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 damn thing,” she said absently. She paused. “Well, what is wheat, anyway?”

“Cultivated grass,” 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 grass, 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 grass 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.”

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.”

“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, 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. 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 cocoon 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 gods; 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 — 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…”