Fourteen minutes- Was he moving at all, though? He couldn't tell. Maybe he wasn't. The car's mechanism was silent; and he had no reference points. What if I'm stuck? he wondered. Just sitting here in the dark, no way to tell where I am, what's happening, how much time is passing? Fifteen minutes, twenty, half an hour? Until I've passed whatever limit my sanity can stand, and then- There's always the abort switch, though.

But suppose it doesn't work? What if I press it ~and the lights don't come on?

I could test it, I suppose. Just to see- Fatty is a coward! Fatty is a coward!

No. No. Don't touch it. Once you turn the lights on you won't be able to turn them off again. You mustn't use the abort switch, or they'll know-they'll all know- Fatty is a coward, Fatty is a coward- Suddenly, astonishingly, he hurled the abort switch into the darkness. There was a tiny sound as it fell-somewhere. Then silence again. His hand felt terribly empty.

The Darkness- The Darkness- There was no end to it. He was tumbling through an infinite abyss. Falling and falling and falling into the night, the endless night, the all-devouring black- Breathe deeply. Stay calm.

What if there '~c permanent mental damage?

Stay calm, he told himself. You'll be all right. You've got maybe eleven minutes more of this at the worst, maybe only six or seven. The suns are shining out there. Six or seven minutes and you'll never be in Darkness again, not if you live to be a thousand.

The Darkness- Oh, God, the Darkness- Calm. Calm. You're a very stable man, Sheerin. You're extremely sane. You were sane when you went into this thing and you'll be sane when you come out.

Tick. Tick. Tick. Every second gets you closer to the exit. Or does it? This ride may never end. I could be in here forever. Tick. Tick. Tick. Am I moving? Do I have five minutes left, or five seconds, or is this still the first minute?

Tick. Tick.

Why don ~t they let me out? Can 't they tell bow I'm suffering in here?

They don't want to let you out. They'll never let you out. They're going to-

Suddenly, a stabbing pain between his eyes. An explosion of agony in his skull.

What's that?

Light!

Could it be? Yes. Yes.

Thank God. Light, yes! Thank any god that might ever have existed!

He was at the end of the Tunnel! He was coming back to the station! It must be. Yes. Yes. His heartbeat, which had become a panicky thunder, was starting to return to normal. His eyes, adjusting now to the return of normal conditions, began to focus on familiar things, blessed things, the stanchions, the platform, the little window in the control booth- Cubello, Kelaritan, watching him.

He felt ashamed now of his cowardice. Pull yourself together, Sheerin. It wasn 't so bad, really. You 're all right. You aren 't lying in the bottom of the car sucking your thumb and whimpering. It was scary, it was terrifying, but it didn 't destroy you-it wasn 't actually anything you couldn 't handle- "Here we go. Give us your hand, Doctor. Up-up-"

They hauled him to a standing position and steadied him as he clambered out of the car. Sheerin sucked breath deep down into his lungs. He ran his hand across his forehead, wiping away the streaming perspiration.

"The little abort switch," he murmured. "I seem to have lost it somewhere-"

"How are you, Doctor?" Kelaritan asked. "How was it?"

Sheerin teetered. The hospital director caught him by the arm, steadying him, but Sheerin indignantly brushed him away. He wasn't going to let them think that those few minutes in the Tunnel had gotten to him.

But he couldn't deny that he had been affected. Try as he might, there was no way to hide that. Not even from himself.

No force in the world could ever get him to take a second trip through that Tunnel, he realized.

"Doctor? Doctor?"

"I'm-all-right-" he said thickly.

"He says he's all right," came the lawyer's voice. "Stand back. Let him alone."

"His legs are wobbling," Kelaritan said. "He's going to fall."

"No," Sheerin said. "Not a chance. I'm fine, I tell you!"

He lurched and staggered, regained his balance, lurche again. Sweat poured from every pore he had. He glanced ove his shoulder, saw the mouth of the Tunnel, and shudderec Turning away from that dark cave, he pulled his shoulders u high, as if he would have liked to hide his face between then

"Doctor?" Kelaritan said doubtfully.

No use pretending. This was foolishness, this vain and stut born attempt at heroism. Let them think he was a coward. L them think anything. Those fifteen minutes had been the wor5 nightmare of his life. The impact of it was still sinking in, an sinking in, and sinking in.

"It was-powerful stuff," he said. "Very powerful. Very di~ turbing."

