"Nine stones, then."

"Hmm . . . should be about right . . . three miles hubward . . . you'll feel a slight lurch to the left, nothing to worry about. . ."

In a lightning movement, he grabbed her hand. He felt young and light-headed. The wizards back at the University would have been astonished.

"Let me take you away from all this."

He snapped his fingers.

There has to be at least an approximate conservation of mass. It's a fundamental magical rule. If something is moved from A to B, something that was at B has got to find itself at A.

And then there's momentum. Slow as the disc spins, various points of its radii are moving at different speeds relative to the Hub, and a wizard projecting himself any distance toward the Rim had better be prepared to land jogging.

The three miles to Lancre Bridge merely involved a faint tug, which Ridcully had been ready for, and he landed up leaning against the parapet with Esme Weatherwax in his arms.

The customs troll who had until a fraction of a second previously been sitting there ended up lying full length on the floor of the Great Hall, coincidentally on top of the Bursar.

Granny Weatherwax looked over at the rushing water, and then at Ridcully.

"Take me back this instant," she said. "You've got no right to do that."

"Dear me, I seem to have run out of power. Can't understand it, very embarrassing, fingers gone all limp," said Ridcully. "Of course, we could walk. It's a lovely evening. You always did get lovely evenings here."

"It was all fifty or sixty years ago!" said Granny. "You can't suddenly turn up and say all those years haven't happened."

"Oh, I know they've happened all right," said Ridcully. "I'm the head wizard now. I've only got to give an order and a thousand wizards will. . . uh . . . disobey, come to think of it, or say 'What?', or start to argue. But they have to take notice."

"I've been to that University a few times," said Granny. "A bunch of fat old men in beards."

"That's right! That's them!"

"A lot of 'em come from the Ramtops," said Granny. "I knew a few boys from Lancre who became wizards."

"Very magical area," Ridcully agreed. "Something in the air."

Below them, the cold black waters raced, always dancing to gravity, never flowing uphill.

"There was even a Weatherwax as Archchancellor, years ago," said Ridcully.

"So I understand. Distant cousin. Never knew him," said Granny.

They both stared down at the river for a moment. Occasionally a twig or a branch would whirl along in the current.

"Do you remember-"

"I have a . . . very good memory, thank you."

"Do you ever wonder what life would have been like if

you'd said yes?" said Ridcully.

"No."

"I suppose we'd have settled down, had children, grandchildren, that sort of thing . . ."

Granny shrugged. It was the sort of thing romantic idiots said. But there was something in the air tonight. . .

"What about the fire?" she said.

"What fire?"

"Swept through our house just after we were married.

Killed us both."

"What fire? I don't know anything about any fire?"

Granny turned around.

"Of course not! It didn't happen. But the point is, it might have happened. You can't say 'if this didn't happen then that would have happened' because you don't know everything that might have happened. You might think something'd be good, but for all you know it could have turned out horrible. You can't say 'If only I'd . . . ' because you could be wishing for anything. The point is, you'll never know. You've gone past. So there's no use thinking about it.

So I don't."

"The Trousers of Time," said Ridcully, moodily. He picked a fragment off the crumbling stonework and dropped it into the water. It went plunk, as is so often the case.

"What?"

"That's the sort of thing they go on about in the High Energy Magic building. And they call themselves wizards! You should hear them talk. The buggers wouldn't know a magic sword if it bit them on the knee. That's young wizards today. Think they bloody invented magic."

"Yes? You should see the girls that want to be witches these days," said Granny Weatherwax. "Velvet hats and black lipstick and lacy gloves with no fingers to 'em. Cheeky, too."

They were side by side now, watching the river.

"Trousers of Time," said Ridcully. "One of you goes down one leg, one of you goes down the other. And there's all these continuinuinuums all over the place. When I was a lad there was just one decent universe and this was it, and all you had to worry about was creatures breaking through from the Dungeon Dimensions, but at least there was this actual damn universe and you knew where you stood. Now it turns out there's millions of the damn things. And there's this damn cat they've discovered that you can put in a box and it's dead and alive at the same time. Or something. And they all run around saying marvellous, marvellous, hooray, here comes another quantum. Ask 'em to do a decent levitation spell and they look at you as if you've started to dribble. You should hear young Stibbons talk. Went on about me not inviting me to my own wedding. Me!"

From the side of the gorge a kingfisher flashed, hit the water with barely a ripple, and ricocheted away with something silver and wriggly in its beak.

"Kept going on about everything happening at the same time," Ridcully went on morosely. "Like there's no such thing as a choice. You just decide which leg you're heading for. He says that we did get married, see. He says all the things that might have been have to be. So there's thousands of me out there who never became a wizard, just like there's thousands of you who, oh, answered letters. Hah! To them, we're something that might have been. Now, d'you call that proper thinking for a growing lad? When I started wizarding, old 'Tudgy' Spold was Archchancellor, and if any young wizard'd even mentioned that sort of daft thing, he'd feel a staff across his backside. Hah!"

Somewhere far below, a frog plopped off a stone. "Mind you, I suppose we've all passed a lot of water since then."

It dawned gently on Ridcully that the dialogue had become a monologue. He turned to Granny, who was staring round-eyed at the river as if she'd never seen water before.

"Stupid, stupid, stupid," she said.

"I beg your pardon? I was only-"

"Not you. I wasn't talking to you. Stupid! I've been stupid. But I ain't been daft! Hah! And I thought it was my memory going! And it was, too. It was going and fetching!"

"What?"

"I was getting scared! Me! And not thinking clear!

Except I was thinking clear!"

"What!"

"Never mind! Well, I won't say this hasn't been . . . nice," said Granny. "But I've got to get back. Do the thing with the fingers again. And hurry."

Ridcully deflated a little.

"Can't," he said.

"You did it just now."

"That's the point. I wasn't joking when I said I couldn't do it again. It takes a lot out of you, transmigration."

"You used to be able to do it all the time, as I recall," said Granny. She risked a smile. "Our feet hardly touched the ground."

"I was younger then. Now, once is enough." Granny's boots creaked as she turned and started to walk quickly back toward the town. Ridcully lumbered after her.

"What's the hurry?"

"Got important things to do," said Granny, without turning around. "Been letting everyone down."

"Some people might say this is important."

"No. It's just personal. Personal's not the same as important. People just think it is."

"You're doing it again!"

"What?"