He didn't answer. The abnormal voluntary dilation of pupils hurt his eyes.

"What else has Dr. Tighe done?" Her tone was chill in the dark. "You can't study the human mind without studying the body too. What's he done? Are you the mutant they're always speculating about? Did Dr. Tighe create or find homo superior?"

"If I don't plug that radio com-set before they can use it," he said, "I'll be homo-genized."

"You can't laugh it off," she said through taut lips. "If you aren't of our species I have to assume you're our enemy—till you prove otherwise!" Her fingers closed hard on his arm. "Is that what your little gang at the Institute is doing? Have they decided that mere humanity isn't good enough to be civilized? Are they preparing the way for your kind to take over?"

"Listen," he said wearily. "Right now we're two people, very mortal indeed, being hunted. So shut up!"

He took the pistol from her holster and slipped a full clip into its magazine. His vision was at high sensitivity now, her face showed white against the wet rock with gray highlights along its strong cheekbones beneath the wide frightened eyes. Beyond the reefs the sea was gunmetal under the stars, streaked with foam and shadow.

Ahead of him, as he rose to his feet, the line of guards stood out as paler darknesses against the vertiginous island face. They had mounted a heavy machine-gun to point seaward and a self-powered spotlight, not turned on, rested nearby. Those two things could be dangerous but first he had to find the radio set that could call the whole garrison down on them.

There! It was a small hump on the back of one man, near the middle of the beach. He was pacing restlessly up and down with a tommy-gun in his hands. Dalgetty raised the pistol with slow hard-held concentration, wishing it were a rifle. Remember your target practice now, arm loose, fingers extended, don't pull the trigger but squeeze—because you've got to be right the first time!

He shot. The weapon was a military model, semi-noiseless and with no betraying streak of light. The first bullet spun the goon on his heels and sent him lurching across sand and rock. Dalgetty worked the trigger, spraying around his victim, a storm of lead that must ruin the sender.

Chaos on the beach! If that spotlight went on with his eyes at their present sensitivity, he'd be blind for hours. He fired carefully, smashing lens and bulb. The machine-gun opened up, stuttering, wildly into the dark. If someone elsewhere on the island heard that noise—Dalgetty shot again, dropping the gunner over his weapon.

Bullets spanged around him, probing the darkness. One down, two down, three down. A fourth was running along the upward path. Dalgetty fired and missed, fired and missed, fired and missed. He was getting out of range, carrying the alarm—there! He fell slowly, like a jointed doll, rolling down the trail. The two others were dashing for the shelter of a cave, offering no chance to nail them.

Dalgetty scrambled over the rock, splashed into the bay and struck out for the shore. Shots raked the water. He wondered if they could hear his approach through the sea-noise. Soon he'd be close enough for normal night vision. He gave himself wholly to swimming.

His feet touched sand and he waded ashore, the water dragging at him. Crouching, he answered the shots coming from the cave. The shriek and yowl were everywhere around him now. It seemed impossible that they should not hear up above. He tensed his jaws and crawled toward the machine-gun. A cold part of him noticed that the fire was in a random pattern. They couldn't see him then.

The man lying by the gun was still alive but unconscious. That was enough. Dalgetty crouched over the trigger. He had never handled a weapon like this but it must be ready for action—only minutes ago it had tried to kill him. He sighted on the cave mouth and cut loose.

Recoil made the gun dance till he caught onto the trick of using it. He couldn't see anyone in the cave but he could bounce lead off its walls. He shot for a full minute before stopping. Then he crawled away at an angle till he reached the cliff. Sliding along this he approached the entrance and waited. No sound came from inside.

He risked a quick glance. Yes, it had done the job. He felt a little sick.

Elena was climbing out of the water when he returned. There was a strangeness in the look she gave him. "All taken care of?" she asked tonelessly.

He nodded, remembered she could hardly see the movement, said aloud, "Yes, I think so. Grab some of this hardware and let's get moving."