"But you're basically all right, isn't that so?" the lawyer sai eagerly "A little shaken, yes Who wouldn't be, going mt Darkness~ But basically okay As we knew you'd be It's only few, a very few, who undergo any sort of harmful-"

"No," Sheerin said The lawyer's face was like that of a grir ning gargoyle in front of him Like the face of a demon H couldn't bear the sight of it But a good dose of the truth woul exorcise the demon No need to be diplomatic, Sheen thought Not when talking with demons -"It's impossible fc anyone to go through that thing without being at grave risi I'm certain of it now. Even the strongest psyche will take terrible battering, and the weak ones will simply crumble I you open that ride again, you'll have every mental hospital 1 four provinces full up within six months"

"On the contrary, Doctor-"

"Don't 'on the contrary' me! Have you been in the Tunne Cubell& No, I didn't think so But I have You're paying fc my professional opinion: you might as well have it right no~ The Tunnel's deadly. It's a simple matter of human natun

Darkness is more than most of us can handle, and that's nevc going to change, so long as we've got a sun left burning in th sky. Shut the Tunnel down for good, Cubello! In the name c sanity, man, shut the thing down! Shut it down!"

Parking his motor scooter in the faculty lot just below the Observatory dome, Beenay went jogging quickly up the footpath that led to the main entrance of the huge building. As he began to ascend the wide stone steps of the entranceway itself he was startled to hear someone calling his name from above.

"Beenay! So you are here after all."

The astronomer looked up. The tall, heavyset, powerful figure of his friend Theremon 762 of the Saro City Chronicle stood framed in the great door of the Observatory.

"Theremon? Were you looking for me?"

"I was. But they told me you weren't due to show up here for another couple of hours. And then, just as I was- leaving, there you were anyway. Talk about serendipity!"

Beenay trotted up the last few steps, and they gave each other a quick hug. He had known the newspaperman some three or four years, ever since the time Theremon had come to the Observatory to interview some scientist, any scientist, about the latest manifesto of the crackpot Apostles of Flame group. Gradually he and Theremon had become close friends, even though Theremon was some five years older and came out of a rougher, worldlier background. Beenay liked the idea of having a friend who had no involvement whatsoever in university politics; and Theremon was delighted to know someone who wasn't at all interested in exploiting him for his considerable journalistic influence.

"Is something wrong?" Beenay asked.

"Not in the least. But I need to get you to do the Voice of Science routine again. Mondior's made another of his famous 'Repent, repent, doom is coming' speeches. Now he says he's ready to reveal the exact hour when the world will be destroyed. In case you're interested, it's going to happen next year on the nineteenth of Theptar, as a matter of fact."

"That madman! It's a waste of space printing anything about him. Why does anyone pay the slightest bit of attention to the Apostles, anyway?"

Theremon shrugged. "The fact is that people do. A lot of people, Beenay. And~ if Mondior says the end is nigh, I need to get someone like you to stand up and say, 'Not so, brothers and sisters! Have no fear! All is well!' Or words to that effect. I can count on you, can't I, Beenay?"

"You know you can."

"This evening?"

"This evening? Oh, lord, Theremon, this evening's a real mess. How much of my time do you think you'd have to have?"

"Half an hour? Forty-five minutes?"

"Look," Beenay said, "I've got an urgent appointment right now-that's why I'm here ahead of schedule. After that, I've sworn to Raissta that I'll hustle back home and devote, well, an hour or two to her. We've been on such different tracks lately that we've hardly seen each other at all. And then later in the evening I'm supposed to be here at the Observatory again to supervise taking of a bunch of photographs of-"

"All right," said Theremon. "I see I've picked the wrong time for this. Well, listen, no problem, Beenay. I've got until tomorrow afternoon to turn in my story. What if we talk in the morning?"

"The morning?" Beenay said doubtfully.

"I know morning's an unthinkable concept for you. But what I mean is, I can get back up here at Onos-rise, just as you're finishing up your evening's work. If you could simply manage a little interview with me before you go home to go to sleep-"

"For a friend, Beenay."

Beenay gave the journalist a weary look. "Of course I will. That's not the issue. It's just that I may be so groggy after a whole evening of work that I may not be of any use to you."

Theremon grinned. "That doesn't worry me. I've noticed that you're capable of degroggifying pretty damned quickly when there's anti-scientific nonsense for you to refute. Tomorrow at Onos-rise, then? In your office upstairs?"

"Right."

"A million thanks, pal. I'll owe you one for this."

"Don't mention it."

Theremon saluted and began to head down the steps. "Give my best to that beautiful lady of yours," he called. "And I'll see you in the morning."

"See you in the morning, yes," Beenay echoed.

How odd that sounded. He never saw anybody-or anything-in the morning. But he'd make an exception for Theremon. That was what friendship was all about, wasn't it?

Beenay turned and entered the Observatory.

