* * *

  He looked around, blinking. After the Jovian surface, it was always a little unreal to find himself here again, in the clean, quiet orderliness of the control room.

  His muscles ached. They shouldn’t. He had not really been fighting a gale of several hundred miles an hour, under three gravities and a temperature of 140 absolute. He had been here, in the almost nonexistent pull of Jupiter V, breathing oxynitrogen. It was Joe who lived down there and filled his lungs with hydrogen and helium at a pressure which could still only be estimated, because it broke aneroids and deranged piezoelectrics.

  Nevertheless, his body felt worn and beaten. Tension, no doubt—psychosomatics. After all, for a good many hours now he had, in a sense, been Joe, and Joe had been working hard.

  With the helmet off, Anglesey held only a thread of identification. The esprojector was still tuned to Joe’s brain but no longer focused on his own. Somewhere in the back of his mind, he knew an indescribable feeling of sleep. Now and then, vague forms or colors drifted in the soft black—dreams? Not impossible that Joe’s brain should dream a little when Anglesey’s mind wasn’t using it.

  A light flickered red on the esprojector panel, and a bell whined electronic fear. Anglesey cursed. Thin fingers danced over the controls of his chair, he slewed around and shot across to the bank of dials. Yes, there—K tube oscillating again! The circuit blew out. He wrenched the face plate off with one hand and fumbled in a drawer with the other.

  Inside his mind, he could feel the contact with Joe fading. If he once lost it entirely, he wasn’t sure he could regain it. And Joe was an investment of several million dollars and quite a few highly skilled man-years.

  Anglesey pulled the offending K tube from its socket and threw it on the floor. Glass exploded. It eased his temper a bit, just enough so he could find a replacement, plug it in, switch on the current again. As the machine warmed up, once again amplifying, the Joeness in the back alleys of his brain strengthened.

  Slowly, then, the man in the electric wheel chair rolled out of the room, into the hall. Let somebody else sweep up the broken tube. To hell with it. To hell with everybody.

  * * *

  Jan Cornelius had never been farther from Earth than some comfortable Lunar resort. He felt much put upon that the Psionics Corporation should tap him for a thirteen-month exile. The fact that he knew as much about esprojectors and their cranky innards as any other man alive was no excuse. Why send anyone at all? Who cared?

  Obviously the Federation Science Authority did. It had seemingly given those bearded hermits a blank check on the taxpayer’s account.

  Thus did Cornelius grumble to himself, all the long hyperbolic path to Jupiter. Then the shifting accelerations of approach to its tiny inner satellite left him too wretched for further complaint. And when he finally, just prior to disembarkation, went up to the greenhouse for a look at Jupiter, he said not a word. Nobody does, the first time.

  Arne Viken waited patiently while Cornelius stared. It still gets me too, he remembered. By the throat. Sometimes I’m afraid to look.

  At length Cornelius turned around. He had a faintly Jovian appearance himself, being a large man with an imposing girth. “I had no idea,” he whispered. “I never thought…I had seen pictures, but…”

  Viken nodded. “Sure, Dr. Cornelius. Pictures don’t convey it.”

  Where they stood, they could see the dark broken rock of the satellite, jumbled for a short way beyond the landing slip and then chopped off sheer. This moon was scarcely even a platform, it seemed, and cold constellations went streaming past it, around it. Jupiter lay across a fifth of that sky, softly ambrous, banded with colors, spotted with the shadows of planet-sized moons and with whirlwinds as broad as Earth. If there had been any gravity to speak of, Cornelius would have thought, instinctively, that the great planet was falling on him. As it was, he felt as if sucked upward, his hands were still sore where he had grabbed a rail to hold on.

  “You live here…all alone…with this?” He spoke feebly.

  “Oh, well, there are some fifty of us all told, pretty congenial,” said Viken. “It’s not so bad. You sign up for four-cycle hitches—four ship arrivals—and believe it or not, Dr. Cornelius, this is my third enlistment.”

