Dura's belly lurched as the car jerked into motion. "Toba. Where is this City of yours?"

"At the South Pole," he said. "Downflux. As far downflux as it's possible to go."

Downflux...

Dura closed her eyes.

5.

DURA EMERGED RELUCTANTLY from sleep.

She could feel the laxness of her muscles, the slow rhythm of her heart, the rich, warm Air of the car pulsing through her lungs and capillaries. She opened her eyecups slowly and glanced around the cramped, boxy interior of the car.

The only light came from four small, clear sections of wall - windows, windows, Mixxax had called them - and the little wooden room was immersed in semi-darkness. It was a bizarre situation: to take a s.h.i.t, she'd had to open a panel and squat over a tube; when she pulled a little lever the waste had been sucked away into the Air. The cabin itself was constructed of panels of wood fixed to a framework of struts and spars. The frame surrounded her, she thought fancifully, like the rib cage of some immense, protective creature. Still half-asleep, she remembered absently her feelings of threat when first climbing into the car. Now, after less than a day, she felt only a womb-like security; it was astonishing how quickly humans could adjust. Mixxax had called them - and the little wooden room was immersed in semi-darkness. It was a bizarre situation: to take a s.h.i.t, she'd had to open a panel and squat over a tube; when she pulled a little lever the waste had been sucked away into the Air. The cabin itself was constructed of panels of wood fixed to a framework of struts and spars. The frame surrounded her, she thought fancifully, like the rib cage of some immense, protective creature. Still half-asleep, she remembered absently her feelings of threat when first climbing into the car. Now, after less than a day, she felt only a womb-like security; it was astonishing how quickly humans could adjust.

Adda's stretcher was still secured to the struts to which they had strapped it. Adda himself seemed to be asleep - or rather, unconscious. He breathed noisily, his mouth gaping and dribbling fluid; his eyes were half-open, but even his good eye was a small lake of pus which leaked slowly onto his cheek and forehead; small, harmless symbiotes covered his cheeks, lapping at the pus. Farr was curled, asleep, into a tight ball, wadded into one corner of the boxy cabin; his face was tucked into his knees and his hair waved gently as he breathed.

Mixxax sat in his comfortable-looking seat before his array of levers and gadgets. He had his back to her, his eyes focused on the journey ahead of them. As he sat in his undershorts she could see afresh how thin and bony this man from the City really was, how pale his flesh. But, at this moment, in control of his vehicle, he radiated calm and competence. It was that very calmness, the feeling of being in a controlled, secure environment - coupled with the exhaustion of the abortive hunt, the stress of Adda's injuries, the thinness of the forest Air - that had lulled Dura and Farr to fall asleep almost instantly, once the car had begun its journey.

Well, Dura was grateful for this brief interlude of peace. Soon enough the pressures of the outside world would return - the responsibilities of Adda's illness, Farr's vulnerability and need for protection, the unimaginable strangeness of the place to which they were being taken. Before long she would be looking back on this brief, secure interlude in the confining walls of the car with nostalgic affection.

Unwinding slowly, stretching to get the stiffness out of her muscles, she pushed out of her corner and glided across the small cabin to Mixxax's seat. She anch.o.r.ed herself by holding on to the back of the chair and peered past him out of his window.

Toba Mixxax gave a start, flinching away from her. Dura had to suppress a laugh at the moment of near-panic on his broad face.

"I'm sorry," he said quietly. "I thought you were asleep."

"The others still are, I think. How long was I out?"

He shrugged. "A while."

She peered out of Mixxax's window, squinting a little at the golden brightness of the Air. From the front face of the car, leather leaders led to a light wooden framework which constrained the strong young Air-pigs Mixxax called his "team." The laboring pigs were emitting green clouds of jetfart, so dense they half-obscured the animals themselves; but they were making the car sail along the vortex lines, she saw. Thin leather ropes - reins - were attached to the pierced fins of the pigs and led, through a tight membrane in the front face of the cabin, to Mixxax's hands; Mixxax held the reins almost casually, as if his control of the pigs and car was unthinking, automatic. Dura fantasized briefly about living in such a place as this magical Parz City, where the ability to direct a car like this came as naturally as Waving.