Inside, all was dimly lit and calm, the familiar hush of the great hall of science where he had spent most of his time since his early university days. But the calm was, he knew, a deceptive one. This mighty building, like the more mundane places of the world, was constantly aswirl with conflicts of all sorts, ranging from the loftiest of philosophical disputes down to the pettiest of trivial feuds, spats, and backbiting intrigues. Astronomers, as a group, were no more virtuous than anyone else.

All the same, the Observatory was a sanctuary for Beenay and for most of the others who worked there-a place where they could leave most of the world's problems behind and devote themselves more or less peacefully to the everlasting struggle to answer the great questions that the universe posed.

He walked swiftly down the long main hall, trying as always without success to muffle the clatter of his boots against the marble floor.

As he invariably did, he glanced quickly into the display cases along the wall to the right and left, where some of the sacred artifacts of the history of astronomy were on perpetual exhibit. Here were the crude, almost comical telescopes that such pioneers as Chekktor and Stanta had used, four or five hundred years before. Here were the gnarled black lumps of meteorites that had fallen from the sky over the centuries, enigmatic reminders of the mysteries that lay behind the clouds. Here were first editions of the great astronomical sky-charts and textbooks, and the time-yellowed manuscripts of some of the epoch-making theoretical works of the great thinkers.

Beenay paused for a moment before the last of those manuscripts, which unlike the others seemed fresh and almost new- for it was only a single generation old, Athor 77's classic codification of the Theory of Universal Gravitation, worked out not very long before Beenay himself had been born. Though he was not a particularly religious man, Beenay stared at that thin sheaf of paper with something very much like reverence, and found himself thinking something very much like a prayer.

The Theory of Universal Gravitation was one of the pillars of the cosmos for him: perhaps the most basic pillar. He couldn't imagine what he would do if that pillar were to fall. And it seemed to him now that the pillar might be tottering.

At the end of the hall, behind a handsome bronze door, was Dr. Athor's own office. Beenay glanced at it quickly and hurried past it, up the stairs. The venerable and still formidable Observatory director was the last person in the world, absolutely the last, that Beenay wanted to see at this moment.

Faro and Yimot were waiting for him upstairs in the Chart Room, where they had arranged to meet.

"Sorry I'm a little late," Beenay said. "It's been a complicated afternoon so far."

They gave him nervous, owlish smiles. What a strange pair they are, he thought, not for the first time. They both came from some backwater farming province-Sithin, maybe, or Gatamber. Faro 24 was short and roly-poly, with a languid, almost indolent way of moving. His general style was easygoing and casual. His friend Yimot 70 was incredibly tall and thin, something like a hinged ladder with arms, legs, and a face, and you practically needed a telescope to see his head, looming up there in the stratosphere above you. Yimot was as tense and twitchy as his friend was relaxed. Yet they were inseparable, always had been. Of all the young graduate students, one notch down the Observatory's table of organization from Beenay's level, they were by far the most brilliant.

"We haven't been waiting long," Yimot said at once.

"Only a minute or two, Dr. Beenay," Faro added.

"Not quite 'doctor' yet, thanks," Beenay said. "I've still got the final inquisition to go through. How did you manage with those computations?"

Yimot said, twitching and jerking his impossibly long legs around, "This is gravitational stuff, isn't it, sir?"

Faro nudged him so vigorously in the ribs with his elbow that Beenay expected to hear the sound of crunching bone.

"That's all right," Beenay said. "Yimot's correct, as a matter of fact." He gave the tall young man a pale smile. "I wanted this to be a purely abstract mathematical exercise for you. But it doesn't surprise me that you were able to figure out the context. You figured it out after you had your result, didn't you?"

"Yes, sir," said Yimot and Faro at the same time. "We ran all the calculations first," Faro said. "Then we took a second look, and the context became apparent," said Yimot.

"Ah. Yes," Beenay said. These kids were sometimes a little unnerving. They were so young-only six or seven years younger than he, as a matter of fact, but he was an assistant professor and they were students, and to him and them both that was a vast barrier. Young as they were, though, they had such extraordinary minds! He wasn't altogether pleased that they had guessed at the conceptual matrix within which these calculations were located. In fact, he wasn't pleased at all. In another few years they'd be right up here on the faculty with him, perhaps competing for the same professorship he hoped to get, and that might not be fun. But he tried not to think about that.

He reached for their printout.

"May I see?" he asked.

Hands fluttering wildly, Yimot handed it over. Beenay scanned the rows of figures, calmly at first, then with rising agitation.

