Guards! Guards! (Discworld 8)

All he had to do was hide the book, or drop on to the thief's head and unscrew it by the ears.

He stared into the darkness again . . .

But that would be interfering with the course of history. Horrible things could happen. The Librarian knew all about this sort of thing, it was part of what you had to know before you were allowed into L-space. He'd seen pictures in ancient books. Time could bifurcate, like a pair of trousers. You could end up in the wrong leg, living a life that was actually happening in the other leg, talking to people who weren't in your leg, walking into walls that weren't there any more. Life could be horrible in the wrong trouser of Time.

Besides, it was against Library rules.[18] The assembled Librarians of Time and Space would certainly have something to say about it if he started to tinker with causality.

He closed the book carefully and tucked it back into the shelf. Then he swung gently from bookcase to bookcase until he reached the doorway. For a moment he stopped and looked down at his own sleeping body. Perhaps he wondered, briefly, whether to wake himself up, have a little chat, tell himself that he had friends and not to worry. If so, he must have decided against it. You could get yourself into a lot of trouble that way.

Instead he slipped out of the door, and lurked in the shadows, and followed the hooded thief when it came out clutching the book, and waited near the dread portal in the rain until the Elucidated Brethren had met and, when the last one left, followed him to his home, and murmured to himself in anthropoid surprise . . .

And then ran back to his Library and the treacherous pathways of L-space.

...

By mid-morning the streets were packed, Vimes had docked Nobby a day's salary for waving a flag, and an air of barbed gloom settled over the Yard, like a big black cloud with occasional flashes of lightning in it.

“ 'Get up in a high place', ” muttered Nobby. “That's all very well to say.”

“I was looking forward to lining the streets,” said Colon. “I'd have got a good view.”

“You were going on about privilege and the rights of man the other night,” said Nobby accusingly.

“Yes, well, one of the privileges and rights of this man is getting a good view,” said the sergeant. “That's all I'm saying.”

“I've never seen the captain in such a filthy temper,” said Nobby. “I liked it better when he was on the drink. I reckon he's-”

“You know, I think Errol is really ill,” said Carrot.

They turned towards the fruit basket.

“He's very hot. And his skin looks all shiny.”

“What's the right temperature for a dragon?” said Colon.

“Yeah. How do you take it?” said Nobby.

“I think we ought to ask Lady Ramkin to have a look at him,” said Carrot. “She knows about these things.”

“No, she'll be getting ready for the coronation. We shouldn't go disturbing her,” said Colon. He stretched out his hand to Errol's quivering flanks. “I used to have a dog that-arrgh! That's not hot, that's boiling!”

“I've offered him lots of water and he just won't touch it. What are you doing with that kettle, Nobby?”

glared at him and threw the window open.

The fog rolled in, in a slow, yellow-edged waterfall.

“We reckon it must of flown away,” said Colon's voice, behind him.

Vimes stared up into the heavy, rolling clouds.

“Hope it clears up for the coronation,” Colon went on, in a worried voice. “You all right, sir?”

It hasn't flown away, Vimes thought. Why should it fly away? We can't hurt it, and it's got everything it wants right here. It's up there somewhere.

“You all right, sir?” Colon repeated.

It's got to be up high somewhere, in the fog. There's all kinds of towers and things.