Her eye followed the tunnel of vortices far ahead of the car to the distinct point where they merged, obscuring infinity. And just beyond that red-white point at infinity she made out the dull glow of the South Pole... and perhaps, she wondered, the glow of Parz City itself.

The Crust sailed over them like an immense ceiling, detail whipping past her with disconcerting speed. The trees through which she had hunted still grew here. They dangled from the diaphanous substance of the Crust and following the Magfield lines like hair-tubes; the cup-shapes of their neutrino leaves sparkled as her view of them shifted. But the trees seemed to be thinning: she discerned patches of Crust separating small, regular-looking stands of trees.

...And the exposed Crust was not bare: rectangular markings coated it, each perhaps a hundred mansheights across. The rectangles were characterized by slight differences of color, varieties of texture. Some contained markings which swept across the patches in the direction of the Magfield like trapped vortex lines, but the patterns in others worked aslant from the Magfield direction - even perpendicular to it. And some bore no markings at all, save for random stipples of deeper color.

She stared into the South. The rectangular enclosures covered the Crust from this point in, she saw, marking it out in a patchwork that receded into the misty infinity beyond the end of the vortex lines. Small forms moved across the enclosures, patiently working: humans, dwarfed by distance and by the scale of the enclosures. Here and there she made out the boxy forms of Air-cars drifting through groups of humans, supervising and inspecting.

She felt humbled, dwarfed. The cap of Crust around the Pole was cultivated cultivated - but on an immense scale. - but on an immense scale.

Before this journey she had never seen any artifact larger than the Human Beings' Net. The car of Toba Mixxax, with its unending complexity, was impressive enough, she supposed - but these markings across the Crust were of another order entirely: artifice on a grand enough scale to challenge the curvature of the Star itself.

And put there by humans, like herself. She fought back awe.

She sought for the words Mixxax had used. "Ceiling-farm," "Ceiling-farm," she recalled at last. "Toba Mixxax, this is your... ceiling-farm." she recalled at last. "Toba Mixxax, this is your... ceiling-farm."

He laughed, an edge of bitterness in his voice. "Hardly. These fields are much too lush for the likes of me. No, we pa.s.sed the borders of my ceiling-farm long ago, while you were sleeping... poor as it is, you probably wouldn't have been able to distinguish it from the forest. When I picked you up we were about thirty meters from the Pole. We're within about five meters of Parz now; here the Air is thicker, warmer - the structure of the Star is different, just over the Pole itself - and people can live and work much higher, close to the Crust itself." He waved a hand, the reins resting casually in his grasp. "We're getting into the richest arable area. The Crust farms from this point in are owned by much richer folk than me. Or better connected... You wouldn't think it possible for one man to have as many brothers-in-law as Hork IV. Even worse than his father was. And..."

"What are they doing?"

"Who?"

She pointed to the fields. "The people up there."

He frowned, apparently surprised by the question. "They're coolies," he said. "What I mistook your people for. They're working the fields."

"Growing pap for the City," came a growl from behind them.

Dura turned, startled. Adda was awake; though his pus-filled eyecups were as sightless as before, he held himself a little stiffer in his coc.o.o.n of clothes and rope and his mouth was working, bubbles of spittle erupting from its comer.

Dura swam quickly to his side. "I'm sorry we woke you," she whispered. "How are you feeling?"

His mouth twisted and his throat bubbled, in a ghastly parody of a laugh. "Oh, terrific. What do you think? If you were any better-looking I'd invite you in here to keep me warm."

She snorted. "Don't waste your Air on stupid jokes, you old fool." She tried to adjust the position of his neck, smoothing out rucks in the rolled-up cloth around it.

Each time she touched him he winced.

Toba Mixxax turned. "There's food in that locker," he said, pointing. "We've still a long way to go."

In the place he'd indicated there was a small door cut into the wall, fixed by a short leather thong; opening it, Dura found a series of small bowls, each covered by a tight-fitting leather skin. Peeling away one of the skins she found pads of some pink, fleshy substance, each about the size of her palm. She took a pad and nibbled at it.

