"Yeah," said the red-haired girl, in the garden of the deserted casino. "We seen her, me and Paolo both seen her. She come through here days ago."

Father Gomez said, "And do you remember what she looked like?"

"She look hot," said the little boy. "Sweaty in the face, all right."

"How old did she seem to be?"

"About..." said the girl, considering, "I suppose maybe forty or fifty. We didn't see her close. She could be thirty, maybe. But she was hot, like Paolo said, and she was carrying a big rucksack, much bigger than yours, this big..."

Paolo whispered something to her, screwing up his eyes to look at the priest as he did so. The sun was bright in his face.

"Yeah," said the girl impatiently, "I know. The Specters," she said to Father Gomez, "she wasn' afraid of the Specters at all. She just walked through the city and never worried a bit. I ain' never seen a grownup do that before, all right. She looked like she didn' know about them, even. Same as you," she added, looking at him with a challenge in her eyes.

"There's a lot I don't know," said Father Gomez mildly.

The little boy plucked at her sleeve and whispered again.

"Paolo says," she told the priest, "he thinks you're going to get the knife back."

Father Gomez felt his skin bristle. He remembered the testimony of Fra Pavel in the inquiry at the Consistorial Court: this must be the knife he meant.

"If I can," he said, "I shall. The knife comes from here, does it?"

"From the Torre degli Angeli," said the girl, pointing at the square stone tower over the red-brown rooftops. It shimmered in the midday glare. "And the boy who stole it, he kill our brother, Tullio. The Specters got him, all right. You want to kill that boy, that's okay. And the girl, she was a liar, she was as bad as him."

"There was a girl, too?" said the priest, trying not to seem too interested.

"Lying filth," spat the red-haired child. "We nearly killed them both, but then there came some women, flying women...” '

"Witches," said Paolo.

"Witches, and we couldn' fight them. They took them away, the girl and boy. We don' know where they went. But the woman, she came later. We thought maybe she got some kind of knife, to keep the Specters away, all right. And maybe you have, too," she added, lifting her chin to stare at him boldly.

"I have no knife," said Father Gomez. "But I have a sacred task. Maybe that is protecting me against these, Specters."

"Yeah," said the girl, "maybe. Anyway, you want her, she went south, toward the mountains. We don' know where. But you ask anyone, they know if she go past, because there ain' no one like her in Ci'gazze, not before and not now. She be easy to find."

"Thank you, Angelica," said the priest. "Bless you, my children."

He shouldered his pack, left the garden, and set off through the hot, silent streets, satisfied.

After three days in the company of the wheeled creatures, Mary Malone knew rather more about them, and they knew a great deal about her.

That first morning they carried her for an hour or so along the basalt highway to a settlement by a river, and the journey was uncomfortable; she had nothing to hold on to, and the creature's back was hard. They sped along at a pace that frightened her, but the thunder of their wheels on the hard road and the beat of their scudding feet made her exhilarated enough to ignore the discomfort.

And in the course of the ride she became more aware of the creatures' physiology. Like the grazers' skeletons, theirs had a diamond-shaped frame, with a limb at each of the comers. Sometime in the distant past, a line of ancestral creatures must have developed this structure and found it worked, just as generations of long-ago crawling things in Mary's world had developed the central spine.

The basalt highway led gradually downward, and after a while the slope increased, so the creatures could freewheel. They tucked their side legs up and steered by leaning to one side or the other, and hurtled along at a speed Mary found terrifying, though she had to admit that the creature she was riding never gave her the slightest feeling of danger. If only she'd had something to hold on to, she would have enjoyed it.

At the foot of the mile-long slope, there was a stand of the great trees, and nearby a river meandered on the level grassy ground. Some way off, Mary saw a gleam that looked like a wider expanse of water, but she didn't spend long looking at that, because the creatures were making for a settlement on the riverbank, and she was burning with curiosity to see it.

There were twenty or thirty huts, roughly grouped in a circle, made of, she had to shade her eyes against the sun to see, wooden beams covered with a kind of wattle-and-daub mixture on the walls and thatch on the roofs. Other wheeled creatures were working: some repairing a roof, others hauling a net out of the river, others bringing brushwood for a fire.

So they had language, and they had fire, and they had society. And about then she found an adjustment being made in her mind, as the word creatures became the word people. These beings weren't human, but they were people, she told herself; it's not them, they're us.

They were quite close now, and seeing what was coming, some of the villagers looked up and called to each other to look. The party from the road slowed to a halt, and Mary clambered stiffly down, knowing that she would ache later on.

