"Of course," Beenay said.

"Of course? Why 'of course'?"

"Why-? But everybody sleeps with a godlight!"

"My point exactly. Tell me this: have you ever experienced Darkness, friend Beenay?"

Beenay leaned against the wall next to the big picture window and considered. "No. Can't say I have. But I know what it is. Just-uh-" He made vague motions with his fingers, and then brightened. "Just an absence of light. Like in caves."

"Have you ever been in a cave?"

"In a cave! Of course I haven't been in a cave."

"I thought not. I tried, once, long ago when I was beginning my studies of Darkness-induced disorders. But I got out in a hurry. I went in until the mouth of the cave was just visible as a blur of light, with black everywhere else." Sheerin chuckled pleasantly. "I never thought a person of my weight could run that fast."

Almost defiantly Beenay said, "Well, if it comes to that, I guess I wouldn't have run, if I had been there."

The psychologist smiled gently at the young astronomer.

"Bravely said! I admire your courage, my friend." Turning to Athor, Sheerin said, "May I have your permission, sir, to perform a little psychological experiment?"

"Whatever you wish."

"Thank you." Sheerin looked toward Beenay again. "Do you mind drawing the curtain next to you, friend Beenay?"

Beenay looked surprised. "What for?"

"Just draw the curtain. Then come over here and sit down next to me."

"Well, if you insist-"

Heavy red draperies hung by the windows. Athor couldn't remember a time when they had ever been drawn, and this room had been his office for some forty years. Beenay, with a shrug, reached for the tasseled string and jerked. The red curtain slid across the wide window, the brass rings hissing their way along the crossbar. For a moment the dusk-red light of Dovim could still be seen. Then all was in shadows, and even the shadows became indistinct.

Beenay's footsteps sounded hollowly in the silence as he made his way to the table, and then they stopped halfway.

"I can't see you, Sheerin," he whispered forlornly. "Feel your way," Sheerin ordered in a strained voice. "But I can't see you!" The young astronomer was breathing harshly. "I can't see anything!"

"What did you expect? This is Darkness." Sheerin waited a moment. "Come on. You must know your way around this room even with your eyes closed. Just walk over here and sit down."

The footsteps sounded again, waveringly. There was the sound of someone fumbling with a chair. Beenay's voice came thinly: "Here I am." -

"How do you feel?"

"I'm-ulp--all right."

"You like it, do you?"

A long pause.

"No, Beenay?"

"Not at all. It's awful. It's as if the walls are-" He paused again. "They seem to be closing in on me. I keep wanting to push them away. -But I'm not going mad at all. In fact, I think I'm getting used to it."

"All right. Siferra? What about you?"

"I can take a little Darkness. I've gone crawling around in some underground passages now and then. But I can't say I care for it much."

"Athor?"

"I'm also still surviving. But I think you've proved your point, Dr. Sheerin," said the Observatory head, sharply.

"All right. Beenay, draw the curtains back again." There were cautious footsteps through the dark, the rustle of Beenay's body against the curtain as he felt for the tassel, and then the relief of hearing the curtain's ro-o-osb as it slithered open. The red light of Dovim flooded the room, and with a cry of joy Beenay looked out the window at the smallest of the six suns.

Sheerin wiped the moistness off his forehead with the back of a hand and said shakily, "And that was just a few minutes in a dark room."

"It can be tolerated," said Beenay lightly.

"Yes, a dark room can. At least for a short while. But you all know about the Jonglor Centennial Exposition, don't you? The Tunnel of Mystery scandal? Beenay, I told you the story that evening last summer at the Six Suns Club, when you were with that newspaperman Theremon."

"Yes. I remember. The people who took that ride through Darkness in the amusement park and came out insane."

"Just a mile-long tunnel-with no lights. You got into a little open car and jolted along through Darkness for fifteen minutes. Some who took the ride died of fright. Others came out permanently deranged."

"And why was that? What drove them crazy?"

"Essentially the same thing that was operating on you just now when we had the curtain closed and you thought the walls of the room were crushing in on you in the dark. There's a psychological term for mankind's instinctive fear of the absence of light. We call it 'claustrophobia,' because the lack of light is always tied up with enclosed places, so that the fear of one is fear of the other. You see?"

"And those people of the Tunnel who went crazy?"