With his nerves already keyed for night vision it was not difficult to heighten other perceptions and catch her thinking ... not human. Why should he mind if he kills human beings when he isn't one himself?

"But I do mind," he said gently. "I've never killed a man before and I don't like it."

She jerked away from him. It had been a mistake, he realized. "Come on," he said. "Here's your pistol. Better take a tommy-gun too if you can handle it."

"Yes," she said. He had lowered his reception again, her voice fell quiet and hard. "Yes, I can use one."

On whom? he wondered. He picked up an automatic rifle from one of the sprawled figures. "Let's go," he said. Turning, he led the way up the path. His spine prickled with the thought of her at his back, keyed to a pitch of near-hysteria.

"We're out to rescue Michael Tighe, remember," he whispered over his shoulder. "I've had no military experience and I doubt that you've ever done anything like this either, so we'll probably make every mistake in the books. But we've got to get Dr. Tighe."

She didn't answer.

At the top of the path Dalgetty went down on his stomach again and slithered up over the crest. Slowly he raised his head to peer in front of him. Nothing moved, nothing stirred. He stooped low as he walked forward.

The thickets fenced off vision a few yards ahead. Beyond them, at the end of the slope, he could glimpse lights. Bancroft's place must be one glare of radiance. How to get in there without being seen? He drew Elena close to him. For a moment she stiffened at his touch, then she yielded. "Any ideas?" he asked.

"No," she replied.

"I could play dead," he began tentatively. "You could claim to have been caught by me, to have gotten your gun back and killed me. They might lose suspicion then and carry me inside."

"You think you could fake that?" She pulled away from him again.

"Sure. Make a small cut and force it to bleed enough to look like a bullet wound—which doesn't usually bleed much, anyway. Slow down heartbeat and respiration till their ordinary senses couldn't detect them. Near-total muscular relaxation, including even those unromantic aspects of death which are so rarely mentioned. Oh yes."

"Now I know you aren't human," she said. There was a shudder in her voice. "Are you a synthetic thing? Did they make you in the laboratory, Dalgetty?"

"I just want your opinion of the idea," he muttered with a flicker of anger.

It must have taken an effort for Elena to wrench clear of her fear of him. But then she shook her head. "Too risky. If I were one of those fellows, with all you've already done to make me wonder about you, the first thing I'd do on finding your supposed corpse would be to put a bullet through its brain—and maybe a stake through its heart. Or can you survive that too?"

"No," he admitted. "All right, it was just a thought. Let's work a bit closer to the house."

They went through brush and grass. It seemed to him that an army would make less noise. Once his straining ears caught a sound of boots and he yanked Elena into the gloom under a palmetto. Two guards tramped by, circling the land on patrol. Their forms loomed huge and black against the stars.

Near the edge of the grounds Dalgetty and Elena crouched in the long stiff grass and looked at the place they must enter. The man had had to lower his visual sensitivity as they approached the light. There were floodlights harsh on dock, airfield, barracks and lawn, with parties of guards moving around each section. Light showed in only one window of the house, on the second story. Bancroft must be there, pacing and peering out into the night where his enemy stirred. Had he called by radio for reinforcements?

At least no airboat had arrived or left. Dalgetty knew he would have seen one in the sky. Dr. Tighe was here yet—if he lived.

Decision grew in the man. There was a wild chance. "Are you much of an actress, Elena?" he whispered.

"After two years as a spy I'd better be." Her face bore a hint of puzzlement under the tension as she looked at him. He could guess her thought—For a superman, he asks some simple-minded questions. But then what is he? Or is he only dissembling?

He explained his idea. She scowled. "I know it's crazy," he told her, "but have you anything better to offer?"

"No. If you can handle your part...."

"And you yours." He gave her a bleak look, but there was an appeal in it. Suddenly his half-glimpsed face looked strangely young and helpless. "I'll be putting my life in your hands. If you don't trust me you can shoot. But you'll be killing a lot more than me."

