"I will, of course," she answered. "I've done it dozens of times." She seemed to be half-expecting him to doubt her competence, but Franklin knew better than to do so. Indra, he had already discovered, was a very levelheaded girl-perhaps too levelheaded. If she said she could do a job, that was that.

There was still, however, one other point to be settled. The cats could take four people; who would the other two be?

Neither Indra nor Franklin actually voiced the final decision. It hovered in the air while they discussed various possible companions, starting with Don and working down the list of Indra's friends at the lab. Presently the conversation died out into one of those portentous pauses which can sometimes occur even in a roomful of chattering people.

In the sudden silence, each realized that the other was thinking the same thought, and that a new phase had begun in their relationship. They would take no one with them to Masthead; for the first time, they would have the solitude that had never been possible here. That this could lead only to one logical conclusion they refused to admit, even to themselves, the human mind having a remarkable capacity for self-deceit.

It was well into the afternoon before they were able to make all their arrangements and escape. Franklin felt very guilty about Don, and wondered what his reactions would be when he found out what had happened. He would probably be mortified, but he was not the sort to hold a grudge and he would take it like a man.

Indra had thought of everything. Food, drinks, sunburn lotion, towels-she had overlooked nothing that such an expedition might need. Franklin was impressed by her thoroughness, and was amused to find himself thinking that so competent a woman would be very useful to have around the house. Then he reminded himself hastily that women who were too efficient were seldom happy unless they ran their husbands' lives as well as their own.

There was a steady wind blowing from the mainland, and the cat bounded across the waves like a living creature. Franklin had never before been in a sailing boat, and he found the experience an exhilarating one. He lay back on the worn but comfortable padding of the open c.o.c.kpit, while Heron Island receded into the distance at an astonishing speed. It was restful to watch the twin creamy wakes trace their pa.s.sage across the sea, and to caress with the eye the straining, power-filled curves of the sails. With a mild and fleeting regret, Franklin wished that all man's machines could be as simple and efficient as this one. What a contrast there was between this vessel and the crowded complexities of the subs he was now learning to handle! The thought pa.s.sed swiftly; there were some tasks which could not be achieved by simple means, and one must accept the fact without complaint.

On their left, they were now skirting the long line of rounded coral boulders which centuries of storms had cast up upon the edge of the Wistari Reef. The waves were breaking against the submerged ramparts with a relentless and persistent fury which had never impressed Franklin so much as now. He had seen them often enough before-but never from so close at hand, in so frail a craft.

The boiling margin of the reef fell astern; now they had merely to wait while the winds brought them to their goal. Even if the wind failed-which was most unlikely-they could still make the trip on the little auxiliary hydrojet engine, though that would only be used as a last resort. It was a matter of principle to return with a full fuel tank.

Although they were now together and alone for almost the first time since they had met, neither Franklin nor Indra felt any need to talk There seemed a silent communion between them which they did not wish to break with words, being content to share the peace and wonder of the open sea and the open sky. They were enclosed between two hemispheres of flawless blue, clamped together at the misty rim of the horizon, and nothing else of the world remained. Even time seemed to have faltered to a stop; Franklin felt he could lie here forever, relaxing in the gentle motion of the boat as it skimmed effortlessly over the waves.

Presently a low, dark cloud began to solidify, then to reveal itself as a tree-clad island with its narrow sandy sh.o.r.e and inevitable fringing reef. Indra bestirred herself and began to take an active interest in navigation once more, while Franklin looked rather anxiously at the breakers which seemed to surround the island in one continuous band.

"How are we going to get in?" he asked.

"Round the lee side; it won't be rough there, and the tide should be high enough for us to go in across the reef. If it isn't, we can always anchor and wade ash.o.r.e."

Franklin was not altogether happy about so casual an approach to what seemed a serious problem, and he could only hope that Indra really did know what she was doing. If she made a mistake, they might have an uncomfortable though not particularly dangerous swim ahead, followed after a long wait by an ignominious rescue when someone came from the lab to look for them.