"Those people of the Tunnel who went-ah-crazy, to use your word, were those unfortunate ones who didn't have sufficient psychological resilience to overcome the claustrophobia that engulfed them in the Darkness. It was a powerful feeling. Believe me. I took the Tunnel ride myself. You had only a couple of minutes without light just now, and I believe you were fairly upset. Now imagine fifteen minutes."

"But didn't they recover afterward?"

"Some did. But some will suffer for years, or perhaps for the rest of their lives, from claustrophobic fixations. Their latent fear of Darkness and enclosed places has crystallized and become, so far as we can tell, permanent. And some, as I said, died of shock. No recovery for them, eh? That's what fifteen minutes in the dark can do."

"To some people," Beenay said stubbornly. His forehead wrinkled slowly into a frown. "I still don't believe it's going to be that bad for most of us. Certainly not for me."

Sheerin sighed in exasperation. "Imagine Darkness-everywhere. No light, as far as you can see. The houses, the trees, the fields, the earth, the sky-black! And Stars thrown in, if you listen to the preaching of the Apostles-Stars, whatever they are. Can you conceive it?"

"Yes, I can," declared Beenay, even more truculently.

"No! No, you can't!" Sheerin slammed his fist down upon the table in sudden passion. "You're fooling yourself! You can't conceive that. Your brain wasn't built for the concept any more than -Look, Beenay, you're a mathematician, aren't you? Can your brain really and truly conceive of the concept of infinity? Of eternity? You can only talk about it. Reduce it to equations and pretend that the abstract numbers are the reality, when in fact they're just marks on paper. But when you try really to encompass the idea of infinity in your mind you start getting dizzy pretty fast, I'm certain of that. A fraction of the reality upsets you. The same with the little bit of Darkness you just tasted. And when the real thing comes, your brain is going to be presented with a phenomenon outside its limits of comprehension. You'll go insane, Beenay. Completely and permanently. I have no doubt of that whatever!"

Once again there was a sudden terrible silence in the room.

Athor said, at last, "That's your final conclusion, Dr. Sheerin? Widespread insanity?"

"At least seventy-five percent of the population made irrational to a disabling degree. Perhaps eighty-five percent. Perhaps even a hundred percent."

Athor shook his head. "Monstrous. Hideous. A calamity beyond belief. Though I must tell you I feel somewhat the way Beenay does-that we will get through this somehow, that the effects will be less cataclysmic than your opinion would indicate. Old as I am, I can't help feeling a certain optimism, a certain sense of hope-"

Siferra said suddenly, "May I speak, Dr. Athor?"

"Of course. Of course! That's why you're here."

The archaeologist rose and came to the center of the room. "In some ways it surprises me that I'm here at all. When I first discussed my Sagikan Peninsula discoveries with Beenay here, I begged him to keep them absolutely confidential. I was fearful for my scientific reputation, because I saw that the data I had uncovered could very easily be construed as giving support to the most irrational, the most frightening, the mOst dangerous religious movement that exists within our society. I'm speaking, naturally, of the Apostles of Flame.

"But then, when Beenay came back to me a little while later with his new findings, the discovery of the periodicity of these eclipses of Dovim, I knew I had to reveal what I know. I have here photographs and charts of my excavation at the Hill of Thombo, near the Beklimot site on the Sagikan Peninsula. Beenay, you've already seen them, but if you'll be good enough to pass them to Dr. Athor and Dr. Sheerin-"

Siferra waited until they had had a chance to glance at the material. Then she resumed speaking.

"The charts will be easier to understand if you think of the Hill of Thombo as a giant layer cake of ancient settlements, each built upon its immediate predecessor-the youngest one at the top of the hill, naturally. That one is a city of what we call the Beklimot culture. Below it is one built by those same people, we think, in an earlier phase of their civilization, and then down and down and down, for a total of at least seven different periods of settlement, perhaps even more.

"Each of those settlements, gentlemen, came to an end because it was destroyed by fire. You can see, I think, the dark boundaries between the layers. Those are the burn lines-charcoal remnants. My original guess, based purely on an intuitive sense of how long it might have taken for these cities to have arisen, flourished, decayed, and crumbled, is that each of these great fires happened something like two thousand years apart, with the most recent of them taking place about two thousand years ago, just prior to the unfolding of the Beklimot culture that we regard as the beginning of the historical period.

