, since there was n.o.body else who could have com- mitted it.

But what crime? n.o.body on Ganymede could, or would, tell Sweeney. None of the colonists believed in it. Most of them thought that nothing was held against them but their difference from normal human beings; the exceptional few thought that the development of pantropy itself was the es- sential crime. Of that, clearly, Rullman was guilty, if "guilty"

was the applicable word.

Why pantropy, or the responsibility for developing it, should be considered criminal was a mystery to Sweeney, but there was a great deal else that he didn't know about Earth laws and standards, so he wasted no more time in puzzling over it. If Earth said that inventing or using paniropy was a crime, that was what it was; and the Port cops had already told him that he must not fail to brins. back Rullman, no mat- ter how grievously he failed to fulfill all his other instruc- tions. It was an answer, and that was enough.

But why hadn't the cops said so in the first place? And why, if pantropy was a crime, had the cops themselves com- pounded that identical crimeby creating Sweeney?

Belatedly, he quickened his pace. Mike had already disap- peared under the lowering brow of the great cavern. He. could not remember noticing, now, which of the dozen smaller en- trances she had used, and he himself did not know where more than two of them led. He chose one at random.

Four turns later, he was hopelessly lost.

This was unusual, but it was not entirely unexpected. The network of tunnels under Howe's pi was a labyrintb, not only in fact but by intention. In drilling out their home, the Adapted Men had taken into consideration the possibility that gun-carrying men in .s.p.a.cesuits might some day come looking for them. Such a man would never find his way out from under the mountain, unless an Adapted Man who had memorized the maze led him out; and he would never find an Adapted Man, either. MemorizatioTi was the only key, for no maps of the maze existed, and the colonists had a strictly en- forced law against drawing one.

Sweeney had perhaps half of the maze committed to mem- ory. If he did not meet someone he knewfor after all, no- body was hiding from himhe could count upon entering a familiar section sooner or later. In the meantime, he was curious to see anything that there was to be seen.

The first thing of interest that he saw was Dr. Rullman. The scientist emerged froln a tunnel set at a 20 angle to the one Sweeney was in at the moment, going away from Sweeney and unaware of him. After an instant's hesitation, Sweeney fol- lowed him, as silently as possible. The noisy ventilation sys- tem helped to cover his footfalls.

Rullman had a habit of vanishing for periods ranging from half a day to a week. Anybody who knew where he went and what he did there did not talk about it. Now was a chance, perhaps, for Sweeney to find out for himself. It was possible, of course, that Rullman's disappearances were re- lated to the forthcoming meteorological crisis on Ganymede, about which Sweeney had been hearing an increasing number of hints. On the other hand . . . what was on the other hand?

There could be no harm in investigating.

Rullman walked rapidly, his chin ducked into his chest, as though he were travelling a route so familiar that habit could be entrusted with carrying him along it. Once Sweeney al- most lost him, and thereafter cautiously closed up the interval between them a little; the labyrinth was sufficiently complex to offer plenty of quick refuges should Rullman show signs of turning back. As the scientist moved, there came from him an unpredictable but patterned series of wordless sounds, intoned rather than spoken. They communicated nothing, actuated no mechanisms, gave Rullman no safe-conductas was evi- denced by the fact that Sweeney was travelling the same course without making any such noise. Indeed, Rullman him- self seemed to be unaware that he was making it.

Sweeney was puzzled. He had never heard anybody hum before.

The rock beneath Sweeney's feet began to slope downward, gently but definitely. At the same time, he noticed that the air was markedly warmer, and was becoming more so with almost every step. A dim sound of laboring machinery was pulsing in it.

It got hotter, and still hotter, but Rullman did not hesitate.

The noisewhich Sweeney could now identify definitely as that of pumps, many of themalso increased. The two men were now walking down a long, straight corridor, bordered by closed doors rather than maze exits; it was badly lit, but Sweeney nevertheless allowed Rullman to get farther ahead of him. Toward the other end of this corridor, the heat began to diminish, to Sweeney's relief, for he had begun to feel quite dizzy. Rullman gave no indication that he even noticed it.

At this end Rullman ducked abruptly into a side entrance which turned out to be the top of a flight of stone steps.

Quite a perceptible draft of warm air was blowing down it.