Either it was easier than it appeared to an anxious novice, or else Indra's seamanship was of a high order. They circled halfway around the island, until they came to a spot where the breakers subsided into a few choppy waves. Then Indra turned the prow of the cat toward the land, and headed straight for sh.o.r.e.

There were no sounds of grinding coral or splintering plastic. Like a bird, the catamaran flew in across the narrow edge of the reef, now clearly visible just below the broken and unsettled water. It skimmed past this danger zone, and then was over the peaceful surface of the lagoon, seeming to gain speed as it approached the beach. Seconds before impact, Indra furled the mainsail. With a soft thud, the vessel hit the sand and coasted up the gentle slope, coming to rest with more than half its length above the water line.

"Here we are," said Indra. "One uninhabited coral island, in full working order." She seemed more relaxed and light-hearted than Franklin had ever before seen her; he realized that she, too, had been working under pressure and was glad to escape from the daily routine for a few hours. Or was it the stimulating effect of his company that was turning her from a serious student into a vivacious girl? Whatever the explanation, he liked the change. They climbed out of the boat and carried their gear up the beach into the shade of the coconut palms, which had been imported into these islands only during the last century to challenge the predominance of the Pisonia and the stilt-rooted panda.n.u.s. It seemed that someone else had also been here recently, for curious tracks apparently made by narrow-gauge caterpillar treads marched up out of the water and vanished inland. They would have been quite baffling to anyone who did not know that the big turtles had been coming ash.o.r.e to lay their eggs.

As soon as the cat had been made secure, Franklin and Indra began a tour of exploration. It was true that one coral island was almost exactly the same as another; the same pattern was repeated endlessly over and over again, with few variations. Yet even when one was aware of that, and had landed on dozens of islands, every new one presented a fresh challenge which had to be accepted.

They began the circ.u.mnavigation of their little world, walking along the narrow belt of sand between the forest and the sea. Sometimes, when they came to a clearing, they made short forays inland, deliberately trying to lose themselves in the tangle of trees so that they could pretend that they were in the heart of Africa and not, at the very most, a hundred yards from the sea.

Once they stopped to dig with their hands at the spot where one of the turtle tracks terminated on a flat-ended sand dune. They gave up when they were two feet down and there was still no sign of the leathery, flexible eggs. The mother turtle, they solemnly decided, must have been making false trails to deceive her enemies. For the next ten minutes, they elaborated this fantasy into a startling thesis on reptile intelligence, which, far from gaining Indra new qualifications, would undoubtedly have cost her the degree she already possessed.

Inevitably the time came when, having helped each other over a patch of rough coral, their hands failed to separate even though the path was smooth once more. Neither speaking, yet each more conscious of the other's presence than they had ever been before, they walked on in the silence of shared contentment.

At a leisurely stroll, pausing whenever they felt like it to examine some curiosity of the plant or animal world, it took them almost two hours to circ.u.mnavigate the little island. By the time they had reached the cat they were very hungry, and Franklin began to unpack the food hamper with unconcealed eagerness while Indra started working on the stove.

"Now I'm going to brew you a billy of genuine Australian tea," she said. Franklin gave her that twisted, whimsical smile which she found so attractive.

"It will hardly be a novelty to me," he said. "After all, I was born here."

She stared at him in astonishment which gradually turned to exasperation. "Well, you might have told me!" she said. "In fact, I really think-" Then she stopped, as if by a deliberate effort of will, leaving the uncompleted sentence hanging in mid-air. Franklin had no difficulty in finishing it. She had intended to say, "It's high time you told me something about yourself, and abandoned all this silly reticence."

The truth of the unspoken accusation made him flush, and for a moment some of his carefree happiness-the first he had known for so many months-drained away. Then a thought struck him which he had never faced before, since to do so might have jeopardized his friendship with Indra. She was a scientist and a woman, and therefore doubly inquisitive. Why was it that she had never asked him any questions about his past life? There could be only one explanation. Dr. Myers, who was un.o.btrusively watching over him despite the jovial pretense that he was doing nothing of the sort, must have spoken to her.

