"A reasonably intelligent man should be able--" Dave began.

Ser Perth cut his words off with a sharp laugh. "Maybe a man. But who said you were a man, Dave Hanson? Can't you even understand that? You're only half human. The other half is mandrake--a plant that is related to humanity through shapes and signs by magic. We make simulacra out of mandrakes--like the manicurist in the barber shop. And sometimes we use a mandrake root to capture the essence of a real man, in which case he's a mandrake-man, like you. Human? No. But a very good imitation, I must admit."

Dave turned from Ser Perth toward Nema, but her head was bent over the cords she was weaving, and she avoided his eyes. He remembered now that she'd called him a mandrake-man before, in a tone of pity. He looked down at his body, sick in his mind. Vague bits of fairy tales came back to him, suggesting horrible things about mandrake creatures--zombie-like things, only outwardly human.

Sather Karf seemed amused as he looked at Ser Perth. Then the old man dropped his eyes toward Dave, and there was a brief look of pity in them. "No matter, Dave Hanson," he said. "You were human, and by the power of your true name, you are still the same Dave Hanson. We have given you life as precious as your other life. Pay us for that with your service, and that new life will be truly precious. We need your services."

"What do you want?" Dave asked. He couldn't fully believe what he'd heard, but there had been too many strange things to let him disbelieve, either. If they had made him a mandrake-man, then by what little he could remember and guess, they could make him obey them.

"Look out the window--at the sky," Sather Karf ordered.

Dave looked. The sunset colors were still vivid. He stepped forward and peered through the crystalline gla.s.s. Before him was a city, bathed in orange and red, towering like the skyline of a dozen cities he had seen--and yet; not like any. The buildings were huge and many-windowed.

But some were straight and tall, some were squat and fairy-colored and others blossomed from thin stalks into impossibly bulbous, minareted domes, like long-stemmed tulips reproduced in stone. Haroun-al-Rashid might have accepted the city, but Mayor Wagner could never have believed in it.

"Look at the sky," the old man suggested again, and there was no mockery in his voice now.

Dave looked up obediently.

The sunset colors were not sunset. The sun was bright and blinding overhead, surrounded by reddish clouds, glaring down on the fairy city.

The sky was--blotchy. It was daylight, but through the clouds bright stars were shining. A corner of the horizon was winter blue; a whole sweep of it was dead, featureless black. It was a nightmare sky, an impossible sky. Dave's eyes bulged as he looked at it.

He turned back to Sather Karf. "What--what's the matter with it?"

"What indeed?" There was bitterness and fear in the old man's voice. In the corner of the room, Nema looked up for a moment, and there was fear and worry in her eyes before she looked back to her weaving of endless knots. Sather Karf sighed in weariness. "If I knew what was happening to the sky, would I be dredging the muck of Duality for the likes of you, Dave Hanson!"

He stood up, wearily but with a certain ease and grace that belied his age, looking down at Dave. There was stern command in his words, but a hint of pleading in his expression.

"The sky's falling, Dave Hanson. Your task is to put it together again.

See that you do not fail us!"

He waved dismissal and Ser Perth led Dave and Nema out.

IV

The corridor down which they moved this time was one that might have been familiar even in Dave's Chicago. There was the sound of typewriters from behind the doors, and the floor was covered with composition tile, instead of the too-lush carpets. He began to relax a little until he came to two attendants busily waxing the floor. One held the other by the ankles and pushed the creature's hairy face back and forth, while its hands spread the wax ahead of it. The results were excellent, but Dave found it hard to appreciate.

Ser Perth shrugged slightly. "They're only mandrakes," he explained. He threw open the door of one of the offices and led them through an outer room toward an inner chamber, equipped with comfortable chairs and a desk. "Sit down, Dave Hanson. I'll fill you in on anything you need to know before you're a.s.signed. Now--the Sather Karf told you what you were to do, of course, but--"

"Wait a minute," Dave suggested. "I don't remember being told any such thing."

Ser Perth looked at Nema, who nodded. "He distinctly said you were to repair the sky. I've got it down in my notes if you want to see them."

She extended the woven cords.

"Never mind," Ser Perth said. He twiddled with his mustache. "I'll recap a little. Dave Hanson, as you have seen, the sky is falling and must be repaired. You are our best hope. We know that from a prophecy, and it is confirmed by the fact that the fanatics of the Egg have tried several times to kill you. They failed, though one effort was close enough, but their attempts would not have been made at all if they had not been convinced through their arts that you can succeed with the sky."

Dave shook his head. "It's nice to know you trust me!"

"Knowing that you _can_ succeed," the other went on smoothly, "we know that you will. It is my unpleasant duty to point out to you the things that will happen if you fail. I say nothing of the fact that you owe us your life; that may be a small enough gift, and one quickly withdrawn. I say only that you have no escape from us. We have your name, and the true symbol is the thing, as you should know. We also have cuttings from your hair and your beard; we have the parings of your nails, five cubic centimeters of your spinal fluid and a sc.r.a.ping from your liver. We have your body through those, nor can you take it out of our reach. Your name gives us your soul." He looked at Hanson piercingly. "Shall I tell you what it would be like for your soul to live in the muck of a swamp in a mandrake root?"

Dave shook his head. "I guess not. I--look, Ser Perth. I don't know what you're talking about. How can I go along with you when I'm in the dark?