  The newcomer forbore to inquire more deeply. There was something not quite understandable about the men on Jupiter V. They were mostly bearded, though otherwise careful to remain neat; their low-gravity movements were somehow dreamlike to watch; they hoarded their conversation, as if to stretch it through the year and a month between ships. Their monkish existence had changed them—or did they take what amounted to vows of poverty, chastity, and obedience because they had never felt quite at home on green Earth?

  Thirteen months! Cornelius shuddered. It was going to be a long, cold wait, and the pay and bonuses accumulating for him were scant comfort now, four hundred and eighty million miles from the sun.

  “Wonderful place to do research,” continued Viken. “All the facilities, hand-picked colleagues, no distractions—and, of course…” He jerked his thumb at the planet and turned to leave.

  Cornelius followed, wallowing awkwardly. “It is very interesting, no doubt,” he puffed. “Fascinating. But really, Dr. Viken, to drag me way out here and make me spend a year-plus waiting for the next ship—to do a job which may take me a few weeks…”

  “Are you sure it’s that simple?” asked Viken gently. His face swiveled around, and there was something in his eyes that silenced Cornelius. “After all my time here, I’ve yet to see any problem, however complicated, which when you looked at it the right way didn’t become still more complicated.”

  * * *

  They went through the ship’s air lock and the tube joining it to the station entrance. Nearly everything was underground. Rooms, laboratories, even halls, had a degree of luxuriousness—why, there was a fireplace with a real fire in the common room! God alone knew what that cost! Thinking of the huge chill emptiness where the king planet laired, and of his own year’s sentence, Cornelius decided that such luxuries were, in truth, biological necessities.

  Viken showed him to a pleasantly furnished chamber which would be his own. “We’ll fetch your luggage soon, and unload your psionic stuff. Right now, everybody’s either talking to the ship’s crew or reading his mail.”

  Cornelius nodded absently and sat down. The chair, like all low-gee furniture, was a mere spidery skeleton, but it held his bulk comfortably enough. He felt in his tunic, hoping to bribe the other man into keeping him company for a while. “Cigar? I brought some from Amsterdam.”

  “Thanks.” Viken accepted with disappointing casualness, crossed long, thin legs and blew grayish clouds.

  “Ah…are you in charge here?”

  “Not exactly. No one is. We do have one administrator, the cook, to handle what little work of that type may come up. Don’t forget, this is a research station, first, last, and always.”

  “What is your field, then?”

  Viken frowned. “Don’t question anyone else so bluntly, Dr. Cornelius,” he warned. “They’d rather spin the gossip out as long as possible with each newcomer. It’s a rare treat to have someone whose every last conceivable reaction hasn’t been—no, no apologies to me. ’S all right. I’m a physicist, specializing in the solid state at ultra-high pressures.” He nodded at the wall. “Plenty of it to be observed—there!”

  “I see.” Cornelius smoked quietly for a while. Then: “I’m supposed to be the psionics expert, but, frankly, at present I’ve no idea why your machine should misbehave as reported.”

  “You mean those, uh, K tubes have a stable output on Earth?”

  “And on Luna, Mars, Venus—everywhere, apparently, but here.” Cornelius shrugged. “Of course, psibeams are always persnickety, and sometimes you get an unwanted feedback when—no. I’ll get the facts before I theorize. Who are your psimen?”

  “Just Anglesey, who’s not a formally trained esman at all. But he took it up after he was crippled, and showed such a natural aptitude that he was shipped out here when he volunteered. It’s so hard to get anyone for Jupiter V that we aren’t fussy about degrees. At that, Ed seems to be operating Joe as well as a Ps.D. could.”

  “Ah, yes. Your pseudojovian. I’ll have to examine that angle pretty carefully, too,” said Cornelius. In spite of himself, he was getting interested. “Maybe the trouble comes from something in Joe’s biochemistry. Who knows? I’ll let you into a carefully guarded little secret, Dr. Viken: psionics is not an exact science.”

  “Neither is physics,” grinned the other man. After a moment, he added more soberly: “Not my brand of physics, anyway. I hope to make it exact. That’s why I’m here, you know. It’s the reason we’re all here.”