"Thank you," she said to her, her what? Her steed? Her cycle? Both ideas were absurdly wrong for the bright-eyed amiability that stood beside her. She settled for, friend.

He raised his trunk and imitated her words:

"Anku," he said, and again they laughed, in high spirits.

She took her rucksack from the other creature ("Anku! Anku!") and walked with them off the basalt and on to the hard-packed earth of the village.

And then her absorption truly began.

In the next few days she learned so much that she felt like a child again, bewildered by school. What was more, the wheeled people seemed to be just as wonderstruck by her. Her hands, to begin with. They couldn't get enough of them: their delicate trunks felt over every joint, searching out thumbs, knuckles, and fingernails, flexing them gently, and they watched with amazement as she picked up her rucksack, conveyed food to her mouth, scratched, combed her hair, washed. In return, they let her feel their trunks. They were infinitely flexible, and about as long as her arm, thicker where they joined the head, and quite powerful enough to crush her skull, she guessed. The two finger-like projections at the tip were capable of enormous force and great gentleness; the creatures seemed to be able to vary the tone of their skin on the underside, on their equivalent of fingertips, from a soft velvet to a solidity like wood. As a result, they could use them for both a delicate task like milking a grazer and the rough business of tearing and shaping branches.

Little by little, Mary realized that their trunks were playing a part in communication, too. A movement of the trunk would modify the meaning of a sound, so the word that sounded like "chuh" meant water when it was accompanied by a sweep of the trunk from left to right, rain when the trunk curled up at the tip, sadness when it curled under, and young shoots of grass when it made a quick flick to the left. As soon as she saw this, Mary imitated it, moving her arm as best she could in the same way, and when the creatures realized that she was beginning to talk to them, their delight was radiant.

Once they had begun to talk (mostly in the wheeled people's language, although she managed to teach them a few words of English: they could say "anku" and "grass" and "tree" and "sky" and "river," and pronounce her name, with a little difficulty) they progressed much more quickly. Their word for themselves as a people was mulefa, but an individual was a zalif. Mary thought there was a difference between the sounds for he-zalif and she-ali, but it was too subtle for her to imitate easily. She began to write it all down and compile a dictionary.

But before she let herself become truly absorbed, she took out her battered paperback and the yarrow stalks, and asked the I Ching: Should I be here doing this, or should I go on somewhere else and keep searching?

The reply came: Keeping still, so that restlessness dissolves; then, beyond the tumult, one can perceive the great laws.

It went on: As a mountain keeps still within itself, thus a wise man does not permit his will to stray beyond his situation.

That could hardly be clearer. She folded the stalks away and closed the book, and then realized that she'd drawn a circle of watching creatures around her.

One said, Question? Permission? Curious.

She said, Please. Look.

Very delicately their trunks moved, sorting through the stalks in the same counting movement she'd been making, or turning the pages of the book. One thing they were astonished by was the doubleness of her hands: by the fact that she could both hold the book and turn the pages at the same time. They loved to watch her lace her fingers together, or play the childhood game of "This is the church, and this is the steeple," or make that over-and-over thumb-to-opposite forefinger movement that was what Ama was using, at exactly the same moment in Lyra's world, as a charm to keep evil spirits away.

Once they had examined the yarrow stalks and the book, they folded the cloth over them carefully and put them with the book into her rucksack. She was happy and reassured by the message from ancient China, because it meant that what she wanted most to do was exactly, at that moment, what she should do.

So she set herself to learning more about the mulefa, with a cheerful heart.

She learned that there were two sexes, and that they lived monogamously in couples. Their offspring had long childhoods, ten years at least, growing very slowly, as far as she could interpret their explanation. There were five young ones in this settlement, one almost grown and the others somewhere in between, and being smaller than the adults, they could not manage the seedpod wheels. The children had to move as the grazers did, with all four feet on the ground, but for all their energy and adventurousness (skipping up to Mary and shying away, trying to clamber up tree trunks, floundering in the shallow water, and so on), they seemed clumsy, as if they were in the wrong element. The speed and power and grace of the adults was startling by contrast, and Mary saw how much a growing youngster must long for the day when the wheels would fit. She watched the oldest child, one day, go quietly to the storehouse where a number of seedpods were kept, and try to fit his foreclaw into the central hole; but when he tried to stand up, he fell over at once, trapping himself, and the sound attracted an adult. The child struggled to get free, squeaking with anxiety, and Mary couldn't help laughing at the sight, at the indignant parent and the guilty child, who pulled himself out at the last minute and scampered away.

The seedpod wheels were clearly of the utmost importance, and soon Mary began to see just how valuable they were.

The mulefa spent mu............