"Tell me what you are," she said. "How can I know what the ends of the Institute are when they're using such means as you? Mutant or android or"—she caught her breath—"or actually a creature from outer space, the stars. Simon Dalgetty, what are you?"

"If I answered that," he said with desolation in his voice, "I'd probably be lying anyway. You've got to trust me this far."

She sighed. "All right." He didn't know if she was lying too.

He laid the rifle down and folded his hands on top of his head. She walked behind him, down the slope toward the light, her submachine-gun at his back.

As he walked he was building up a strength and speed no human ought to possess.

One of the sentries pacing through the garden came to a halt. His rifle swung up, and the voice was a hysterical yammer: "Who goes?"

"It's me, Buck," cried Elena. "Don't get trigger-happy. I'm bringing in the prisoner."

"Huh?"

Dalgetty shuffled into the light and stood slumped, letting his jaw hang slack as if he were near falling with weariness.

"You got him!" The goon sprang forward.

"Don't holler," said Elena. "I got this one, all right, but there are others. You keep on your beat. I got his weapons from him. He's harmless now. Is Mr. Bancroft in the house?"

"Yeah, yeah—sure." The heavy face peered at Dalgetty with more than a tinge of fear. "But lemme go along. Yuh know what he done last time."

"Stay on your post!" she snapped. "You've got your orders. I can handle him."

VIII

It might not have worked on most men but these goons were not very bright. The guard nodded, gulped and resumed his pacing. Dalgetty walked on up the path toward the house.

A man at the door lifted his rifle. "Halt, there! I'll have to call Mr. Bancroft first." The sentry went inside and thumbed an intercom switch.

Dalgetty, poised in a nervous tautness that could explode into physical strength, felt a clutch of fear. The whole thing was so fiendishly uncertain—anything could happen.

Bancroft's voice drifted out. "That you, Elena? Good work, girl! How'd you do it?" The warmth in his tone, under the excitement, made Dalgetty wonder briefly just what the relationship between those two had been.

"I'll tell you upstairs, Tom," she answered. "This is too big for anyone else to hear. But keep the patrols going. There are more like this creature around the island."

Dalgetty could imagine the primitive shudder in Thomas Bancroft, instinct from ages when the night was prowling terror about a tiny circle of fire. "All right. If you're sure he won't—"

"I've got him well covered."

"I'll send over half a dozen guards just the same. Hold it."

The men came running from barracks, where they must have been waiting for a call to arms, and closed in. It was a ring of tight faces and wary eyes and pointing guns. They feared him and the fear made them deadly. Elena's countenance was wholly blank.

"Let's go," she said.

A man walked some feet ahead of the prisoner, casting glances behind him all the time. There was one on either side, the rest were at the rear. Elena walked among them, her weapon never wavering from his back. They went down the long handsome corridor and stood on the purring escalator. Dalgetty's eyes roved with a yearning in them—how much longer, he wondered, would he be able to see anything at all?

The door to Bancroft's study was ajar and Tighe's voice drifted out. It was a quiet drawl, unshaken despite the blow it must have been to hear of Dalgetty's recapture. Apparently he was continuing a conversation begun earlier:

"... science goes back a long way, actually. Francis Bacon speculated about a genuine science of man. Poole did some work along those lines as well as inventing the symbolic logic which was to be such a major tool in solving the problem.

"In the last century a number of lines of attack were developed. There was already the psychology of Freud and his successors, of course, which gave the first real notion of human semantics. There were the biological, chemical and physical approaches to man as a mechanism. Comparative historians like Spengler, Pareto and Toynbee realized that history did not merely happen but had some kind of pattern.

"Cybernetics developed such concepts as homeostasis and feedback, concepts which were applicable to individual man and to society as a whole. Games theory, the principle of least effort and Haeml's generalized epistemology pointed toward basic laws and the analytical approach.

