In the hours that followed, Dave's vague plans changed a dozen times as he found each idea unworkable. His emotional balance was also erratic—though that was natural, since the stars were completely berserk in what was left of the sky. He seemed to fluctuate between bitter sureness of doom and a stupidly optimistic belief that something could be done to avert that doom. But whatever his mood, he went on working and scheming furiously. Maybe it was the desperate need to keep himself occupied that drove him, or perhaps it was the pleading he saw in the eyes around him. In the end, determination conquered his pessimism.

Somewhere in the combination of the science he had learned in his own world and the technique of magic that applied here there had to be an answer—or a means to hold back the end of the world until an answer could be found.

The biggest problem was the number of factors with which he had to deal. There were seven planets and the sun, and three thousand fixed stars. All had to be ordered in their courses, and the sky had to be complete in his calculations.

He had learned his trade where the answer was always to add one more circuit in increasing complexity. Now he had to think of the simplest possible similarity computer. Electronics was out, obviously. He tried to design a set of cams, like the tide machine, to make multiple tracings on paper similar to a continuous horoscope, but finally gave it up. They couldn't build the parts, even if there had been time.

He had to depend on what was available, since magic couldn't produce any needed device and since the people here had depended on magic too long to develop the other necessary skills. When only the broadest powers of magic remained, they were hopeless. Names were still potent, resonance worked within its limits, and the general principles of similarity still applied; but those were not enough for them. They depended too heavily on the second great principle of contagion, and that seemed to be wrapped up with some kind of association through the signs and houses and the courses of the planets.

He found himself thinking in circles of worry and pulled himself back to his problem. Normally, a computer was designed for flexibility and to handle varying conditions. This one could be designed to handle only one set of factors. It had to duplicate the courses of the objects in their sky and simulate the general behavior of the dome. It was not necessary to allow for all theoretical courses, but only for the normal orbits.

And finally he realized that he was thinking of a model—the one thing which is functionally the perfect analogue.

It brought him back to magic again. Make a doll like a man and stick pins in it—and the man dies. Make a model of the universe within the sky, and any changes in that should change reality. The symbol was the thing, and a model was obviously a symbol.

He began trying to plan a model with three thousand stars in their orbits, trying to find some simple way of moving them. The others watched in fascination. They apparently felt that the diagrams he was drawing were some kind of scientific spell. Ser Perth was closer than the others, studying the marks he made. The man suddenly pointed to his computations.

"Over and over I find the figure seven and the figure three thousand. I assume that the seven represents the planets. But what is the other figure?"

"The stars," Hanson told him impatiently.

Ser Perth shook his head. "That is wrong. There were only two thousand seven hundred and eighty-one before the beginnings of our trouble."

"And I suppose you've got the exact orbits of every one?" Hanson asked. He couldn't see that the difference was going to help much.

"Naturally. They are fixed stars, which means they move with the sky. Otherwise, why call them fixed stars? Only the sun and the planets move through the sky. The stars move with the sky over the world as a unity."

Dave grunted at his own stupidity. That really simplified things, since it meant only one control for all of them and the sky itself. But designing a machine to handle the planets and the sun, while a lot simpler, was still a complex problem. With time, it would have been easy enough, but there was no time for trial and error.

He ripped up his plans and began a new set. He'd need a glass sphere with dots on it for the stars, and some kind of levers to move the planets and sun. It would be something like the orreries he'd seen used for demonstrations of planetary movement.

Ser Perth came over again, staring down at the sketch. He drowned in doubt. "Why waste time drawing such engines? If you want a model to determine how the orbits should be, we have the finest orrery ever built here in the camp. We brought it with us when we moved, since it would be needed to determine how the sky should be repaired and to bring the time and the positions into congruence. Wait!"

He dashed off, calling two of the mandrakes after him. In a few minutes, they staggered back under a bulky affair in a protective plastic case. Ser Perth stripped off the case to reveal the orrery to Hanson.