A little more of his contentment ebbed as he realized that Indra must feel sorry for him and must wonder, like everyone else, exactly what had happened to him. He would not, he told himself bitterly, accept a love that was founded on pity.

Indra seemed unaware of his sudden brooding silence and the conflict that now disturbed his mind. She was busy filling the little stove by a somewhat primitive method that involved siphoning fuel out of the hydrojet's tank, and Franklin was so amused by her repeated failures that he forgot his momentary annoyance. When at last she had managed to light the stove, they lay back under the palms, munching sandwiches and waiting for the water to boil. The sun was already far down the sky, and Franklin realized that they would probably not get back to Heron Island until well after nightfall. However, it would not be dark, for the moon was nearing full, so even without the aid of the local beacons the homeward journey would present no difficulties.

The billy-brewed tea was excellent, though doubtless far too anemic for any old-time swagman. It washed down the remainder of their food very efficiently, and as they relaxed with sighs of satisfaction their hands once again found each other. Now, thought Franklin, I should be perfectly content. But he knew that he was not; something that he could not define was worrying him.

His unease had grown steadily stronger during the last few minutes, but he had tried to ignore it and force it down into his mind. He knew that it was utterly ridiculous and irrational to expect any danger here, on this empty and peaceful island. Yet little warning bells were ringing far down in the labyrinths of his brain, and he could not understand their signals.

Indra's casual question came as a welcome distraction. She was staring intently up into the western sky, obviously searching for something.

"Is it really true, Walter," she asked, "that if you know where to look for her you can see Venus in the daytime? She was so bright after sunset last night that I could almost believe it."

"It's perfectly true," Franklin answered. "In fact, it isn't even difficult. The big problem is to locate her in the first place; once you've done that, she's quite easy to see."

He propped himself up against a palm trunk, shaded his eyes from the glare of the descending sun, and began to search the western sky with little hope of discovering the elusive silver speck he knew to be shining there. He had noticed Venus dominating the evening sky during the last few weeks, but it was hard to judge how far she was from the sun when both were above the horizon at the same time.

Suddenly-unexpectedly-his eyes caught and held a solitary silver star hanging against the milky blue of the sky. "I've found her!" he exclaimed, raising his arm as a pointer. Indra squinted along it, but at first could see nothing.

"You've got spots before the eyes," she taunted.

"No-I'm not imagining things. Just keep on looking," Franklin answered, his eyes still focused on the dimensionless star which he knew he would lose if he turned away from it even for a second.

"But Venus can't can't be there," protested Indra. "That's much too far north." be there," protested Indra. "That's much too far north."

In a single, sickening instant Franklin knew that she was right. If he had any doubt, he could see now that the star he was watching was moving swiftly across the sky, rising out of the west and so defying the laws which controlled all other heavenly bodies.

He was staring at the s.p.a.ce Station, the largest of all the satellites now circling Earth, as it raced along its thousand-mile-high orbit. He tried to turn his eyes away, to break the hypnotic spell of that man-made, unscintillating star. It was as if he was teetering on the edge of an abyss; the terror of those endless, trackless wastes between the worlds began to invade and dominate his mind, to threaten the very foundations of his sanity.

He would have won the struggle, no more than a little shaken, had it not been for a second accident of fate. With the explosive suddenness with which memory sometimes yields to persistent questioning, he knew what it was that had been worrying him for the last few minutes. It was the smell of the fuel that Indra had siphoned from the hydrojet -the unmistakable, slightly aromatic tang of synthene. And crowding hard upon that recognition was the memory of where he had last met that all-too-familiar odor.

Synthene-first developed as a rocket propellant-now obsolete like all other chemical fuels, except for low-powered applications like the propulsion of s.p.a.ce suits.

s.p.a.ce suits.

It was too much; the double a.s.sault defeated him. Both sight and smell had turned traitor in the same instant. Within seconds, the patiently built dikes which now protected his mind went down before the rising tide of terror.