"The new symbologies in logic and mathematics suggested formulations—for the problem was no longer one of gathering data so much as of finding a rigorous symbolism to handle them and indicate new data. A great deal of the Institute's work has lain simply in collecting and synthesizing all these earlier findings."

Dalgetty felt a rush of admiration. Trapped and helpless among enemies made ruthless by ambition and fear, Michael Tighe could still play with them. He must have been stalling for hours, staving off drugs and torture by revealing first one thing and then another—but subtly, so that his captors probably didn't realize he was only telling them what they could find in any library.

* * * * *

The party entered a large room, furnished with wealth and taste, lined with bookshelves. Dalgetty noticed an intricate Chinese chess set on the desk. So Bancroft or Meade played chess—that was something they had in common, at least, on this night of murder.

Tighe looked up from the armchair. A couple of guards stood behind him, their arms folded, but he ignored them. "Hello, son," he murmured. There was pain in his eyes. "Are you all right?"

Dalgetty nodded mutely. There was no way to signal the Englishman, no way to let him hope.

Bancroft stepped over to the door and locked it. He gestured at the guards, who spread themselves around the walls, their guns aimed inward. He was shaking ever so faintly and his eyes glittered as with fever. "Sit down," he said. "There!"

Dalgetty took the indicated armchair. It was deep and soft. It would be hard to spring out of quickly. Elena took a seat opposite him, poised on its edge, the tommy-gun in her lap. It was suddenly very still in the room.

Bancroft went over to the desk and fumbled with a humidor. He didn't look up. "So you caught him," he said.

"Yes," replied Elena. "After he caught me first."

"How did you—turn the tables?" Bancroft took out a cigar and bit the end off savagely. "What happened?"

"I was in a cave, resting," she said tonelessly. "He rose out of the water and grabbed me. He'd been hiding underneath longer than anybody would have thought possible. He forced me out to a rock in the bay there—you know it? We hid till sundown, when he opened up on your men on that beach. He killed them all.

"I'd been tied but I'd managed to rub the strips loose. It was just a piece off his shirt he tied me with. While he was shooting I grabbed a stone and clipped him behind the ear. I dragged him to shore while he was still out, took one of the guns lying there and marched him here."

"Good work." Bancroft inhaled raggedly. "I'll see that you get a proper bonus for this, Elena. But what else? You said...."

"Yes." Her gaze was steady on him. "We talked, out there in the bay. He wanted to convince me I should help him. Tom—he isn't human."

"Eh?" Bancroft's heavy form jerked. With an effort he steadied himself. "What do you mean?"

"That muscular strength and speed, and telepathy. He can see in the dark and hold his breath longer than any man. No, he isn't human."

Bancroft looked at Dalgetty's motionless form. The prisoner's eyes clashed with his and it was he who looked away again. "A telepath, did you say?"

"Yes," she answered. "Do you want to prove it, Dalgetty?"

There was stillness in the room. After a moment Dalgetty spoke. "You were thinking, Bancroft, 'All right, damn you, can you read my mind? Go ahead and try it and you'll know what I'm thinking about you.' The rest was obscenities."

"A guess," said Bancroft. There was sweat on his cheeks. "Just a good guess. Try again."

Another pause, then, "'Ten, nine, seven, A, B, M, Z, Z ...' Shall I keep on?" Dalgetty asked quietly.

"No," muttered Bancroft. "No, that's enough. What are you?"

"He told me," put in Elena. "You're going to have trouble believing it. I'm not sure if I believe it myself. But he's from another star."

Bancroft opened his lips and shut them again. The massive head shook in denial.

"He is—from Tau Ceti," said Elena. "They're way beyond us. It's the thing people have been speculating about for the last hundred years."

"Longer, my girl," said Tighe. There was no emotion in his face or voice save a dry humor, but Dalgetty knew what a flame must suddenly be leaping up inside him. "Read Voltaire's Micromegas."

"I've read such fiction," said Bancroft harshly. "Who hasn't? All right, why are they here, what do they want?"

