"We don't make mistakes in such matters. You're Dave Hanson," Ser Perth said flatly. "Of all the powers of the Science, the greatest lies in the true name. We evoked you by the name of Dave Hanson. You _are_ Dave Hanson, therefore."

"Don't try to deceive us," Nema suggested. Her voice was troubled. "Pray rather that we never have reason to doubt you. Otherwise the wisest of the Satheri would spend their remaining time in planning something unthinkable for you."

Ser Perth nodded vigorous a.s.sent. Then he motioned to the office. "Nema will show you to your quarters later. Use this until you leave. I have to report back."

Dave stared after him until he was gone, and then around at the office.

He went to the window and stared upwards at the crazy patchwork of the sky. For all he knew, in such a sky there might be cracks. In fact, as he looked, he could make out a rift, and beyond that a ... hole ... a small patch where there was no color, and yet the sky there was not black. There were no stars there, though points of light were cl.u.s.tered around the edges, apparently retreating.

All he had to do was to repair the sky. Shades of Chicken Little!

Maybe to David Arnold Hanson, the famed engineer, no task was impossible. But quite a few things were impossible to that engineer's obscure and unimportant nephew, the computer technician and generally undistinguished man who had been christened Dave. They'd gotten the right man for the name, all right. But the wrong man for the job.

Dave Hanson could repair anything that contained electrical circuits or ran on tiny jeweled bearings, but he could handle almost nothing else.

It wasn't stupidity or incapacity to learn, but simply that he had never been subjected to the discipline of construction engineering. Even on the project, while working with his uncle, he had seen little of what went on, and hadn't really understood that, except when it produced data that he could feed into his computer. He couldn't drive a nail in the wall to hang a picture or patch a hole in the plaster.

But it seemed that he'd better put on a good show of trying if he wanted to continue enjoying good health.

"I suppose you've got a sample of the sky that's fallen?" he asked Nema.

"And what the heck are you doing here, anyhow? I thought you were a nurse."

She frowned at him, but went to a corner where a small ball of some clear crystalline substance stood. She muttered into it, while a surly face stared out. Then she turned back to him, nodding. "They are sending some of the sky to you. As to my being a nurse, of course I am. All student magicians take up the Medical Art for a time. Surely one so skilled can also be a secretary, even to the great Dave Hanson? As to why I'm here--" She dropped her eyes, frowning, while a touch of added color reached her cheeks. "In the sleep spell I used, I invoked that you should be well and true. But I'm only a bachelor in magic, not even a master, and I slipped. I phrased it that I wanted you well and true.

Hence, well and truly do I want you."

"Huh?" He stared at her, watching the blush deepen. "You mean--?"

"Take care! First you should know that I am proscribed as a duly registered virgin. And in this time of need, the magic of my blood must not be profaned." She twisted sidewise, and then turned toward the door, avoiding him. Before she reached it, the door opened to show a dull clod, entirely naked, holding up a heavy weight of nothing.

"Your sample of sky," she said as the clod labored over to the desk and dropped nothing with a dull clank. The desk top dented slightly.

Dave could clearly see that nothing was on the desk. But if nothing was a vacuum, this was an extremely hard and heavy one. It seemed to be about twelve inches on a side, in its rough shape, and must have weighed two hundred pounds. He tapped it, and it rang. Inside it, a tiny point of light danced frantically back and forth.

"A star," she said sadly.

"I'm going to need some place to experiment with this," he suggested. He expected to be sent to the deepest, dankest cave of all the world as a laboratory, and to find it equipped with pedigreed bats, dried unicorn horns and whole rows of alembics that he couldn't use.

Nema smiled brightly. "Of course. We've already prepared a construction camp for you. You'll find most of the tools you used in your world waiting there and all the engineers we could get or make for you."

He'd been considering stalling while he demanded exactly such things. He was reasonably sure by now that they had no transistors, signal generators, frequency meters or whatever else he could demand. He could make quite an issue out of the need to determine the characteristic impedance of their sky. That might even be interesting, at that; would it be anywhere near 300 ohms here? But it seemed that stalling wasn't going to work. They'd given him what they expected him to need, and he'd have to be careful to need only what they expected, or they might just decide he wasn't Dave Hanson.