He had been pondering, all year long, certain implications of the Theory of Universal Gravitation, which his mentor Athor had brought to such a summit of perfection. It had been Athor's great triumph, the making of his lofty reputation, to work out the orbital motions of Kalgash and all six of its suns according to rational principles of attractive forces.

Beenay, using modern computational equipment, had been calculating some aspects of Kalgash's orbit around Onos, its primary sun, when to his horror he observed that his figures didn't check out properly in terms of the Theory of Universal Gravitation. The theory said that at the beginning of the present year Kalgash should have been here in relation to Onos, when in undeniable fact Kalgash was there.

The deviation was trivial-a matter of a few decimal places- but that wasn't trivial at all, in the larger sense of things. The Theory of Universal Gravitation was so precise that most people preferred to refer to it as the Law of Universal Gravitation. Its mathematical underpinning was considered impeccable.

But a theory that purports to explain the movements of the world through space~ has no room for even small discrepancies. Either it is complete or it is not complete: no middle way was permissible. And a difference of a few decimal places in a shortrange calculation would widen into a vast abyss, Beenay knew, if more ambitious computations were attempted. What good was the whole Theory of Universal Gravitation if the position that it said Kalgash was going to hold in the sky a century from now turned out to be halfway around Onos from the planet's actual location then?

Beenay had gone over his figures until he was sick of reworking them. The result was always the same.

But what was he supposed to believe?

His numbers, or Athor's towering master scheme?

His piddling notions of astronomy, or the great Athor's profound insight into the fundamental structure of the universe?

He imagined himself standing right on top of the dome of the Observatory, calling out, "Listen to me, everybody! Athor's theory is wrong! I've got the figures right here that disprove it!" Which would bring forth such gales of laughter that he'd be blown clear across the continent. Who was he to set himself up against the titanic Athor? Who could possibly believe that a callow assistant professor had toppled the Law of Universal Gravitation?

And yet-and yet- His eyes raced over the printout sheets that Yimot and Faro had prepared. The calculations on the first two pages were unfamiliar to him; he had set up the data for the two students in such a way that the underlying relationships from which the numbers were derived were not at all obvious, and evidently they had approached the problem in a way that any astronomer trying to compute a planetary orbit would regard as quite unorthodox. Which was exactly what Beenay had wanted. The orthodox ways had led him only into catastrophic conclusions; but he had too much information at his own disposal to be able to work in any other mode but the orthodox ones. Faro and Yimot hadn't been hampered in that fashion.

But as he followed along their line of reasoning, Beenay began to notice a discomforting convergence of the numbers. By the third page they had locked in with his own calculations, which he knew by heart by this time.

And from there on, everything followed in an orderly way, step by step by step, to the same dismaying, shattering, inconceivable, totally unacceptable culminating result.

Beenay looked up at the two students, aghast.

"There's no possibility, is there, that you've slipped up somewhere? This string of integrations here, for example-they look pretty tricky-"

"Sir!" Yimot cried, sounding shocked to the core. His face was bright red and his arms waved about as if moving of their own accord.

Faro said, more placidly, "I'm afraid they're correct, sir. They tally frontwards and backwards."

"Yes. I imagine they do," said Beenay dully. He struggled to conceal his anguish. But his hands were shaking so badly that the printout sheets began to flutter in his grasp. He started to put them down on the table before him, but his wrist jerked uncontrollably in a very Yimot-like gesture and sent them scattering all over the floor.

Faro knelt to pick them up. He gave Beenay a troubled look.

"Sir, if we've upset you in any way-"

"No. No, not at all. I didn't sleep well today, that's the problem. But this is fine work, unquestionably very fine. I'm proud of you. To take a problem like this, one which has utterly no real-world resonance at all, which in fact is in total contradiction of real-world scientific truth, and to follow so methodically to the conclusion required by the data while succeeding in ignoring the fact that the initial premise is absurd-why, it's a splendid job, an admirable demonstration of your powers of logic, a first-rate thought-experiment-"

He saw them exchange quick glances. He wondered if he was fooling them even slightly.

"And now," he went on, "if you'll excuse me, fellows-I have another conference-"

Rolling the damning papers into a tight cylinder, Beenay shoved them under his arm and rushed past them, out the door, down the hall, practically running, heading for the safety and privacy of his own tiny office.

My God, he thought. My God, my God, my God, what have I done? And what will I do now?

He buried his head in his hands and waited for the throbbing to stop. But it didn't seem to be planning to stop. After a moment he sat up and jabbed his finger against the communicator button on his desk.

"Get me the Saro City Chronicle," he told the machine. "Theremon 762."

From the communicator came a long, maddening burst of cracklings and hissings. Then, suddenly, Theremon's deep voice:

"Features desk, Theremon 762."

"Beenay."