He could feel the Earth beneath him spinning dizzily through s.p.a.ce. It seemed to be whirling faster and faster on its axis, trying to hurl him off like a stone from a sling by the sheer speed of its rotation. With a choking cry, he rolled over on his stomach, buried his face in the sand, and clung desperately to the rough trunk of the palm. It gave him no security; the endless fall began again.... Chief Engineer Franklin, second in command of the Arcturus, Arcturus, was in s.p.a.ce once more, at the beginning of the nightmare he had hoped and prayed he need never retrace. was in s.p.a.ce once more, at the beginning of the nightmare he had hoped and prayed he need never retrace.

Seven.

IN THE FIRST shock of stunned surprise, Indra sat staring foolishly at Franklin as he groveled in the sand and wept like a heartbroken child. Then compa.s.sion and common sense told her what to do; she moved swiftly to his side and threw her arms around his heaving shoulders.

"Walter!" she cried. "You're all right-there's nothing to be afraid of!"

The words seemed flat and foolish even as she uttered them, but they were the best she had to offer. Franklin did not seem to hear; he was still trembling uncontrollably, still clinging to the tree with desperate determination. It was pitiful to see a man reduced to such a state of abject fear, so robbed of all dignity and pride. As Indra crouched over him, she realized that between his sobs he was calling a name- and even at such a moment as this she could not depress a stab of jealousy. For it was the name of a woman; over and over again, in a voice so low as to be barely audible, Franklin would whisper "Irene!" and then be convulsed by a fresh paroxysm of weeping.

There was something here beyond Indra's slight knowledge of medicine. She hesitated for a moment, then hurried to the catamaran and broke open its little first-aid kit. It contained a vial of potent pain-killing capsules, prominently labeled only one to be taken at any time, and with some difficulty she managed to force one of these into Franklin's mouth. Then she held him in her arms while his tremors slowly subsided and the violence of the attack ebbed away.

It is hard to draw any line between compa.s.sion and love. If such a division exists, Indra crossed it during this silent vigil. Franklin's loss of manhood had not disgusted her; she knew that something terrible indeed must have happened in his past to bring him to this state. Whatever it was, her own future would not be complete unless she could help him fight it.

Presently Franklin was quiet, though apparently still conscious. He did not resist when she rolled him over so that his face was no longer half-buried in the sand, and he relaxed his frenzied grip upon the tree. But his eyes were empty, and his mouth still moved silently though no words came from it "We're going home," whispered Indra, as if soothing a frightened child. "Come along-it's all right now."

She helped him to his feet, and he rose unresistingly. He even a.s.sisted her, in a mechanical way, to pack their equipment and to push the catamaran off the beach. He seemed nearly normal again, except that he would not speak and there was a sadness in his eyes that tore at Indra's heart.

They left the island under both sail and power, for Indra was determined to waste no time. Even now it had not occurred to her that she might be in any personal danger, so many miles from any help, with a man who might be mad. Her only concern was to get Franklin back to medical care as quickly as she could.

The light was failing fast; the sun had already touched the horizon and darkness was ma.s.sing in the east. Beacons on the mainland and the surrounding islands began, one by one, to spring to life. And, more brilliant than any of them, there in the west was Venus, which had somehow caused all this trouble....

Presently Franklin spoke, his words forced but perfectly rational.

"I'm very sorry about this, Indra," he said. "I'm afraid I spoiled your trip." "Don't be silly," she answered. "It wasn't your fault. Just take it easy-don't talk unless you want to." He relapsed into silence, and spoke no more for the rest of the voyage. When Indra reached out to hold his hand again, he stiffened defensively in a way which said, without actually rejecting her, that he would prefer no such contact. She felt hurt, but obeyed his unspoken request. In any event, she was busy enough picking out the beacons as she made the tricky pa.s.sage between the reefs.