"But charcoal is particularly well suited for radiocarbon dating, which gives us a fairly precise indication of the age of a site. Ever since my Thombo material reached Saro City, our departmental lab has been busy doing radiocarbon analysis, and now we have our figures. I can tell you what they are from memory. The youngest of the Thombo settlements was destroyed by fire two thousand and fifty years ago, with a statistical deviation of plus or minus twenty years. The charcoal from the settlement below that is forty-one hundred years old, with a deviation of plus or minus forty years. The third settlement from the top was destroyed by fire sixty-two hundred years ago, with a deviation of plus or minus eighty years. The fourth settlement down shows a radiocarbon age of eighty-three hundred years, plus or minus a hundred. The fifth-"

"Great gods!" Sheerin cried. "Are they all spaced as evenly as that?"

"Every one of them. The fires occurred at intervals of a little more than twenty centuries. Allowing for the slight inaccuracies that are inevitable in radiocarbon dating, it's still altogether permissible to propose that in fact they took place exactly two thousand and forty-nine years apart. Which, as Beenay has demonstrated, is precisely the frequency at which eclipses of Dovim occur. -And also," Siferra added in a bleak voice, "the length of what the Apostles of Flame call a Year of Godliness, at the end of which the world is supposed to be destroyed by fire."

"An effect of the mass insanity, yes," Sheerin said hollowly. "When the Darkness comes, people will want light-of any sort. Torches. Bonfires. Burn anything! Burn the furniture. Burn houses."

"No," Beenay muttered.

"Remember," Sheerin said, "these people won't be sane. They'll be like small children-but they'll have the bodies of adults and the remnants of the minds of adults. They'll know how to use matches. They just won't remember the consequences of lighting a lot of fires all over the place."

"No," Beenay said again, hopelessly. "No. No." It wasn't a statement of disbelief any longer.

Siferra said, "It could be argued originally that the fires at Thombo were a purely local event-an odd coincidence, such a rigid pattern of regular occurrence over such an immense span of time, but confined only to that one place, perhaps even a peculiar ritual cleansing practiced there. Since no other ancient sites as old as those of Sagikan have been found anywhere else on Kalgash, we couldn't say otherwise. But Beenay's calculations have changed everything. Now we see that every two thousand and forty-nine years the world is-apparently- plunged into Darkness. As Sheerin says, fires would be lit. And would get out of control. Whatever other settlements existed at the time of the Thombo fires, anywhere in the world, would have been destroyed just as the Thombo cities were, and for the same reason. But Thombo is all we have left from the prehistoric era. As the Apostles of Flame say of it, it is a holy place, the place where the gods have made themselves manifest to humanity."

"And perhaps are making themselves manifest once more," said Athor darkly. "By providing us with evidence of the fires of past epochs."

Beenay looked at him. "So you have come to believe the Apostles' teachings, sir?"

To Athor, Beenay's statement seemed almost like a blunt accusation of madness. It was a moment before he could reply.

But then he said, as calmly as he could, "Believe them? No. No, not quite. But they interest me, Beenay. I'm horrified at the need even to pose this question: but what if the Apostles are right? We have clear indications now that Darkness does come at just the two-thousand-and-forty-nine-year interval that they've mentioned in their Book of Revelations. Sheerin here says that the world would go mad if that happened, and we have Siferra's evidence that one small section of the world, at least, did go mad, again and again, its houses swept by fire at that two-thousand-and-forty-nine-year interval that we keep coming upon."

"What are you suggesting, then?" Beenay asked. "That we join the Apostles?"

Again Athor had to fight off anger. "No, Beenay. Simply that we look into their beliefs and see what sort of use we can make of them!"

"Use?" cried Sheerin and Siferra, almost at the same moment.

"Yes! Use!" Athor knotted his great gaunt hands together and swung around to face them all. "Don't you see that the survival of human civilization may depend entirely on the four of us? It comes down to just that, doesn't it? Melodramatic as it sounds, we four are in possession of what is beginning to look like incontrovertible proof that the end of the world is sweeping down on us. Universal Darkness-bringing universal madness-a worldwide conflagration-our cities in flames, our society shattered. But there is already in existence another group that has been predicting, on the basis of who knows what evidence, the very same calamity-to the year, to the day."

"Theptar nineteenth," Beenay murmured.