Warm air, Sweeney knew, was supposed to rise in a gravita- tional field; why it should be going in the opposite direction he could not imagine, especially since there appeared to be no blowers in operation on this level. Since it was blowing toward Rullman, it would also carry any noise Sweeney made ahead of him. He tiptoed cautiously down.

Rullman was not in sight when Sweeney left the stairwell.

There was before Sweeney, instead, a long, high-ceilinged pa.s.sageway which curved gently to the right until vision was cut off. Along the inside of the curve, regularly s.p.a.ced, were crouching machines, each one with a bank of laterally-coiled metal tubing rearing before it. These were the sources of the sounds Sweeney had heard.

Here, it was cold again; abnormally cold, despite the heavy current of warm air blowing down the stab-well. Something, Sweeney thought, was radically wrong with the behaviour of the thermody-namic laws down here.

He slouched cautiously ahead. After only a few steps, past the first of the laboring mechanismsyes, it was coldest by the shining coils, as if cold were actually radiating from them he found an undeniable aJrlock. Furthermore, it was in use: the outer door was sealed, but a little light beside it said that the lock was cycling. Opposite the lock, on the other wall, one of a row of s.p.a.cesuit lockers hung open and tenantless.

But it was the legend painted on the airlock valve which finally made everything fall into place. It said: PANTROPE LABORATORY ONE.

Danger Keep Out!

Sweeney dodged away from the airlock with a flash of pure panic, as a man wanted for murder might jump upon seeing a sign saying "50,000 volts." It was all clear now. There was nothing wrong with the thermodynamics of this corridor that was not similarly "wrong" inside any refrigerator. The huge engines were pumps, all rightheat pumps. Their coils were frost-free only because there was no water vapor in Gany- mede's air; nevertheless, they were taking heat from that air and transferring it to the other side of that rock wall, into the pantrobe lab.

No wonder the laboratory was sealed off from the rest of the maze by an airlockand that RuUman had had to put on a s.p.a.cesuit to go through it.

It was hot on the other side. Too hot for an Adapted Man.

But what Adapted Man?

What good was pantropy to Rullman here? That phase of history was supposed to be over and done with. Yet what was going on in this laboratory obviously was as alien to the en- vironment of Ganymede as Ganymede's environment was to Earth's.

A is to B as Bis towhat? To C? Or to A?

Was Rullman, in the face of the impossibility of such a project, trying to re-adapt his people to Earth?

There should be dials or meters on this side of the wall which would give more information as to what it was like on the other side. And there they were, in a little hooded embra- sure which Sweeney had overlooked in the first shock. They said:

r 59 Degrees F.

Millibars

047 0140.

Dew Point 02 Tens rnrn Hg Some of these meant nothing to Sweeney: he had never before encountered pressure expressed in millibars, let alone the shorthand way it was registered on the meter before him; nor did he know how to compute relative humidity from the dew point. With the Fahrenheit scale he was vaguely familiar, vaguely enough to have forgotten how to convert it into Centigrade readings. But Oxygen tension!

There was one planet, and one only, where such a measure- ment could have any meaning.

Sweeney ran.

He was no longer running by the time he had reached Rull- man's office, although he was still thoroughly out of breath.

Knowing that he would be unable to cross back over the top of the pantrobe lab again, feeling that heat beating up at him and knowing at least in part what it meant, he had gone in the opposite direction, past the gigantic heat-exchangers, and blundered his way up from the other side. The route he had followed had covered over three erratic miles, and several ad- ditional discoveries which bad shaken him almost as hard as had the first one.

He was entirely unsure that he was even rational any more.

But he had to know. Nothing was important to him now but the answer to the main question, the permanent founding or dashing of the hope under which he had lived so long.

RuUman was already back in the office, almost surrounded by his staff. Sweeney pushed his way forward among the Ganymedians, his jaw set, his diaphragm laboring.

"This time we're going to close all the safety doors," Rull- man said into the phone. "The pressure fronts are going to be too steep to allow us to rely on the outside locks alone. See to it that everybody knows where he's to be as soon as the alert sounds, and this time make it stick; we don't want anybody trapped between doors for the duration. This time it may swoop down on us at d.a.m.n short notice."

The phone murmured and cut out.