"I can't work on this stuff here," he said.

"Then why didn't you say so?" she asked sharply. She let out a cry and a raven came flying in. She whispered something to it, frowned, and then ordered it off. "There's no surface transportation available, and all the local rocs are in use. Well, we'll have to make do with what we have."

She darted for the outer office, rummaged in a cabinet, and came back with a medium-sized rug of worn but gaudy design. Bad imitation Sarouk, Dave guessed. She tossed it onto the largest cleared s.p.a.ce, gobbled some outlandish noises, and dropped onto it, squatting near one end.

Behind her, the dull clod picked up the sample of sky and fell to his face on the rug. At her vehement signal, Dave squatted down beside her, not daring to believe what he was beginning to guess.

The carpet lifted uncertainly. It seemed to protest at the unbalanced weight of the sky piece. She made the sounds again, and it rose reluctantly, curling up at the front, like a crazy toboggan. It moved slowly, but with increasing speed, sailed out of the office through the window and began gaining alt.i.tude. They went soaring over the city at about thirty miles an hour, heading toward what seemed to be barren land beyond. "Sometimes they fail now," she told him. "But so far, only if the words are improperly p.r.o.nounced."

He gulped and looked gingerly over at the city below. As he did, she gasped. He heard a great tearing sound of thunder. In the sky, a small hole appeared. There was a scream of displaced air, and something went zipping downwards in front of them, setting up a wind that bounced the carpet about crazily. Dave glanced over the edge again to see one of the tall buildings crumple under the impact. The three top stories were ripped to shreds. Then the whole building began to change. It slowly blossomed into a huge cloud of pink gas that rifted away, to show people and objects dropping like stones to the ground below. Nema sighed and turned her eyes away.

"But--it's ridiculous!" Dave protested. "We heard the rip and less than five seconds later, that piece fell. If your sky is even twenty miles above us, it would take longer than that to fall."

"It's a thousand miles up," she told him. "And sky has no inertia until it is contaminated by contact with the ground. It took longer than usual for that piece to fall." She sighed. "It gets worse. Look at the signs. That break has disturbed the planets. We're moving retrograde, back to our previous position, out of Sagittarius! Now we'll go back to the character we had before--and just when I was getting used to the change."

He jerked his eyes off the raw patch of emptiness in the sky, where a few stars seemed to be vanishing. "Your character? Isn't anything stable here?"

"Of course not. Naturally, in each House we have a differing of character, as does the world itself. Why else should astrology be the greatest of the sciences?"

It was a nice world, he decided. And yet the new factor explained some things. He'd been vaguely worried about the apparent change in Ser Perth, who'd turned from a serious and helpful doctor into a supercilious, high-handed fop. But--what about his recovery, if that was supposed to be determined by the signs of the zodiac?

He had no time to ask. The carpet bucked, and the girl began speaking to it urgently. It wavered, then righted itself, to begin sliding downwards.

"There is a ring of protection around your camp," Nema explained. "It is set to make entry impossible to one who does not have the words or who is unfriendly. The carpet could not go through that, anyway. The ring negates all other magic trying to pa.s.s it. And of course we have basilisks mounted on posts around the grounds. They're trained to hood their eyes, except when they sense anyone trying to enter who should not. You can't be turned to stone looking at one, you know--only by having one look at you."

"You're cheering me up no end," he a.s.sured her.

She smiled pleasantly and began setting the carpet down. Below, he could see a camp that looked much like the camps he had seen in the same movies from which all his clothes had been copied. There were well laid-out rows of sheds, beautiful lines of construction equipment and everything in order, as it could never be in a real camp. As he began walking with the girl toward a huge tent that should have belonged to a circus, he could see other discrepancies. The tractors were designed for work in mud flats and the haulers had the narrow wheels used on rocky ground. Nothing seemed quite as it should be. He spotted a big generator working busily--and then saw a gang of about fifty men, or mandrakes, turning a big capstan that kept it going. Here and there were neat racks of miscellaneous tools. Some were museum pieces. There was even a gandy cart, though no rails for it to run on.