She had not intended to be out as late as this, even though the rising moon was now flooding the sea with light. The wind had freshened, and all too close at hand the breakers along the Wistari Reef were appearing and vanishing in deadly lines of luminous, ghostly white. She kept one eye on them, and the other on the winking beacon that marked the end of the Heron jetty. Not until she could see the jetty itself and make out the details of the island was she able to relax and give her attention once more to Franklin.

He appeared almost normal again when they had berthed the catamaran and walked back to the lab. Indra could not see his expression, for there were no lights here on this part of the beach, and the palms shaded them from the moon. As far as she could tell, his voice was under full control when he bade her good night.

"Thank you for everything, Indra. No one could have done more."

"Let me take you to Dr. Myers right away. You've got to see him."

"No-there's nothing he can do. I'm quite all right now- it won't happen again."

"I still think you should see him. I'll take you to your room and then go and call him."

Franklin shook his head violently.

"That's one thing I don't want you to do. Promise me you won't call him."

Sorely troubled, Indra debated with her conscience. The wisest thing to do, she was sure, was to make the promise- and then to break it. Yet if she did so, Franklin might never forgive her. In the end, she compromised.

"Will you go and see him yourself, if you won't let me take you?"

Franklin hesitated before answering. It seemed a shame that his parting words with this girl, whom he might have loved, should be a lie. But in the drugged calm that had come upon him now he knew what he must do.

"I'll call him in the morning-and thanks again." Then he broke away, with a fierce finality, before Indra could question him further. She watched him disappear into the darkness, along the path that led to the training and administration section. Happiness and anxiety were contending for her soul-happiness because she had found love, anxiety because it was threatened by forces she did not understand. The anxiety resolved itself into a single nagging fear: Should she have insisted, even against his will, that Franklin see Dr. Myers at once?

She would have had no doubt of the answer could she have watched Franklin double back through the moonlit forest and make his way, like a man in a waking dream, to the dock from which had begun all his journeys down into the sea.

The rational part of his mind was now merely the pa.s.sive tool of his emotions, and they were set upon a single goal. He had been hurt too badly for reason to control him now; like an injured animal, he could think of nothing but the abating of his pain. He was seeking the only place where for a little while he had found peace and contentment The jetty was deserted as he made the long, lonely walk out to the edge of the reef. Down in the submarine hangar, twenty feet below the water line, he made his final preparations with as much care as he had ever done on his many earlier trips. He felt a fleeting sense of guilt at robbing the bureau of some fairly valuable equipment and still more valuable training time; but it was not his fault that he had no other choice.

Very quietly, the torp slipped out beneath the submerged archway and set course for the open sea. It was the first time that Franklin had ever been out at night; only the fully enclosed subs operated after darkness, for night navigation involved dangers which it was foolhardy for unprotected men to face. That was the least of Franklin's worries as he set the course he remembered so well and headed out into the channel that would lead him to the sea.

Part of the pain, but none of the determination, lifted from his mind. This was where he belonged; this was where he had found happiness. This was where he would find oblivion.

He was in a world of midnight blue which the pale rays of the moon could do little to illumine. Around him strange shapes moved like phosph.o.r.escent ghosts, as the creatures of the reef were attracted or scattered by the sound of his pa.s.sing. Below him, no more than shadows in a deeper darkness, he could see the coral hills and valleys he had grown to know so well. With a resignation beyond sadness, he bade them all adieu.

There was no point in lingering, now that his destiny was clear before him. He pushed the throttle full down, and the torpedo leaped forward like a horse that had been given the spur. The islands of the Great Barrier Reef were falling swiftly behind him, and he was heading out into the Pacific at a speed which no other creature of the sea could match.

Only once did he glance up at the world he had abandoned. The water was fantastically clear, and a hundred feet above his head he could see the silver track of the moon upon the sea, as few men could ever have witnessed it before. He could even see the hazy, dancing patch of light that was the moon itself, refracted through the water surface yet occasionally freezing, when the moving waves brought a moment of stability, into a perfect, flawless image.