It was a beautiful piece of workmanship. There was an enormous sphere of thin crystal to represent the sky. Precious gems showed the stars, affixed to the dome. The whole was nearly eight feet in diameter. Inside the crystal, Hanson could see a model of the world on jeweled-bearing supports. The planets and the sun were set on tracks around the outside, with a clockwork drive mechanism that moved them by means of stranded spiderweb cords. Power came from weights, like those used on an old-fashioned clock. It was obviously all hand work, which must make it a thing of tremendous value here.

"Sather Fareth spent his life designing this," Ser Perth said proudly. "It is so well designed that it can show the position of all things for a thousand centuries in the past or future by turning these cranks on the control, or it will hold the proper present positions for years from its own engine."

"It's beautiful workmanship," Hanson told him. "As good as the best done on my world."

Ser Perth went away, temporarily pleased with himself, and Hanson stood staring at the model. It was as good as he'd said it was—and completely damning to all of his theories and hopes. No model he could make would equal it. But in spite of it and all its precise analogy to the universe around him, the sky was still falling in shattered bits!

Sather Karf and Bork had come over to join Hanson. They waited expectantly, but Hanson could think of nothing to do. It had already been done—and had failed. The old man dropped a hand on his shoulder. There was the weight of all his centuries on the Sather, yet a curious toughness showed through his weariness. "What is wrong with the orrery?" he asked.

"Nothing—nothing at all, damn it!" Hanson told him. "You wanted a computer—and you've got it. You can feed in data as to the hour, day, month and year, turn the cranks, and the planets there will turn to their proper position exactly as the real planets should run. You don't need to read the results off graph paper. What more could any analogue computer do? But it doesn't influence the sky."

"It was never meant to," the old man said, surprise in his voice. "Such power—"

Then he stopped, staring at Hanson while something almost like awe spread over his face. "Yet ... the prophecy and the monument were right! You have unlocked the impossible! Yet you seem to know nothing of the laws of similarity or of magic, Dave Hanson. Is that crystal similar to the sky, by association, by contagion, or by true symbolism? A part may be a symbol for the whole—or so may any designated symbol, which may influence the thing it is. If I have a hair from your head, I can model you with power over you. But not with the hair of a pig! That is no true symbol!"

"Suppose we substituted bits of the real thing for these representations?" Hanson asked.

Bork nodded. "It might work. I've heard you found the sky material could be melted, and we've got enough of that where it struck the camp. Any one of us who has studied elementary alchemy could blow a globe of it to the right size for the sky dome. And there are a few stars from which we can chip pieces enough. We can polish them and put them into the sphere where they belong. And it will be risky, but we may even be able to shape a bit of the sun stuff to represent the great orb in the sky."

"What about the planets?" Hanson was beginning to feel the depression lift. "You might get a little of Mars, since it fell near here, but that still leaves the other six."

"That long associated with a thing achieves the nature of the thing," Sather Karf intoned, as if giving a lesson to a kindergarten student. "With the right colors, metals and bits of jewels—as well as more secret symbols—we can simulate the planets. Yet they cannot be suspended above the dome, as in this orrery—they must be within the sky, as in nature."

"How about putting some iron in each and using a magnet on the control tracks to move the planets?" Hanson suggested. "Or does cold iron ruin your conjuring here?"

Sather Karf snorted in obvious disgust, but Bork only grinned. "Why should it? You must have heard peasant superstitions. Still, you'd have a problem if two tracks met, as they do. The magnets would then affect both planets alike. Better make two identical planets for each—and two suns—and put one on your track controls. Then one must follow the other, though the one remain within the sky."

Hanson nodded. He'd have to shield the cord from the sun stuff, but that could be done. He wondered idly whether the real universe was going to wind up with tracks beyond the sky on which little duplicate planets ran—just how much similarity would there be between model and reality when this was done, if it worked at all? It probably didn't matter, and it could hardly be worse than whatever the risers had run into beyond the hole in the present sky. Metaphysics was a subject with which he wasn't yet fully prepared to cope.

The model of the world inside the orrery must have been made from earthly materials already, and it was colored to depict land and sea areas. It could probably be used. At their agreement, he nodded with some satisfaction. That should save some time, at least. He stared doubtfully at the rods and bearings that supported the model world in the center of the orrery.