They were almost at the main tent when a crow flew down and yelled something in Nema's ear. She scowled, and nodded. "I'm needed back," she said. "Most of the men here--" She pointed to the gangs that moved about busily doing nothing, all in costumes similar to his, except for the boots and hat. "They're mandrakes, conjured into existence, but without souls. The engineers we have are s.n.a.t.c.hed from Duality just after dying and revived here while their brains still retain their knowledge. They have no true souls either, of course, but they don't know it. Ah. The short man there--he's Garm. Sersa Garm, an apprentice to Ser Perth. He's to be your foreman, and he's real."

She headed back to the outskirts, then turned to shout back. "Sather Karf says you may have ten days to fix the sky," she called. Her hand waved toward him in friendly good-bye. "Don't worry, Dave Hanson. I have faith in you."

Then she was running toward her reluctant carpet.

Dave stared up at the mottled dome above him and at the dull clod--certainly a mandrake--who was still carrying the sample. With all this preparation and a time limit, he couldn't even afford to stall.

He'd never fully understood why some plastics melted and others turned hard when heated, but he had to find what was wrong with the dome above and how to fix it. And maybe the time limit could be stretched a little, once he came up with the answer. Maybe. He'd worry about that after he worried about the first steps.

Sersa Garm proved to be a glum, fat young man, overly aware of his importance in training for serhood. He led Dave through the big tent, taking pride in the large drafting section--under the obvious belief that it was used for designing spells. Maybe it could have been useful for that if there had been a single man who knew anything about draftsmanship. There were four engineers, supposedly. One, who had died falling off a bridge while drunk, was curing himself of the shock by remaining dead drunk. One had been a chemical engineer specializing in making yeast and dried soya meal into breakfast cereals. Another knew all about dredging ca.n.a.ls and the last one was an electronics engineer--a field in which Dave was far more competent.

He dismissed them. Whatever had been done to them--or perhaps the absence of a true soul, whatever that was--left them rigidly bound to their past ideas and totally incapable of doing more than following orders by routine now. Even Sersa Garm was more useful.

That young man could offer little information, however. The sky, he explained pompously, was a great mystery that only an adept might communicate to another. He meant that he didn't know about it, Dave gathered. Everything, it turned out, was either a mystery or a rumor.

He also had a habit of sucking his thumb when pressed too hard for details.

"But you must have heard some guesses about what started the cracks in the sky?" Dave suggested.

"Oh, indeed, that is common knowledge," Sersa Garm admitted. He changed thumbs while he considered. "'Twas an experiment most n.o.ble, but through mischance going sadly awry. A great Sather made the sun remain in one place too long, and the heat became too great. It was like the Cla.s.sic experiment--"

"How hot is your sun?"

There was a long pause. Then Sather Germ shrugged. "'Tis a great mystery. Suffice to say it has no true heat, but does send forth an activating principle against the phlogiston layer, which being excited grows vengeful against the air ... but you have not the training to understand."

"Okay, so they didn't tell you, if they knew." Dave stared up at the sun, trying to guess. The light looked about like what he was used to, where the sky was still whole. North light still was like what a color photographer would consider 5500 Kelvin, so the sun must be pretty hot.

Hot enough to melt anything he knew about. "What's the melting point of this sky material?"

He never did manage to make Sather Garm understand what a melting point was. But he found that one of the solutions tried had been the bleeding of eleven certified virgins for seven days. When the blood was mixed with dragonfeathers and frogsdown and melded with a genuine philosopher's stone, they had used it to ink in the right path of the planets of a diagram. It had failed. The sky had cracked and a piece had fallen into the vessel of blood, killing a Sather who was less than two thousand years old.

"Two thousand?" Dave asked. "How old is Sather Karf?"