"Hallam, how's the harvesting? You've got less than a week, you know."

"Yes, Dr. Rullmanwe'll be through in time."

"And another thingoh, h.e.l.lo, Donald. What's the mat- ter? You're looking a little pasty. I'm pretty busy, so make it fast, please."

"I'll make it fast," Sweeney said. "I can put it all into one question if I can talk to you privately. For just a few sec- onds,"

Rullman's reddish eyebrows went up, but after examining Sweeney's face more closely, the scientist nodded and rose.

"Come next door, then. . . . Now then, youngster, spit it out.

With the storm coming up, we don't have time for shilly- shallying."

"All right," Sweeney said, taking a long breath. "This is it: Is it possible to change an Adapted Man back into a human being? An Earth-normal human being?"

Rullman's eyes narrowed very slowly; and for what seemed a long time, he said nothing. Sweeney looked back. He was afraid, but he was -no longer afraid of Rullman.

"You've been down below, I see," the scientist said at last, drumming at the base of his chin with two fingers. "And from the terms you use, it strikes me that Shirley Leverault's edu- cational methods leftwell, the cliche springs to mind something to be desired. But we'll let those things pa.s.s for now.

"The answer to your question, in any case, is: No. You will never be able to live a normal life in any other place than Ganymede, Donald. And 111 tell you something else that your mother should have told you: You ought to be d.a.m.ned glad of it."

"Why should I?" Sweeney said, almost emotionlessly.

"Because, like every other person in this colony, you have a Jay-positive blood type. This wasn't concealed from you when we found it, on the first day you joined us, but evidently it didn't registeror had no special significance for you. Jay- positive blood doesn't mean anything on Ganymede, true enough. But Jay-positive Earth-normal people are cancer- p.r.o.nes. They are as susceptible to cancer as hemophiliacs are to bleeding to deathand upon equally short notice.

"If by some miracle you should be changed to an Earth- normal man, Donald, you would be under immediate sentence of death. So I say you should be glad that it can't happen d.a.m.n glad I"

3.

The crisis on Ganymedethough of course it would not even be an incident, were there n.o.body there to live through it comes to fruition roughly every eleven years and nine months.

It is at the end of this period that Jupiterand hence his fif- teen-fold family of moons and moonletsmakes his closest approach to the Sun.

The eccentricity of Jupiter's...o...b..t is only 0.0484, which amounts to very little for an ellipse which averages 483,300,- 000 miles from its focal points. Nevertheless, at perihelion Jupiter is nearly ten million miles closer to the Sun than he is at aphelion; and the weather on Jupiter, never anything less than h.e.l.lish, becomes indescribable during that approach. So, on a smaller but sufficient scale, does the weather on Gany- mede.

The perihelion temperature on Ganymede never rises high enough to melt the ice of Neptune's Trident, but it does lift through the few n.i.g.g.ardly degrees necessary to make the vapor pressure of Ice III known in Ganymede's air. n.o.body on Earth could dream of calling the resulting condition "hu- midity," but Ganymede's weather turns upon such microscopic changes; an atmosphere containing no water will react rapidly to even a fractional vapor content. For one thing, it will pick up more heat. The resulting cycle does not go through more than a few turns before it flattens out, but the end-product is no less vicious.

The colony, Sweeney gathered, had come through one such period without any but minor difficulties, simply by withdraw- ing entirely under the mountain; but for many reasons that course was no longer possible. There were now semi-perma- nent installationsweather stations, observatories, radio bea- cons, bench-marks and other surveying monumentswhich could be dismantled only with the loss of much time before the crisis, and re-established with still more loss afterwards.

Furthermore, some of them would be needed to report and record the progress of the crisis itself, and hence had to stay where they were.

"And don't get the idea," Rullman told a ma.s.s meeting of the colonists, gathered, in the biggest cavern of the maze, "that even the mountain can protect us all the way through this one. I've told you before, but I'll remind you again, that the climax this year coincides with the peak of the sunspot cycle. Everybody's seen what that does to the weather on Ju- piter proper. We can expect similar effects, to scale, on Gany- mede. There's going to be trouble no matter how well we pre- pare. All we can hope for is that the inevitable damage will be minor. Anybody who thinks we're going to get off scot-free has only to listen for a minute."