And once a very large shark-the largest he had ever seen-tried to pursue him. The great streamlined shadow, leaving its phosph.o.r.escent wake, appeared suddenly almost dead ahead of him, and he made no effort to avoid it. As it swept past he caught a glimpse of the inhuman, staring eye, the slatted gills, and the inevitable retinue of pilot fish and remora. When he glanced back the shark was following him -whether motivated by curiosity, s.e.x, or hunger he neither knew nor cared. It remained in sight for almost a minute before his superior speed left it behind. He had never met a shark that had reacted in this way before; usually they were terrified of the turbine's warning scream. But the laws that ruled the reef during the day were not those that prevailed in the hours of darkness.

He raced on through the luminous night that covered half the world, crouching behind his curved shield for protection against the turbulent waters he was sundering in his haste to reach the open sea. Even now he was navigating with all his old skill and precision; he knew exactly where he was, exactly when he would reach his objective-and exactly how deep were the waters he was now entering. In a few minutes, the sea bed would start slanting sharply down and he must say his last farewell to the reef.

He tilted the nose of the torp imperceptibly toward the depths and at the same time cut his speed to a quarter. The mad, roaring rush of waters ceased; he was sliding gently down a long, invisible slope whose end he would never see.

Slowly the pale and filtered moonlight began to fade as the water thickened above him. Deliberately, he avoided looking at the illuminated depth gauge, avoided all thought of the fathoms that now lay overhead. He could feel the pressure on his body increasing minute by minute, but it was not in the least unpleasant. Indeed, he welcomed it; he gave himself, a willing sacrifice, gladly into the grasp of the great mother of life.

The darkness was now complete. He was alone, driving through a night stranger and more palpable than any to be found upon the land. From time to time he could see, at an unguessable distance below him, tiny explosions of light as the unknown creatures of the open sea went about their mysterious business. Sometimes an entire, ephemeral galaxy would thrust forth and within seconds die; perhaps that other galaxy, he told himself, was of no longer duration, of no greater importance, when seen against the background of eternity.

The dreamy sleep of nitrogen narcosis was now almost upon him; no other human being, using a compressed-air lung alone, could ever have been so deep and returned to tell the tale. He was breathing air at more than ten times normal pressure, and still the torpedo was boring down into the light-less depths. All responsibility, all regrets, all fears had been washed away from his mind by the blissful euphoria that had invaded every level of consciousness.

And yet, at the very end, there was one regret. He felt a mild and wistful sadness that Indra must now begin again her search for the happiness he might have given her.

Thereafter there was only the sea, and a mindless machine creeping ever more slowly down to the hundred-fathom line and the far Pacific wastes.

Eight.

THERE WERE FOUR people in the room, and not one of them was talking now. The chief instructor was biting his lip nervously, Don Burley sat looking stunned, and Indra was trying not to cry. Only Dr. Myers seemed fairly well under control, and was silently cursing the fantastic, the still inexplicable bad luck that had brought this situation upon them. He would have sworn that Franklin was well on the road to recovery, well past any serious crisis. And now this!

"There's only one thing to do," said the chief instructor suddenly. "And that's to send out all our underwater craft on a general search."

Don Burley stirred himself, slowly and as if carrying a great weight upon his shoulders.

"It's twelve hours now. In that time he could have covered five hundred miles. And there are only six qualified pilots on the station."

"I know-it would be like looking for a needle in a haystack. But it's the only thing we can do."

"Sometimes a few minutes of thought can save a good many hours of random searching," said Myers. "After half a day, a little extra time will make no difference. With your permission, I'd like to have a private talk with Miss Langenburg."

"Of course-if she agrees."

Indra nodded dumbly. She was still blaming herself bitterly for what had happened-for not going to the doctor immediately when they had returned to the island. Her intuition had failed her then; now it told her that there was no possibility of any hope, and she could only pray that it was wrong again.

"Now, Indra," said Myers kindly when the others had left the room, "if we want to help Franklin we've got to keep our heads, and try to guess what he's done. So stop blaming yourself-this isn't your fault. I'm not sure if it's anyone's fault."