Start at the beginning, will you? I was killed; all right, if you say I was, I was. You brought me to life again with a mandrake root and spells; you can do anything you want with me. I admit it; right now, I'll admit anything you want me to, because you know what's going on and I don't. But what's all this business of the sky falling? If it is and can be falling, what's the difference? If there is a difference, why should I be able to do anything about it?"

"Ignorance!" Ser Perth murmured to himself. He sighed heavily. "Always ignorance. Well, then, listen." He sat down on the corner of the desk and took out a cigarette. At least it looked like a cigarette. He snapped his fingers and lighted it from a little flame that sprang up, blowing clouds of bright green smoke from his mouth. The smoke hung lazily, drifting into vague patterns and then began to coalesce into a green houri without costume. He swatted at it negligently.

"Dratted sylphs. There's no controlling the elementals properly any more." He didn't seem too displeased, however, as he watched the thing dance off. Then he sobered.

"In your world, Dave Hanson, you were versed in the engineering arts--you more than most. That you should be so ignorant, though you were considered brilliant is a sad commentary on your world. But no matter. Perhaps you can at least learn quickly still. Even you must have had some idea of the composition of the sky?"

Dave frowned as he tried to answer. "Well, I suppose the atmosphere is oxygen and nitrogen, mostly; then there's the ionosphere and the ozone layer. As I remember, the color of the sky is due to the scattering of light--light rays being diffracted in the air."

"Beyond the air," Ser Perth said impatiently. "The sky itself!"

"Oh--s.p.a.ce. We were just getting out there with manned ships. Mostly vacuum, of course. Of course, we're still in the solar atmosphere, even there, with the Van Allen belts and such things. Then there are the stars, like our sun, but much more distant. The planets and the moon--"

"Ignorance was bad enough," Ser Perth interrupted in amazement. He stared at Dave, shaking his head in disgust. "You obviously come from a culture of even more superst.i.tion than ignorance. Dave Hanson, the sky is no such thing. Put aside the myths you heard as a child. The sky is a solid sphere that surrounds Earth. The stars are no more like the sun than the glow of my cigarette is like a forest fire. They are lights on the inside of the sphere, moving in patterns of the Star Art, nearer to us than the hot lands to the south."

"Fort," Dave said. "Charles Fort said that in a book."

Ser Perth shrugged. "Then why make me say it again? This Fort was right.

At least one intelligent man lived in your world, I'm pleased to know.

The sky is a dome holding the sun, the stars and the wandering planets.

The problem is that the dome is cracking like a great, smashed eggsh.e.l.l."

"What's beyond the dome?"

Ser Perth shuddered slightly. "My greatest wish is that I die before I learn. In your world, had you discovered that there were such things as elements? That is, basic substances which in combination produce--"

"Of course," Dave interrupted.

"Good. Then of the four elements--" Dave gulped, but kept silent, "--of the four elements the universe is built. Some things are composed of a single element; some of two, some of three. The proportions vary and the humors and spirits change but all things are composed of the elements.

And only the sky is composed of all four elements--of earth, of water, of fire and of air--in equal proportions. One part each, lending each its own essential quality to the mixture, so that the sky is solid as earth, radiant as fire, formless as water, insubstantial as air. And the sky is cracking and falling, as you have seen for yourself. The effects are already being felt. Gamma radiation is flooding through the gaps; the quick-breeding viruses are mutating through half the world, faster than the Medical Art can control them, so that millions of us are sneezing and choking--and dying, too, for lack of antibiotics and proper care. Air travel is a perilous thing; just today, a stratosphere roc crashed head-on into a fragment of the sky and was killed with all its pa.s.sengers. Worst of all, the Science of Magic suffers. Because the stars are fixed on the dome of the sky. With the crumbling of that dome, the course of the stars has been corrupted. It's pitiful magic that can be worked without regard to the conjunctions of the planets; but it is all the magic that is left to us. When Mars trines Neptune, the Medical Art is weak; even while we were conjuring you, the trine occurred. It almost cost your life. And it should not have occurred for another seven days."

There was silence, while Ser Perth let Dave consider it. But it was too much to accept at once, and Dave's mind was a treadmill. He'd agreed to admit anything, but some of this was such complete nonsense that his mind rejected it automatically. Yet he was sure Ser Perth was serious; there was no humor on the face of the prissy thin-mustached man before him. Nor had the Sather Karf considered it a joke, he was sure. He had a sudden vision of the latter strangling two men from a distance of thirty feet without touching them. That couldn't happen in a sane world, either.

Dave asked weakly, "Could I have a drink?"

"With a sylph around?" Ser Perth grimaced. "You wouldn't have a chance.

Now, is all clear to you, Dave Hanson?"

"Sure. Except for one thing. What am I supposed to do?"

"Repair our sky. It should not be too difficult for a man of your reputation. You built a wall across a continent high and strong enough to change the air currents and affect all your weather--and that in the coldest, meanest country in your world. You come down to us as one of the greatest engineers of history, Dave Hanson, so great that your fame has penetrated even to our world, through the viewing pools of our wisest historians. There is a shrine and monument in your world. 'Dave Hanson, to whom nothing was impossible.' Well, we have a nearly impossible task: a task of engineering and building. If our Science of Magic could be relied upon--but it cannot; it never can be, until the sky is fixed. We have the word of history: no task is impossible to Dave Hanson."

Dave looked at the smug face and a slow grin crept over his own, in spite of himself. "Ser Perth, I'm afraid you've made a slight mistake."