"Theptar nineteenth, yes. The day when only Dovim will shine in the sky-and, if we are right, Kalgash Two will arrive, rising out of its invisibility to fill our sky and blot out all light. That day, the Apostles tell us, fire will engulf our cities. How do they know? A lucky guess? Mere myth-spinning?"

"Some of what they say makes no sense at all," Beenay pointed out. "For example, they say Stars will appear in the heavens. What are Stars? Where are they going to come from?"

Athor shrugged. "I have no idea. That part of the Apostles' teachings may very well be a fable. But they seem to have some sort of record of past eclipses, out of which they've built their current dire predictions. We need to know more about those records."

"Why us?" Beenay asked.

"Because we-as scientists-can serve as leaders, figures of authority, in the struggle to save civilization that lies ahead," said Athor. "Only if the nature of the danger is made known right here and now does society stand any chance of protecting itself against what's going to happen. But as it is, only the gullible and ignorant pay any heed to the Apostles. Most intelligent, rational folk look upon them the same way we do-as cranks, as fools, as madmen, perhaps as swindlers. What we need to do is persuade the Apostles to share their astronomical and archaelogical data, if they have any, with us. And then we go public. We reveal our findings, and we back them up with the material we receive, if we do, from the Apostles. In essence we form an alliance with them against the chaos that both we and they think is coming. That way we can gain the attention of all strata of society, from the most credulous to the most critical."

"So you want us to stop being scientists and enter the world of politics?" Siferra asked. "I don't like that. This isn't our job at all. I vote for turning our material over to the government, and letting them-"

"The government!" Beenay snorted.

"Beenay's right," said Sheerin. "I know what government people are like. They'll form a committee, and issue a report- eventually-and file the report away, and then later on they'll form another committee to dig out whatever it ~was that the first committee discovered, and then take a vote, and -No, we don't have the time for all that. It's our duty to speak out ourselves. I know at first hand what Darkness does to people's minds. Athor and Beenay, you have mathematical proof that Darkness is coming soon. You, Siferra, you've seen what Darkness has done to past civilizations."

"But do we dare seek out the Apostles?" Beenay asked. "Won't we be endangering our own reputations for scientific responsibility if we have anything to do with them?"

"Good point," Siferra said. "We have to keep away from them!"

Athor frowned. "Perhaps you're right. It may have been naive of me to suggest that we could form any sort of working partnership with those people. I withdraw the suggestion."

"Wait," said Beenay. "I have a friend-you know him, Sheerin, he's the newspaperman Theremon-who's already been in touch with some high official of the Apostles. He might be able to arrange a secret meeting between Athor and that High Apostle. You could sound the Apostles out, sir, and see if they know anything worth our having-just by way of obtaining even more confirming evidence for ourselves-and we can always deny the meeting took place, if it turns out they don't."

"That's a possibility," Athor said. "Distasteful as it would be, I'd be willing to meet with them. -I assume, then, that none of you has any fundamental dispute now with my basic suggestion? You agree with me that it's essential that we four take some action in response to what we've discovered?"

"I do now," Beenay said, glancing at Sheerin. "I still intend to survive the Darkness myself. But everything that's been said here today leads me to realize that a lot of others won't. Nor will civilization itself-unless we do something."

Athor nodded. "Very well. Talk to your friend Theremon. Cautiously, though. You know how I feel about the press. Journalists aren't much more to my liking than the Apostles are.

But very carefully let your Theremon understand that I'd like to meet privately with this Apostle he knows."

"I will, sir."

"You, Sheerin: get together all the literature you can find concerning the effects of exposure to prolonged Darkness, and let me have it."

"No problem there, Doctor."

"And you, Siferra-may I have a report, suitable for the understanding of laymen, on your Thombo excavation? With every scrap of evidence you are able to supply concerning this repetitive-conflagration business."

"Some of it's not ready yet, Dr. Athor. Material I didn't discuss today."

Athor's brows furrowed. "What do you mean?"

"Inscribed clay tablets," she said. "Found in the third and fifth levels from the top. Dr. Mudrin is attempting the very difficult task of translating them. His preliminary opinion is that they're some kind of priestly warning of the coming fire."

"The first edition of the Book of Revelations!" Beenay shouted.

"Well, yes, perhaps that is what they are," Siferra said, laughing without much sign of amusement. "At any rate, I hope to have the tablet texts soon. And then I'll get all the material together for you, Dr. Athor."

