of Buddy, doing the necessary physical and mass metrics to allow her Net workspace to construct a horse that looked, acted, and rode exactly like the real thing.
It was a useful adjunct to your (admittedly invaluable) practice with the horse you were actually going to ride, especially when there might be four or five other people qualified to team with the same horse, and all fighting to get enough practice time… of which there was never enough even if there was just one of you. With a model, though, a simulated horse, you could at least make sure your own moves were right. And you could ride the sim for hours at a time without stopping, if you overrode the 'reality' constraints… one of the minor advantages to practicing virtually. You could ride it in the middle of the night if you liked, a process to which a normal horse would object violently.
The only problem was the actual design of the sim itself, which ran into big money. Megan had looked into the cost of professional character and movement profiling by some dedicated firm like eQuines Unlimited or The Horseman's Word, and had come away horrified. It was just too exorbitant to even think about, even if the family had been rich, which (as her father constantly reminded her) it was not. So Megan had started building the virtual Buddy herself, learning entirely too much about the art of simming live creatures in the process. He was a work literally in progress, and the only problem with it all was that Megan was an amateur, and wasn't ever entirely sure that she was getting it right.
She still wasn't sure. More, from the expression on Wilma's face, she got the feeling that Wil wasn't sure either. She reined in, stopped. 'I'm not sure about the way he's moving. You want to turn him clear?'
'No problem.' Wilma started to ride him back to the point from which she would once again begin the pattern. 'Workspace-'
'Listening.'
'Model change. Transparent mode.'
'Transparent mode enabled.'
— and suddenly Wilma was riding a horse made of brown glass. At least it looked that way. The skin was hardly there, and the inferred organs inside were just vague shadows, but the details of the horse's musculature and bone structure could clearly be seen as he went. Megan got lost in watching this, and stood in the middle of the arena, turning and turning again as Buddy went around with Wilma on his back, watching the bones and muscles move, watching the nature of the motion itself, looking for anything uneven, anything that would reveal where the problem lay.
'Leg yield?' Megan said.
'Okay.'
Wilma started the move, choosing the version which was usually done in the First 3 series of riders' tests, straight from the rail to the center line of the competition arena. Megan could just see her giving the signals: outside leg, inside rein, just a touch of each. Buddy had been walking straight forward. Now, keeping his body parallel to the rail, he began to walk at a thirty-degree angle from the fence, heading for the center of the arena. He ys doing this right, anyway, Megan thought with some slight relief, for he had performed it correctly for her as well. At least something's behaving consistently…
'Keep going?' Wilma said.
'Sure, why not? Take him through the next part, the traverse. Maybe you can sneak up on him with the circle and get him to forget to go straight.'
Wilma didn't comment, just kept going. Buddy began to follow the rail in a way that was correct for once, haunches out, progressing forward though his body was turned sideways. Smooth, Megan thought. She's really got the touch. If I can get her to show me that a few more times, maybe I can solve our problem-
The air filled with a phone-ringing noise. Megan rolled her eyes up in annoyance at the blue 'sky' and said, 'Megan O'Malley-'
There was no image, only voice. 'Megan, honey, hi, it's Mrs. Christensen.'
'Hi, Mrs. C., Wilma's here… '
'No, it wasn't Wilma I was looking for-'
That was moderately strange. Wilma reined in. 'Mom?'
'Hi, honey. I was looking for Burt.'
'Uh.' Wilma's face went taut with annoyance. 'He's not here.'
'No? I thought he was supposed to be with you girls.'
'Uh, no, Ma. We thought he was going to be, but he stood us up.' Wilma's expression got even grimmer. She swung down off Buddy.
'Oh. All right.' Wilma's mother didn't say anything further for a moment, and there was something strange about the way she didn't say it, so that Megan said, 'Was someone looking for him?'
'Uh, yes, his mother,' said Wilma's mom. 'She called me.
'And she didn't know where he was, either?'
Another of those odd silences. 'She said he was gone,' said Wilma's mother.
Wilma blinked at that. ' 'Gone?' Gone where?'
'She said he had taken some things and just left, and- Well, I don't know, she sounded kind of upset, and from what she said, Burt had been talking about leaving home, and, you know, kids say things like that, but they-'
'Oh, no,' Wilma whispered. Megan looked at her and was astonished to see that she had suddenly gone absolutely pale. In the bright sunlight it looked bizarre. At first she thought Wilma was going to faint, but then she realized the paleness had nothing to do with any strictly physical condition. It was fear.
'I've got to go,' Wilma said. 'Mom? Hang up, I'll be right there-'
The call from 'outside' clicked off. 'Uh, okay, sure,' Megan said, confused. 'But listen, Wil, practice tomorrow-'
'I don't know if I can. I'll call you.'
And Wilma deactivated her virtual-experience implant, and vanished.
Megan found herself standing there in the middle of the arena, alone in the sawdust except for the virtual Buddy, who stood there by her and then very gradually leaned over to start cribbing at the fence again.
'Workspace,' Megan said.
'Listening.'
'Shut down the Buddy model, please.'
'Default save from this point, or save from other time/ place point?'
'Default save.'
'Done.' The horse vanished, and a second later the competition arena was swept clear of his footprints, as if he'd never been there.
Megan stood there, her mind filling with awful things that she very much wanted to say, except that none of them would help the present situation, and besides, she could just hear her mother's voice saying reproachfully, 'And after that, what will you have left to say some day when you hit your thumb with a hammer?'
'I can think of a few things,' Megan muttered under her breath. 'Never mind.'
'Listening. Was that a command?'
'No. Sorry,' Megan said, and then smiled, a wry look. She might think about all the rude words she liked, but she still caught herself apologizing to the computer, which, however smart it might be, wasn't that smart. 'Revert to default configuration.'
The arena, the sawdust, the sunny day, all vanished. Suddenly she was standing in her workspace as it normally appeared, as an ancient, worn, white-stone amphitheater, fifty rows high, perfect right down to the worn seat numbers still to be felt shallowly graven into the seats. But the landscape surrounding it was no olive- overgrown Greek hillside or dusty Roman plain. Methane snow, blurring into near-invisibility when the wind picked it up and blew it, lay powdered bluish-white all over the surrounding cratered landscape of the satellite Rhea, only going tarnished gold near the horizon where the light of a swollen, setting Saturn shed a cold, white-gold radiance over everything. Sharp white points of stars burned down out of the blackness, and the little pallid Sun away off to the left, just past the spot where the curve of the amphitheater ended, threw long sharp shadows behind the rims of the nearest craters.
Megan sighed, for once in no mood for the beauty, and walked past her desk, which stood in the middle of the 'floor' of the amphitheater. It was covered and sur7 rounded with little geometric solids, some of them hovering