"You could say," spoke Dalgetty, "that we favor the Institute."

"But you've been raised from childhood...."

"Oh yes. My people have been on Earth a long time. Many of them are born here. Our first spaceship arrived in Nineteen Sixty-five." He leaned forward in the chair. "I expected Casimir to be reasonable and help me rescue Dr. Tighe. Since she hasn't done so I must appeal to your own common sense. We have crews on Earth. We know where all our people are at any given time. If necessary I can die to preserve the secret of our presence but in that case you will die too, Bancroft. The island will be bombed."

"I...." The chief looked out the window into the enormity of night. "You can't expect me to—to accept this as if...."

"I've some things to tell you which may change your mind," said Dalgetty. "They will certainly prove my story. Send your men out though. This is only for your ears."

"And have you jump me!" snapped Bancroft.

"Casimir can stay," said Dalgetty, "and anyone else you are absolutely certain can keep a secret and control his own greed."

Bancroft paced once around the room. His eyes flickered back and forth over the watching men. Frightened faces, bewildered faces, ambitious faces—it was a hard decision and Dalgetty knew grimly that his life rested on his and Elena's estimate of Thomas Bancroft's character.

"All right! Humphrey, Zimmermann, O'Brien, stay in here. If that bird moves shoot him. The rest of you wait just outside." They filed out. The door closed behind them. The three guards left posted themselves with smooth efficiency, one at the window and one at either adjoining wall. There was a long quiet.

Elena had to improvise the scheme and think it at Dalgetty. He nodded. Bancroft planted himself before the chair, legs spread wide as if braced for a blow, fists on hips.

"All right," he said. "What do you want to tell me?"

"You've caught me," said Dalgetty, "so I'm prepared to bargain for my life and Dr. Tighe's freedom. Let me show you—" He made a move as if to rise.

"Stay where you are!" snapped Bancroft, and three guns swiveled around to point at the prisoner. Elena backed away until she stood beside the one near the desk.

"As you will." Dalgetty leaned back again, casually shoving his chair a couple of feet. He was now facing the window and, as far as he could tell, sitting exactly on a line between the man there and the man at the farther wall. "The Union of Tau Ceti is interested in seeing that the right kind of civilizations develop on other planets. You could be of value to us, Thomas Bancroft, if you can be persuaded to our side, and the rewards are considerable." His glance went for a moment to the girl and she nodded imperceptibly. "For example...."

The power rushed up in him. Elena clubbed her gun butt and struck the man next to her behind the ear. In the fractional second before the others could understand and react Dalgetty was moving.

The impetus which launched him from the chair sent that heavy padded piece of furniture sliding across the floor to hit the man behind him with a muffled thud. His left fist took Bancroft on the jaw as he went by. The guard at the window had no time to swing his gun back from Elena and squeeze trigger before Dalgetty's hand was on his throat. His neck snapped.

Elena stood over her victim even as he toppled and aimed at the man across the room. The armchair had knocked his rifle aside. "Drop that or I shoot," she said.

Dalgetty snatched up a gun for himself, leveling it at the door. He more than half expected those outside to come rushing in, expected hell would explode. But the thick oak panels must have choked off sound.

Slowly, the man behind the chair let his rifle fall to the floor. His mouth was stretched wide with supernatural fear.

"My God!" Dr. Tighe's long form was erect, shaking, his calm broken into horror. "Simon, the risk...."

"We didn't have anything to lose, did we?" Dalgetty's voice was thick but the abnormal energy was receding from him. He felt a surge of weariness and knew that soon the payment must be made for the way he had abused his body. He looked down at the corpse before him. "I didn't mean to do that," he whispered.

Tighe collected himself with an effort of disciplined will and stepped over to Bancroft. "He's alive, at least," he said. "Oh my God, Simon! You could have been killed so easily."

"I may yet. We aren't out of the woods by any means. Find something to tie these two others up with, will you, Dad?"