"Good," Athor said. "We'll need everything we can get. This is going to be the job of our lives." He glanced once more at each of the others in turn. "One important thing to remember, though: my willingness to engage in an approach to the Apostles does not mean that I intend in any way to provide a blanket of respectability for them. I merely hope to find out what they have that will help us to convince the world of what's about to happen, period. Otherwise I'll do what I can to distance myself from them. I want no mysticism involved here. I don't believe a shred of their mumbo-jumbo-I simply want to know how they've arrived at their conclusions of catastrophe. And I want the rest of you to be similarly on your guard in any dealings with them. Understood?"

"This is all like a dream," Beenay said softly.

"A very bad one," said Athor. "Every atom in my soul cries out that this isn't happening, that it's utter fantasy, that the world will keep right on going past next Theptar nineteenth without any harm coming to it. Unfortunately, the figures tell the story." He looked out the window. Onos now was gone from the sky, and Dovim was only a dot against the horizon. Twilight had descended, and the only real illumination that was visible was the ghostly, uncomforting light of Patru and Trey. "There's no longer any way for us to doubt it. Darkness will come. Perhaps the Stars, whatever they may be, really will shine forth. Fires will blaze. The end of the world as we know it is at hand. The end of the world!"

"You'd better be careful," Beenay said. He was beginning to feel tense. Evening was coming on-the evening of the eclipse, so long awaited by him with fear and trembling. "Athor's furious with you, Theremon. I can't believe you came here now. You know you're not supposed to be anywhere on the premises. Especially not this evening, of all times to show up. You ought to be able to understand that, when you consider the sort of things you've been writing about him lately-"

The journalist chuckled. "I told you. I can calm him down."

"Don't be too sure of that, Theremon. You basically called him a superannuated crackbrain in your column, remember? The old man's calm and steely most of the time, but when he's pushed too far he's got an amazing temper."

Theremon said, with a shrug, "Look, Beenay, before I was a big-shot columnist I was a kid reporter who specialized in doing all sorts of impossible interviews, and I mean impossible. I'd come home every evening with bruises, black eyes, sometimes a broken bone or two, but I always got my story. You develop a certain degree of confidence in yourself after you've spent a few years routinely driving people out of their minds for the sake of getting a story. I'll be able to take care of Athor."

"Driving people out of their minds?" Beenay said. He glanced meaningfully toward the calendar-plate high in the wall of the corridor. In gleaming green letters it announced the date: 19 THEPTAR. The day of days, the one that had been blazing in everyone's mind, here at the Observatory, month after month. The last day of sanity that many, perhaps most, of the people of Kalgash would ever know. "Not the best choice of words this evening, wouldn't you say?"

Theremon smiled. "Maybe you're right. We'll see." He pointed toward the closed door of Athor's office. "Who's in there right now?"

"Athor, of course. And Thilanda-she's one of the astronomers. Davnit, Simbron, Hikkinan, all Observatory staffers. That's about it."

"What about Siferra? She said she'd be here."

"Well, she isn't, not yet."

A look of surprise appeared on Theremon's face. "Really? When I asked her the other day if she would opt for the Sanctuary she practically laughed in my face. She was dead set on watching the eclipse from here. I can't believe she's changed her mind. That woman isn't afraid of anything, Beenay. Well, maybe she's tidying up a few last-minute things over at her office."

"Very likely."

"And our chubby friend Sheerin? He's not here either?"

"No, not Sheerin. He's in the Sanctuary."

"Not the bravest of men, is he, our Sheerin?"

"At least he's got the good sense to admit it. Raissta's at the Sanctuary too, and Athor's wife Nyilda, and just about everybody else I know, except us few Observatory people. If you were smart you'd be there yourself, Theremon. When the Darkness gets here this evening you'll wish that you were."

"The Apostle Folimun 66 said more or less the same thing to me over a year ago, only it was his Sanctuary he was inviting me into, not yours. But I'm fully prepared to face the worst terrors the gods can throw at me, my friend. There's a story to cover this evening, and I won't be able to cover it if I'm holed up in some snug little underground hideout, will I?"

"There won't be any newspaper tomorrow for you to write that story for, Theremon~"

"You think so?" Theremon caught Beenay by the arm and drew close to him, almost nose to nose. In a low, intense tone he said, "Tell me this, Beenay. Just between friends. Do you actually and truly think that any such incredible thing as Nightfall is going to happen this evening?"