In the calculated, dramatic pause which followed, every- body listened. The wind was audible even down here, howl- ing over the outlets and intakes of the ventilation system, car- ried, amplified and encrusted with innumerable echoes, by the metal miles of the air ducts. The noise was a reminder that, at the height of the coming storm, the exterior ports would all be closed, so that everyone under the mountain would have to breathe recirculated air. After a moment, a ma.s.s sighan involuntary intake of breath against 'the easily imagined futurepa.s.sed through RuUman's audience. He grinned.

"I don't mean to frighten you," he said. "We'll get along.

But I don't want any complacency either, and above all, I won't stand for any sloppiness in the preparations. It's parti- cularly important that we keep the outside installations intact this time, because we're going to need them before the end of .the next Jovian yeara long time before that, if everything continues to go well."

The grin was suddenly quenched. "I don't need to tell some of you how important it is that we get that project completed on schedule," Rullman said, quietly. "We may not have much time left before the Port cops decide to move in on usit amazes me that they haven't already done so, particularly since we're harboring a fugitive the cops troubled to chase almost into our atmosphereand we can't plan on their giv- ing us any leeway.

"For those of you who know about the project only in out- line, let me emphasize that there is a good deal more hanging from it than immediately meets the eye. Man's whole future in s.p.a.ce may be determined by how well we carry it off; we can't afford to be lickedneither by the Earth nor by the weather. If we are, our whole long struggle for survival will have been meaningless. I'm counting on everyone here to see to it that that doesn't happen."

It was difficult to be sure of what Rullman was talking about when he got onto the subject of the "project." It had something to do with the pantrope labs, that much was clear; and it bad to do also with the colony's original s.p.a.ceship, which Sweeney had run across that same day, stored in a launching chimney almost identical with the one on the Moon out of which Sweeney had been rocketed to begin his own free life, and fittedif judgment based upon a single brief look could be trustedeither for a long voyage by a few people, or for a short trip by a large group.

Beyond that, Sweeney knew nothing about the "project,"

except for one additional fact of which he could make noth- ing: it had something to do with the colony's long-term ar- rangements for circ.u.mventing the loss of unfixed penes. Pos- sibly-n.o.body would be less abTe to a.s.sess the possibility than Sweeneythe only connection this fact had with the "pro- ject" was that it was long-term.

Sweeney, in any event, knew better than to ask questions.

The storm that was going on inside him took precedence, anyhow; as far as he was concerned, it was even more im- portant than the storms that were sweeping Ganymede, or any that might sweep that world in the foreseeable future. He was not used to thinking in terms of a society, even a small one; Pullman's appeals to that Ideal were simply incomprehensible to him He was the solar system's most thorough-going indi- vidualistnot bynature, but by design.

Perhaps Rullman sensed it. Whether he did or not, the as- signment he gave Sweeney might have been perfectly calcu- lated to throw a lonely man into the ultimate isolation he feared; to put the burden of an agonizing decision entirely upon the shoulders of the man who had to carry it; orto isolate a Port spy where he could do the least harm while the colony's attention was fully occupied elsewhere. Or possibly, even probably, he had none of these motives in mind; what counted, in any event, was what he did.

He a.s.signed Sweeney to the South polar weather station, for the duration of the emergency.'

There was almost nothing to do there but watch the crys- tals of methane "snow" bank against the windows, and keep the station tight. The' instruments reported back to base by themselves, and needed no further attention. At the height of the crisis, perhaps, Sweeney might find himself busy for a while; or, he might not. That remained to be seen.

In the meantime, he had plenty of time to ask questions and n.o.body to ask them of but himself, and the hooting, con- stantly rising wind.

There was an interlude. Sweeney hiked, on foot, back to Howe's H to recover the radio transceiver he had buried there, and then hiked back to the weather station. It took him eleven days, and efforts and privations of which Jack London might have made a whole novel. To Sweeney it meant nothing; he did not know whether or not he would want to use the radio after he got back with it; and as for the saga of his solo jour- ney, he did not know that it was a saga, or even that it had been unusually difficult and painful. He had nothing against which to compare it, not even fiction; he had never read any.

He measured things by the changes they made in his situation, and possession of the radio had not changed the questions he was asking himself; it had only made it possible to act upon the answers, once he had any answers.