The Englishman nodded. Elena's slugged guard was stirring and groaning. Tighe bound and gagged him with strips torn from his tunic. Under the submachine-gun the other submitted meekly enough. Dalgetty rolled them behind a sofa with the one he had slain.

Bancroft was wakening too. Dalgetty located a flask of bourbon and gave it to him. Clearing eyes looked up with the same terror. "Now what?" mumbled Bancroft. "You can't get away—"

"We can damn well try. If it had come to fighting with the rest of your gang we'd have used you as a hostage but now there's a neater way. On your feet! Here, straighten your tunic, comb your hair. Okay, you'll do just as you're told, because if anything goes wrong we'll have nothing at all to lose by shooting you." Dalgetty rapped out his orders.

* * * * *

Bancroft looked at Elena and there was more than physical hurt in his eyes. "Why did you do it?"

"FBI," she said.

He shook his head, still stunned, and shuffled over to the desk visiphone and called the hangar. "I've got to get to the mainland in a hurry. Have the speedster ready in ten minutes. No, just the regular pilot, nobody else. I'll have Dalgetty with me but it's okay. He's on our side now."

They went out the door. Elena cradled her tommy-gun under one arm. "You can go back to the barracks, boys," said Bancroft wearily to the men outside. "It's all been settled."

A quarter hour later Bancroft's private jet was in the air. Five minutes after that he and the pilot were bound and locked in a rear compartment. Michael Tighe took the controls. "This boat has legs," he said. "Nothing can catch us between here and California."

"All right." Dalgetty's tones were flat with exhaustion. "I'm going back to rest, Dad." Briefly his hand rested on the older man's shoulder. "It's good to have you back," he said.

"Thank you, son," said Michael Tighe. "I can't tell you how wonderful it is to be free again."

IX

Dalgetty found a reclining seat and eased himself into it. One by one he began releasing the controls over himself—sensitivities, nerve blocs, glandular stimulation. Fatigue and pain mounted within him. He looked out at the stars and listened to the dark whistle of air with merely human senses.

Elena Casimir came to sit beside him and he realized that his job wasn't done. He studied the strong lines of her face. She could be a hard foe but just as stubborn a friend.

"What do you have in mind for Bancroft?" he asked.

"Kidnapping charges for him and that whole gang," she said. "He won't wriggle out of it, I can guarantee you." Her eyes rested on him, unsure, a little frightened. "Federal prison psychiatrists have Institute training," she murmured. "You'll see that his personality is reshaped your way, won't you?"

"As far as possible," Simon said. "Though it doesn't matter much. Bancroft is finished as a factor to be reckoned with. There's still Bertrand Meade himself, of course. Even if Bancroft made a full confession I doubt that we could touch him. But the Institute has now learned to take precautions against extra-legal methods—and within the framework of the law we can give him cards and spades and still defeat him."

"With some help from my department," Elena said. There was a touch of steel in her voice. "But the whole story of this rescue will have to be played down. It wouldn't do to have too many ideas floating around in the public mind, would it?"

"That's right," he admitted. His head felt heavy, he wanted to rest it on her shoulder and sleep for a century. "It's up to you really. If you submit the right kind of report to your superiors it can all be worked out. Everything else will just be detail. But otherwise you'll ruin everything."

"I don't know." She looked at him for a long while. "I don't know if I should or not. You may be correct about the Institute and the justice of its aims and methods. But how can I be sure, when I don't know what's behind it? How do I know there wasn't more truth than fiction in that Tau Ceti story, that you aren't really the agent of some non-human power quietly taking over all our race?"

At another time Dalgetty might have argued, tried to veil it from her, tried to trick her once again. But now he was too weary. There was a great surrender in him. "I'll tell you if you wish," he said, "and after that it's in your hands. You can make us or break us."

"Go on then." Her tone withdrew into wariness.