"What about those things? How do we hold the globe in the center of everything?"

Bork shrugged. "It seems simple enough. We'll fashion supports of more of the sky material."

"And have real rods sticking up from the poles in the real universe?" Hanson asked sarcastically.

"Why not?" Bork seemed surprised at Hanson's tone. "There have always been such columns connecting the world and the sky. What else would keep us from falling?"

Hanson swore. He might have guessed it! The only wonder was that simple rods were used instead of elephants and turtles. And the doubly-damned fools had let Menes drive millions of slaves to death to build a pyramid to the sky when there were already natural columns that could have been used!

"There remains only one step," Sather Karf decided after a moment more. "To make symbol and thing congruent, all must be invoked with the true and secret name of the universe."

Hanson suddenly remembered legends of the tetragrammaton and the tales of magic he'd read in which there was always one element lacking. "And I suppose nobody knows that or dares to use it?"

There was hurt pride of the aged face and the ring of vast authority in his voice. "Then you suppose wrong, Dave Hanson! Since this world first came out of Duality, a Sather Karf has known that mystery! Make your device and I shall not fail in the invocation!"

For the first time, Hanson discovered that the warlocks could work when they had to, however much they disliked it. And at their own specialties, they were superb technicians. Under the orders of Sather Karf, the camp sprang into frenzied but orderly activity.

They lost a few mandrakes in prying loose some of the sun material, and more in getting a small sphere of it shaped. But the remainder gave them the heat to melt the sky stuff. When it came to glass blowing, Hanson had to admit they were experts; it should have come as no surprise, after the elaborate alchemical apparatus he'd seen. Once the crystal shell was cracked out of the orrery, a fat-faced Ser came in with a long tube and began working the molten sky material, getting the feel of it. He did things Hanson knew were nearly impossible, and he did them with the calm assurance of an expert. Even when another rift in the sky appeared with a crackling of thunder, there was no faltering on his part. The sky shell and world supports were blown into shape around the world model inside the outer tracks in one continuous operation. The Ser then clipped the stuff from his tube and sealed the tiny opening smoothly with a bit of sun material on the end of a long metal wand.

"Interesting material," he commented, as if only the technical nature of the stuff had offered any problem to him.

Tiny, carefully polished chips from the stars were ready, and men began placing them delicately on the shell. They sank into it at once and began twinkling. The planets had also been prepared, and they also went into the shell, while a mate to each was attached to the tracking mechanism. The tiny sun came last. Hanson fretted as he saw it sink into the shell, sure it would begin to melt the sky material. It seemed to have no effect, however; apparently the sun was not supposed to melt the sky when it was in place—so the little sun didn't melt the shell. Once he was sure of that, he used a scrap of the sky to insulate the second little sun that would control the first sympathetically from the track. He moved the control delicately by hand, and the little sun followed dutifully.

The weights on the control mechanism were in place, Hanson noted. Someone would probably have to keep them wound from now on, unless they could devise a foolproof motor. But that was for the future. He bent to the hand cranks. Sather Karf was being called to give the exact settings for this moment, but Hanson had a rough idea of where the planets should be. He began turning the crank, just as the Sather came up.

There was a slight movement. Then the crank stuck, and there was a whirring of slipping gears! The fools who had moved the orrery must have been so careless that they'd sprung the mechanism. He bent down to study the tiny little jeweled gears. A whole gear train was out of place!

Sather Karf was also inspecting it, and the words he cried didn't sound like an invocation, though they were strange enough. He straightened, still cursing. "Fix it!"

"I'll try," Hanson agreed doubtfully. "But you'd better get the man who made this. He'll know better than I—"

"He was killed in the first cracking of the sky when a piece hit him. Fix it, Dave Hanson. You claimed to be a repairman for such devices."

Hanson bent to study it again, using a diamond lens one of the warlocks handed him. It was a useful device, having about a hundred times magnification without the need for exact focusing. He stared at the jumble of fine gears, then glanced out through the open front: of the building toward the sky. There was even less of it showing than he had remembered. Most of the great dome was empty. And now there were suggestions of ... shadows ... in the empty spots. He looked away hastily, shaken.