It was about as dense as meat, she supposed, but with a much softer texture. And it was delicious - like the leaves of the trees, she thought. But, as far as she could tell from her small sample, a lot denser and more nutritious than any leaf.

When was the last time she had eaten? It was all she could do not to cram the strange food into her own mouth.

She pulled three of the food pads out of the bowl, then covered over the bowl and stowed it away in its cupboard, desperate that the heavily scented photons which seeped from the food shouldn't wake up Farr.

She held a pad to Adda's lips. "Eat," she ordered.

"City man's pap," he grumbled; but, feebly, he bit into the pad and chewed at it.

"There's nothing wrong with it," she whispered as she fed him. "It's just food."

"And it's good for you," Toba Mixxax called in a loud whisper, turning in his seat to watch. "It's better for your health than meat, in fact. And..."

"But what is it?" Dura asked.

"Why, it's bread, of course," he said. "Made from wheat. From my ceiling-farm. What did you think it was?"

"Ignore him," Adda rasped. "And don't give him the satisfaction of asking what wheat is. I can see you want to."

"You can't see any d.a.m.n thing," she said absently. She paused. "Well, what is is wheat, anyway?" wheat, anyway?"

"Cultivated gra.s.s," Toba said. "The stuff which grows wild in the forest is good enough for Air-pigs, but it wouldn't keep you or me alive long. But wheat is a special type of gra.s.s, a strain which needs to be tended and protected - but which contains enough proton-rich compounds from the Crust to feed people."

"On pap," Adda growled.

"Not pap. Bread," Mixxax said patiently.

Dura frowned. "I don't think I understand. Air-pigs eat gra.s.s and we eat pigs. That's the way things work. What's wrong with that?"

Mixxax shrugged. "Nothing, if you don't have the choice. And if you want to spend your life chasing around forests in search of pigs. But the fact is, per cubic micron of Crust root ceiling, you can get more food value out of wheat than grazing pigs. And it's economically more efficient in terms of labor to run wheat ceiling-farms rather than pig farms." He laughed, with infuriating kindness. "Or to hunt wild pigs, as you people do. After all, wheat stays in one place. It doesn't jetfart around the forest, or attack old men." He looked sly. "Anyway, there are some things you won't get except from cultivated crops. Beercake, for instance..."

"Efficient, "Adda hissed. "That was one of the words they used when they drove us away from the Pole." "Adda hissed. "That was one of the words they used when they drove us away from the Pole."

Dura frowned. "Who drove us away?"

"The authorities in Parz," he said, his sightless eyes leaking disconcertingly. "I'm talking of a time ten generations ago, Dura... We don't talk of these things any more. The princelings, the priests, the Wheelwrights. Drove us away from the thick, warm Air of the Pole and out into the deserts upflux. Drove us out for our faith, because we looked to a higher authority than them. Because we wouldn't work on their ceiling-farms; we wouldn't accept slavery. Because we wouldn't be efficient." efficient."

"Coolies aren't slaves," Toba Mixxax said heatedly. "Every man and woman is free in the eyes of the law of Parz City, and..."

"And I'm a Xeelee's grandmother," Adda said wearily. "In Parz, you are as free as you can afford to be. If you're poor - a coolie, coolie, or a coolie's son - you've no freedom at all." or a coolie's son - you've no freedom at all."

Dura said to Adda, "What are you talking about? Is this how you knew where Toba was from - because we were from Parz City too, once?" She frowned. "You've never told me this. My father..."

Adda coughed, his throat rattling. "I doubt if Logue knew. Or, if he did, if he cared. It was ten generations ago. ten generations ago. What difference does it make now? We could never return; why dwell on the past?" What difference does it make now? We could never return; why dwell on the past?"

Mixxax said absently, "I still haven't worked out what to do if you incur costs for the old man's medical treatment."

"It doesn't take much imagination to guess," Adda hissed. "Dura, I told you to drive away this City man."

"Hush," she told him. "He's helping us, Adda."

"I didn't want his help," Adda said. "Not if it meant going into Parz itself." He thrashed, feebly, in his coc.o.o.n of clothes. "I'd rather die. But I couldn't even manage that now."

Frightened by his words, Dura pressed against Adda's shoulders with her hands, forcing him to lie still.