  * * *

  Edward Anglesey was a bit of a shock the first time. He was a head, a pair of arms, and a disconcertingly intense blue stare. The rest of him was mere detail, enclosed in a wheeled machine.

  “Biophysicist originally,” Viken had told Cornelius. “Studying atmospheric spores at Earth Station when he was still a young man—accident, crushed him up, nothing below his chest will ever work again. Snappish type, you have to go slow with him.”

  Seated on a wisp of stool in the esprojector control room, Cornelius realized that Viken had been soft-pedaling the truth.

  Anglesey ate as he talked, gracelessly, letting the chair’s tentacles wipe up after him. “Got to,” he explained. “This stupid place is officially on Earth time, GMT. Jupiter isn’t. I’ve got to be here whenever Joe wakes, ready to take him over.”

  “Couldn’t you have someone spell you?” asked Cornelius.

  “Bah!” Anglesey stabbed a piece of prot and waggled it at the other man. Since it was native to him, he could spit out English, the common language of the station, with unmeasured ferocity. ‘‘Look here. You ever done therapeutic esping? Not just listening in, or even communication, but actual pedagogic control?”

  “No, not I. It requires a certain natural talent, like yours.” Cornelius smiled. His ingratiating little phrase was swallowed without being noticed by the scored face opposite him. “I take it you mean cases like, oh, re-educating the nervous system of a palsied child?”

  “Yes, yes. Good enough example. Has anyone ever tried to suppress the child’s personality, take him over in the most literal sense?”

  “Good God, no!”

  “Even as a scientific experiment?” Anglesey grinned. “Has any esprojector operative ever poured on the juice and swamped the child’s brain with his own thoughts? Come on, Cornelius, I won’t snitch on you.”

  “Well…it’s out of my line, you understand.” The psionicist looked carefully away, found a bland meter face and screwed his eyes to that. “I have, uh, heard something about…Well, yes, there were attempts made in some pathological cases to, uh, bull through…break down the patient’s delusions by sheer force—”

  “And it didn’t work,” said Anglesey. He laughed. “It can’t work, not even on a child, let alone an adult with a fully developed personality. Why, it took a decade of refinement, didn’t it, before the machine was debugged to the point where a psychiatrist could even ‘listen in’ without the normal variation between his pattern of thought and the patient’s—without that variation setting up an interference scrambling the very thing he wanted to study. The machine has to make automatic compensations for the differences between individuals. We still can’t bridge the differences between species.

  “If someone else is willing to cooperate, you can very gently guide his thinking. And that’s all. If you try to seize control of another brain, a brain with its own background of experience, its own ego, you risk your very sanity. The other brain will fight back instinctively. A fully developed, matured, hardened human personality is just too complex for outside control. It has too many resources, too much hell the subconscious can call to its defense if its integrity is threatened. Blazes, man, we can’t even master our own minds, let alone anyone else’s!”

  Anglesey’s cracked-voice tirade broke off. He sat brooding at the instrument panel, tapping the console of his mechanical mother.

  “Well?” said Cornelius after a while.

  He should not, perhaps, have spoken. But he found it hard to remain mute. There was too much silence—half a billion miles of it, from here to the sun. If you closed your mouth five minutes at a time, the silence began creeping in like fog.

  “Well,” gibed Anglesey. “So our pseudojovian, Joe, has a physically adult brain. The only reason I can control him is that his brain has never been given a chance to develop its own ego. I am Joe. From the moment he was ‘born’ into consciousness, I have been there. The psibeam sends me all his sense data and sends him back my motor-nerve impulses. Nevertheless, he has that excellent brain, and its cells are recording every trace of experience, even as yours and mine; his synapses have assumed the topography which is my ‘personality pattern.’

  “Anyone else, taking him over from me, would find it was like an attempt to oust me myself from my own brain. It couldn’t be done. To be sure, he doubtless has only a rudimentary set of Anglesey-memories—I do not, for instance, repeat trigonometric theorems while controlling him—but he has enough to be, potentially, a distinct personality.