"I'll need some fine tools," he said.

"They were lost in moving this," Ser Perth told him. "This is the best we can do."

The jumble of tools had obviously been salvaged from the kits on the tractors in the camp. There was one fairly small pair of pliers, a small pick and assorted useless junk. He shook his head hopelessly.

"Fix it!" Sather Karf ordered again. The old man's eyes were also on the sky. "You have ten minutes, perhaps—no more."

Hanson's fingers steadied as he found bits of wire and began improvising tools to manipulate the tiny gears. The mechanism was a piece of superb craftsmanship that should have lasted for a million years, but it had never been meant to withstand the heavy shock of being dropped, as it must have been. And there was very little space inside. It should have been disassembled and put back piece by piece, but there was no time for that.

Another thunder of falling sky sounded, and the ground heaved. "Earthquakes!" Sather Karf whispered. "The end is near!"

Then a shout went up, and Hanson jerked his eyes from the gears to focus on a group of rocs that were landing at the far end of the camp. Men were springing from their backs before they stopped running—men in dull robes with elaborate masks over their faces. At the front was Malok, leader of the Sons of the Egg, brandishing his knife.

His voice carried clearly. "The egg hatches! To the orrery and smash it! That was the shadow in the pool. Destroy it before Dave Hanson can complete his magic!"

The men behind him yelled. Around Hanson, the magicians cried out in shocked fear. Then old Sather Karf was dashing out from under the cover of the building, brandishing a pole on which a drop of the sun-stuff was glowing. His voice rose into a command that rang out over the cries of the others.

Dave reached for a heavy hammer, meaning to follow. The old Sather seemed to sense it without looking back. "Fix the engine, Dave Hanson," he called.

It made sense. The others could do the fighting, but only he had training with such mechanisms. He turned back to his work, just as the warlocks began rallying behind Sather Karf, grabbing up what weapons they could find. There was no magic in this fight. Sticks, stones, hammers and knives were all that remained workable.

Dave Hanson bent over the gears, cursing. Now there was another rumble of thunder from the falling sky. The half-light from the reflected sunlight dimmed, and the ground shook violently. Another set of gears broke from the housing. Hanson caught up a bit of sun-stuff on the sharp point of the awl and brought it closer, until it burned his hands. But he had seen enough. The mechanism was ruined beyond his chance to repair it in time.

He slapped the cover shut and stuck the sun-tipped awl where it would light as much of the orrery as possible. As always, the skills of his own world had failed. To the blazes with it, then—when in magic land, magic had to do.

He thought of calling Ser Perth or Sather Karf, but there was no time for that, and they could hardly have heard him over the sounds of the desperate fight going on.

He bent to the floor, searching until he found a ball of the sky material that had been pinched off when the little opening was sealed. Further hunting gave him a few bits of dust from the star bits and some of the junk that had gone into shaping the planets. He brushed in some dirt from the ground that had been touched by the sun stuff and was still glowing faintly. He wasn't at all sure of how much he could extrapolate from what he'd read in the book on Applied Semantics, but he knew he needed a control—a symbol of the symbol, in this case. It was crude, but it might serve to represent the orrery.

He clutched it in his hand and touched it against the orrery, trying to remember the formula for the giving of a true name. He had to improvise, but he got through a rough version of it, until he came to the end: "I who created you name you—" What the deuce did he name it? "I name you Rumpelstilsken and order you to obey me when I call you by your name."

He clutched the blob of material tighter in his hand, mentally trying to shape an order that wouldn't backfire, as such orders seemed to in the childhood stories of magic he had learned. Finally his lips whispered the simplest order he could find. "Rumpelstilsken, repair yourself!"

There was a whirring and scraping inside the mechanism, and Hanson let out a yell. He got only a hasty glimpse of gears that seemed to be back on their tracks before Sather Karf was beside him, driving the cranks with desperate speed.

"We have less than a minute!" the old voice gasped.