Toba Mixxax called cautiously, "You mentioned 'Xeelee' earlier."

Dura turned to him, frowning.

He hesitated. "Then that's your faith? You're Xeelee cultists?"

"No," Dura said wearily. "If that word means what I think it means. We don't regard the Xeelee as G.o.ds; we aren't savages. But we believe the goals of the Xeelee represent the best hope for..."

"Listen," Toba said, more harshly, "I don't see that I owe you any more favors. I'm doing too much for you already." He chewed his lip, staring out at the patterned Crust through his window. "But I'll tell you this anyway. When we get to Parz, don't advertise your faith - your belief, about the Xeelee. Whatever it is. All right? There's no point looking for trouble."

Dura thought that over. "Even more trouble than following a wheel?"

Adda turned blind eyes to her. Mixxax twisted, startled. "What do you know about the Wheel?"

"Only that you wear one around your neck," she said mildly. "Except when you think you need to hide it."

The City man yanked on his reins angrily.

Adda had closed his eyes and breathed noisily but steadily, evidently unconscious once more. Farr still slept. With a pang of guilt, Dura rammed the last morsels of the food - the bread bread - into her mouth, and slid forward to rejoin Mixxax at his reins. - into her mouth, and slid forward to rejoin Mixxax at his reins.

She gazed through the windows. Bewildering Crust detail billowed over her head. Even the vortex lines seemed to be racing past her, and she had a sudden, jarring sensation of immense speed; she was plummeting helplessly toward the mysteries of the Pole, and the future.

Toba studied her, cautious but with traces of concern. "Are you all right?"

She tried to keep her voice steady. "I think so. I'm just a little taken aback by the speed of this thing, I suppose."

He frowned and squinted out through his window. "We're not going so fast. Maybe a meter an hour. After all, it's not as if we've got to work across the Magfield; we're simply following the flux lines home... To my home, anyway. And, this far downflux, the pigs are getting back the full strength they'll have at the Pole. There they could reach maybe twice this speed, with a clear run." He laughed. "Not that there's any such thing as a clear run in Parz these days, despite the ordinances about cars inside the City. And the top teams..."

"I've never been in a car before," she hissed, her teeth clenched.

He opened his mouth, and nodded. "No. True. I'm sorry; I'm not very thoughtful." He mused, "I guess I'd find it a little disconcerting if I'd never ridden before - if I hadn't been riding since I was a child. No wonder you're feeling ill. I'm sorry; maybe I should have warned you. I..."

"Please stop apologizing."

"Anyway, we've made good time. Considering it's such a h.e.l.l of a long way from the Pole to my ceiling-farm." His round face creased with anger. "Humans can't survive much more than forty, fifty meters from the Pole. And my ceiling-farm is right on the fringe of that, right on the edge of the hinterland of Parz. So far upflux the Air tastes like glue and the coolies are weaker than Air-piglets... How am I supposed to make a living in conditions like that?" He looked at her, as if expecting an answer.

"What's a meter?"

"...A hundred thousand mansheights. A million microns." He looked deflated, his anger fading. "I don't suppose you know what I'm talking about. I'm sorry; I..."

"How deep is the Mantle?" she asked impulsively. "From Crust to Quantum Sea, I mean."

He smiled, his anger evaporating visibly. "In meters, or mansheights?"

"Meters will do."

"About six hundred."

She nodded. "That's what I've been taught, too."

He studied her curiously. "You people know about things like that?"

"Yes, we know about things like that," she said heavily. "We're not animals; we educate our children... even though it takes most of our energy just to keep alive, without clothes and cars and Air-boxes and teams of captive Air-pigs."

He winced. "I won't apologize again," he said ruefully. "Look... here's what I know." Still holding his reins loosely, he cupped his long-fingered, delicate-looking hands into a ball. "The Star is a sphere, about twenty thousand meters across."

She nodded. Two thousand million mansheights. Two thousand million mansheights.

"It's surrounded by the Crust," he went on. "There's three hundred meters of that. And the Quantum Sea is another ball, about eighteen thousand meters across, floating inside the crust.

She frowned. "Floating?"