  “As a matter of fact, whenever he wakes up from sleep—there’s usually a lag of a few minutes, while I sense the change through my normal psi faculties and get the amplifying helmet adjusted—I have a bit of a struggle. I feel almost a…a resistance until I’ve brought his mental currents completely into phase with mine. Merely dreaming has been enough of a different experience to…” Anglesey didn’t bother to finish the sentence.

  “I see,” murmured Cornelius. “Yes, it’s clear enough. In fact, it’s astonishing that you can have such total contact with a being of such alien metabolism.”

  “I won’t for much longer,” said the esman sarcastically, “unless you can correct whatever is burning out those K tubes. I don’t have an unlimited supply of spares.”

  “I have some working hypotheses,” said Cornelius, “but there’s so little known about psibeam transmission—is the velocity infinite or merely very great, is the beam strength actually independent of distance? How about the possible effects of transmission—oh, through the degenerate matter in the Jovian core? Good Lord, a planet where water is a heavy mineral and hydrogen is a metal! What do we know?”

  “We’re supposed to find out,” snapped Anglesey. “That’s what this whole project is for. Knowledge. Bull!” Almost, he spat on the floor. “Apparently what little we have learned doesn’t even get through to people. Hydrogen is still a gas where Joe lives. He’d have to dig down a few miles to reach the solid phase. And I’m expected to make a scientific analysis of Jovian conditions!”

  Cornelius waited it out, letting Anglesey storm on while he himself turned over the problem of K-tube oscillation.

  “They don’t understand back on Earth. Even here they don’t. Sometimes I think they refuse to understand. Joe’s down there without much more than his bare hands. He, I, we started with no more knowledge than that he could probably eat the local life. He has to spend nearly all his time hunting for food. It’s a miracle he’s come as far as he has in these few weeks—made a shelter, grown familiar with the immediate region, begun on metallurgy, hydrurgy, whatever you want to call it. What more do they want me to do, for crying in the beer?”

  “Yes, yes,” mumbled Cornelius. “Yes, I…”

  Anglesey raised his white bony face. Something filmed over in his eyes.

  “What—” began Cornelius.

  “Shut up!” Anglesey whipped the chair around, groped for the helmet, slapped it down over his skull. “Joe’s waking. Get out of here.”

  “But if you’ll let me work only while he sleeps, how can I—”

  Anglesey snarled and threw a wrench at him. It was a feeble toss, even in low gee. Cornelius backed toward the door. Anglesey was tuning in the esprojector. Suddenly he jerked.

  “Cornelius!”

  “Whatisit?” The psionicist tried to run back, overdid it, and skidded in a heap to end up against the panel.

  “K tube again.” Anglesey yanked off the helmet. It must have hurt like blazes, having a mental squeal build up uncontrolled and amplified in your own brain, but he said merely: “Change it for me. Fast. And then get out and leave me alone. Joe didn’t wake up of himself. Something crawled into the dugout with me—I’m in trouble down there!”

  * * *

  It had been a hard day’s work, and Joe slept heavily. He did not wake until the hands closed on his throat.

  For a moment then he knew only a crazy smothering wave of panic. He thought he was back on Earth Station, floating in null gee at the end of a cable while a thousand frosty stars haloed the planet before him. He thought the great I-beam had broken from its moorings and started toward him, slowly, but with all the inertia of its cold tons, spinning and shimmering in the Earthlight, and the only sound himself screaming and screaming in his helmet, trying to break from the cable, the beam nudged him ever so gently but it kept on moving. He moved with it; he was crushed against the station wall; nuzzled into it, his mangled suit frothed as it tried to seal its wounded self. There was blood mingled with the foam—his blood. Joe roared.

  His convulsive reaction tore the hands off his neck and sent a black shape spinning across the dugout. It struck the wall, thunderously, and the lamp fell to the floor and went out.

  Joe stood in darkness, breathing hard, aware in a vague fashion that the wind had died from a shriek to a low snarling while he slept.

  The thing he had tossed away mumbled in pain and crawled along the wall. Joe felt through lightlessness after his club.

  Something else scrabbled. The tunnel! They were coming through the tunnel! Joe groped blind to meet them. His heart drummed thickly and his nose drank an alien stench.