'I know,' replied Theremon cautiously, 'that that is the current archaeological theory. Has it been accepted as a fact?'
'Just about. In this last century it's been generally agreed upon. This cyclic character is -- or rather, was -- one of the great mysteries. We've located series of civilizations, nine of them definitely, and indications of others as well, all of which have reached heights comparable to our own, and all of which, without exception, were destroyed by fire at the very height of their culture.
'And no one could tell why. All centers of culture were thoroughly gutted by fire, with nothing left behind to give a hint as to the cause.'
Theremon was following closely. 'Wasn't there a Stone Age, too?'
'Probably, but as yet practically nothing is known of it, except that men of that age were little more than rather intelligent apes. We can forget about that.'
'I see. Go on!'
There have been explanations of these recurrent catastrophes, all of a more or less fantastic nature. Some say that there are periodic rains of fire; some that Lagash passes through a sun every so often; some even wilder things. But there is one theory, quite different from all of these, that has been handed down over a period of centuries.'
'I know. You mean this myth of the "Stars" that the Cultists have in their Book of Revelations.'
'Exactly,' rejoined Sheerin with satisfaction. 'The Cultists said that every two thousand and fifty years Lagash entered a huge cave, so that all the suns disappeared, and there came total darkness all over the world! And then, they say, things called Stars appeared, which robbed men of their souls and left them unreasoning brutes, so that they destroyed the civilization they themselves had built up. Of course they mix all this up with a lot of religio-mystic notions, but that's the central idea.'
There was a short pause in which Sheerin drew a long breath. 'And now we come to the Theory of Universal Gravitation.' He pronounced the phrase so that the capital letters sounded -- and at that point Aton turned from the window, snorted loudly, and stalked out of the room.
The two stared after him, and Theremon said, 'What's wrong?'
'Nothing in particular,' replied Sheerin. 'Two of the men were due several hours ago and haven't shown up yet. He's terrifically short-handed, of course, because all but the really essential men have gone to the Hideout.'
'You don't think the two deserted, do you?'
'Who? Faro and Yimot? Of course not. Still, if they're not back within the hour, things would be a little sticky.' He got to his feet suddenly, and his eyes twinkled. 'Anyway, as long as Aton is gone -- '
Tiptoeing to the nearest window, he squatted, and from the low window box beneath withdrew a bottle of red liquid that gurgled suggestively when he shook it.
'I thought Aton didn't know about this,' he remarked as he trotted back to the table. 'Here! We've only got one glass so, as the guest, you can have it. I'll keep the bottle.'
And he filled the tiny cup with judicious care. Theremon rose to protest, but Sheerin eyed him sternly.
'Respect your elders, young man.'
The newsman seated himself with a look of anguish on his face. 'Go ahead, then, you old villain.'
The psychologist's Adam's apple wobbled as the bottle upended, and then, with a satisfied grunt and a smack of the lips, he began again. 'But what do you know about gravitation?'
'Nothing, except that it is a very recent development, not too well established, and that the math is so hard that only twelve men in Lagash are supposed to understand it.'
'Tcha! Nonsense! Baloney! I can give you all the essential math in a sentence. The Law of Universal Gravitation states that there exists a cohesive force among all bodies of the universe, such that the amount of this force between any two given bodies is proportional to the product of their masses divided by the square of the distance between them.'
'Is that all?'
'That's enough! It took four hundred years to develop it.'
'Why that long? It sounded simple enough, the way you said it.'
'Because great laws are not divined by flashes of inspiration, whatever you may think. It usually takes the combined work of a world full of scientists over a period of centuries. After Genovi 4I discovered that Lagash rotated about the sun Alpha rather than vice versa -- and that was four hundred years ago -- astronomers have been working. The complex motions of the six suns were recorded and analyzed and unwoven. Theory after theory was advanced and checked and counterchecked and modified and abandoned and revived and converted to something else. It was a devil of a job.'
Theremon nodded thoughtfully and held out his glass for more liquor. Sheerin grudgingly allowed a few ruby drops to leave the bottle.
'It was twenty years ago,' he continued after remoistening his own throat, 'that it was finally demonstrated that the Law of Universal Gravitation accounted exactly for the orbital motions of the six suns. It was a great triumph.'
Sheerin stood up and walked to the window, still clutching his bottle. 'And now we're getting to the point. In the last decade, the motions of Lagash about Alpha were computed according to gravity, and it did not account for the orbit observed; not even when all perturbations due to the other suns were included. Either the law was invalid, or there was another, as yet unknown, factor involved.'
Theremon joined Sheerin at the window and gazed out past the wooded slopes to where the spires of Saro City gleamed bloodily on the horizon. The newsman felt the tension of uncertainty grow within him as he cast a short glance at Beta. It glowered redly at zenith, dwarfed and evil.
'Go ahead, sir,' he said softly.
Sheerin replied, 'Astronomers stumbled about for year, each proposed theory more untenable than the one before -- until Aton had the inspiration of calling in the Cult. The head of the Cult, Sor 5, had access to certain data that simplified the problem considerably. Aton set to work on a new track.
'What if there were another nonluminous planetary body such as Lagash? If there were, you know, it would shine only by reflected light, and if it were composed of bluish rock, as Lagash itself largely is, then, in the redness of the sky, the eternal blaze of the suns would make it invisible -- drown it out completely.'
Theremon whistled. 'What a screwy idea!'
'You think that's screwy? Listen to this: Suppose this body rotated about Lagash at such a distance and in such an orbit and had such a mass that its attention would exactly account for the deviations of Lagash's orbit from theory -- do you know what would happen?'
The columnist shook his head.
'Well, sometimes this body would get in the way of a sun.' And Sheerin emptied what remained in the bottle at a draft.
'And it does, I suppose,' said Theremon flatly.
'Yes! But only one sun lies in its plane of revolution.' He jerked a thumb at the shrunken sun above. 'Beta! And it has been shown that the eclipse will occur only when the arrangement of the suns is such that Beta is alone in its hemisphere and at maximum distance, at which time the moon is invariably at minimum distance. The eclipse that results, with the moon seven times the apparent diameter of Beta, covers all of Lagash and lasts well over half a day, so that no spot on the planet escapes the effects. That eclipse comes once every two thousand and forty-nine years.'
Theremon's face was drawn into an expressionless mask.
'And that's my story?'
The psychologist nodded. 'That's all of it. First the eclipse -- which will start in three quarters of an hour -- then universal Darkness and, maybe, these mysterious Stars -- then madness, and end of the cycle.'
He brooded. 'We had two months' leeway -- we at the Observatory -- and that wasn't enough time to persuade Lagash of the danger. Two centuries might not have been enough. But our records are at the Hideout, and today we photograph the eclipse. The next cycle will start off with the truth, and when the next eclipse comes, mankind will at last be ready for it. Come to think of it, that's part of your story too.'
A thin wind ruffled the curtains at the window as Theremon opened it and leaned out. It played coldly with his hair as he stared at the crimson sunlight on his hand. Then he turned in sudden rebellion.
'What is there in Darkness to drive me mad?'
Sheerin smiled to himself as he spun the empty liquor bottle with abstracted motions of his hand. 'Have you ever experienced Darkness, young man?'
The newsman leaned against the wall 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 no light. Like in caves.' ,
'Have you ever been in a cave?'
'In a cave! Of course not!'