"I'm human," he said. "I'm as human as you are. Only I've had rather special training, that's all. It's another discovery of the Institute for which we don't feel the world is ready. It'd be too big a temptation for too many people, to create followers like me." He looked away, into the windy dark. "The scientist is also a member of society and has a responsibility toward it. This—restraint—of ours is one way in which we meet that obligation."

She didn't speak, but suddenly one hand reached over and rested on his. The impulsive gesture brought warmth flooding through him.

"Dad's work was mostly in mass-action psych," he said, making his tone try to cover what he felt, "but he has plenty of associates trying to understand the individual human being as a functioning mechanism. A lot's been learned since Freud, both from the psychiatric and the neurological angle. Ultimately, those two are interchangeable.

"Some thirty years ago one of the teams which founded the Institute learned enough about the relationship between the conscious, subconscious and involuntary minds to begin practical tests. Along with a few others I was a guinea pig. And their theories worked.

"I needn't go into the details of my training. It involved physical exercises, mental practice, some hypnotism, diet and so on. It went considerably beyond the important Synthesis education which is the most advanced thing known to the general public. But its aim—only partially realized as yet—its aim was simply to produce the completely integrated human being."

Dalgetty paused. The wind flowed and muttered beyond the wall.

"There is no sharp division between conscious and subconscious or even between those and the centers controlling involuntary functions," he said. "The brain is a continuous structure. Suppose, for instance, that you become aware of a runaway car bearing down on you.

"Your heartbeat speeds up, your adrenalin output increases, your sight sharpens, your sensitivity to pain drops—it's all preparation for fight or flight. Even without obvious physical necessity the same thing can happen on a lesser scale—for example when you read an exciting story. And psychotics, especially hysterics, can produce some of the damnedest physiological symptoms you ever saw."

"I begin to understand," she whispered.

"Rage or fear brings abnormal strength and fast reaction. But the psychotic can do more than that. He can show physical symptoms like burns, stigmata or—if female—false pregnancy. Sometimes he becomes wholly insensitive in some part of his body via a nerve bloc. Bleeding can start or stop without apparent cause. He can go into a coma or he can stay awake for days without getting sleepy. He can—"

"Read minds?" It was a defiance.

"Not that I know of." Simon chuckled. "But human sense organs are amazingly good. It only takes three or four quanta to stimulate the visual purple—a little more actually because of absorption by the eyeball itself. There have been hysterics who could hear a watch ticking twenty feet away that the normal person could not hear at one foot. And so on.

"There are excellent reasons why the threshold of perception is relatively high in ordinary people—the stimuli of usual conditions would be blinding and deafening, unendurable, if there weren't a defense." He grimaced. "I know!"

"But the telepathy?" Elena persisted.

"It's been done before," he said. "Some apparent cases of mindreading in the last century were shown to be due to extremely acute hearing. Most people sub-vocalize their surface thoughts. With a little practice a person who can hear those vibrations can learn to interpret them. That's all." He smiled with one side of his mouth. "If you want to hide your thoughts from me just break that habit, Elena."

She looked at him with an emotion he could not quite recognize. "I see," she breathed. "And your memory must be perfect too, if you can pull any datum out of the subconscious. And you can—do everything, can't you?"

"No," he said. "I'm only a test case. They've learned a great deal by observing me but the only thing that makes me unusual is that I have conscious control of certain normally subconscious and involuntary functions. Not all of them by a long shot. And I don't use that control any more than necessary.

"There are sound biological reasons why man's mind is so divided and plenty of penalties attached to a case like mine. It'll take me a couple of months to get back in shape after this bout. I'm due for a good old-fashioned nervous breakdown and while it won't last long it won't be much fun while it does last."

The appeal rose in his eyes as he watched Elena. "All right," he said. "Now you have the story. What are you going to do about it?"

For the first time she gave him a real smile. "Don't worry," she said, "Don't worry, Simon."

"Will you come hold my hand while I'm recuperating?" he asked anxiously.

"I'm holding it now, you fool," Elena answered.

Dalgetty chuckled happily. Then he went to sleep.

* * * * *

THE END