The Sather's fingers spun on the controls. Then he straightened, moving his hands toward the orrery in passes too rapid to be seen. There was a string of obvious ritual commands in their sacred language. Then a single word rang out, a string of sounds that should have come from no human vocal chords.

There was a wrench and twist through every atom of Hanson's body. The universe seemed to cry out. Over the horizon, a great burning disc rose and leaped toward the heavens as the sun went back to its place in the sky. The big bits of sky-stuff around also jerked upwards, revealing themselves by the wind they whipped up and by the holes they ripped through the roof of the building. Hanson clutched at the scrap he had pocketed, but it showed no sign of leaving, and the tiny blob of sun-stuff remained fixed to the awl.

Through the diamond lens, Hanson could see the model of the world in the orrery changing. There were clouds apparently painted on it where no clouds had been. And there was an indication of movement in the green of the forests and the blue of the oceans, as if trees were whipping in the wind and waves lapping the shores.

When he jerked his eyes upward, all seemed serene in the sky. Sunlight shone normally on the world, and from under the roof he could see the gaudy blue of sky, complete, with the cracks in it smoothing out as he watched.

The battle outside had stopped with the rising of the sun. Half the warlocks were lying motionless, and the other half had clustered together, close to the building where Hanson and Sather Karf stood. The Sons of the Egg seemed to have suffered less, since they greatly out-numbered the others, but they were obviously more shocked by the rising of the sun and the healing of the sky.

Then Malok's voice rang out sharply. "It isn't stable yet! Destroy the machine! The egg must hatch!"

He leaped forward, brandishing his knife, while the Sons of the Egg fell in behind him. The warlocks began to close ranks, falling back to make a stand under the jutting edge of the roof, where they could protect the orrery. Bork and Ser Perth were among them, bloody but hopelessly determined.

One look at Sather Karf's expression was enough to convince Hanson that Malok had cried the truth and that their work could still be undone. And it was obvious that the warlocks could never stand the charge of the Sons. Too many of them had already been killed, and there was no time for reviving them.

Sather Karf was starting forward into the battle, but Hanson made no move to follow. He snapped the diamond lens to his eye and his fingers caught at the drop of sun-stuff on the awl. He had to hold it near the glowing bit for steadiness, and it began searing his fingers. He forced control on his muscles and plunged his hand slowly through the sky sphere, easing the glowing blob downward toward the spot on the globe he had already located with the lens. His thumb and finger moved downward delicately, with all the skill of practice at working with nearly invisibly fine wires on delicate instruments.

Then he jerked his eyes away from the model and looked out. Something glaring and hot was suspended in the air five miles away. He moved his hand carefully, steadying it on one of the planet tracks. The glowing fire in the air outside moved another mile closer—then another. And now, around it, he could see a monstrous fingertip and something that might have been miles of thumbnail.

The warlocks leaped back under the roof. The Sons of the Egg screamed and panicked. Jerking horribly, the monstrous thing moved again. For part of a second, it hovered over the empty camp. Then it was gone.

Hanson began pulling his hand out through the shell of the model, whimpering as his other hand clenched against the blob in his pocket. He had suddenly realized what horrors were possible to anyone who could use the orrery now. "Rumpelstilsken, I command you to let no hand other than mine enter and to respond to no other controls." He hoped it would offer enough protection.

His hand came free and he threw the sun-bit away with a flick of his wrist. His hand ached with the impossible task of steadiness he had set it, and his finger and thumb burned and smoked. But the wound was already healing.

In the exposed section of the camp, the Sons of the Egg were charred corpses. There was a fire starting on the roof of the building, but others had already run out to quench that. It sounded like the snuffling progress of an undine across the roof! Maybe magic was working again.

Bork turned back from the sight of his former companions. His face was sick, but he managed to grin at Hanson. "Dave Hanson, to whom nothing is impossible," he said.

Hanson had located Nema finally as she approached. He caught her hand and grabbed Bork's arm. Like his own, it was trembling with fatigue and reaction.

"Come on," he said. "Let's find some place where we can see whether it's impossible now for you to magic up a decent meal. And a drink strong enough to scare away the sylphs."

The sylph that found them wasn't scared by the Scotch, but there was enough for all of them.