Carding knelt down awkwardly and felt the floor gingerly. He signalled to Spelter to do the same.

Spelter touched a surface that was smoother than stone. It felt like ice would feel if ice was slightly warm, and looked like ivory. While it wasn’t exactly transparent, it gave the impression that it would like to be.

He got the distinct feeling that, if he closed his eyes, he wouldn’t be able to feel it at all.

He met Carding’s gaze.

‘Don’t look at, um, me,’ he said. ‘I don’t know what it is either.’

They looked up at Coin, who said: ‘It’s magic.’

‘Yes, lord, but what is it made of?’ said Carding.

‘It is made of magic. Raw magic. Solidified. Curdled. Renewed from second to second. Could you imagine a better substance to build the new home of sourcery?’

The staff flared for a moment, melting the clouds. The Discworld appeared below them, and from up here you could see that it was indeed a disc, pinned to the sky by the central mountain of Cori Celesti, where the gods lived. There was the Circle Sea, so close that it might even be possible to dive into it from here; there was the vast continent of Klatch, squashed by perspective. The Rimfall around the edge of the world was a sparkling curve.

‘It’s too big,’ said Spelter under his breath. The world he had lived in hadn’t stretched much further than the gates of the University, and he’d preferred it that way. A man could be comfortable in a world that size. He certainly couldn’t be comfortable about being half a mile in the air standing on something that wasn’t, in some fundamental way, there.

The thought shocked him. He was a wizard, and he was worrying about magic.

He sidled cautiously back towards Carding, who said: ‘It isn’t exactly what I expected.’

‘Um?’

‘It looks a lot smaller up here, doesn’t it.’

‘Well, I don’t know. Listen, I must tell you-’

‘Look at the Ramtops, now. You could almost reach out and touch them.’

They stared out across two hundred leagues towards the towering mountain range, glittering and white and cold. It was said that if you travelled hubwards through the secret valleys of the Ramtops, you would find, in the frozen lands under Cori Celesti itself, the secret realm of the Ice Giants, imprisoned after their last great battle with the Gods. In those days the mountains had been mere islands in a great sea of ice, and ice lived on them still.

Coin smiled his golden smile.

‘What did you say, Carding?’ he said.

‘It’s the clear air, lord. And they look so close and small. I only said I could almost touch them-’

Coin waved him into silence. He extended one thin arm, rolling back his sleeve in the traditional sign that magic was about to be performed without trickery. He reached out, and then turned back with his fingers closed around what was, without any shadow of a doubt, a handful of snow.

The two wizards observed it in stunned silence as it melted and dripped on to the floor.

Coin laughed.

‘You find it so hard to believe?’ he said. ‘Shall I pick pearls from rim-most Krull, or sand from the Great Nef? Could your old wizardry do half as much?’

It seemed to Spelter that his voice took on a metallic edge. He stared intently at their faces.

Finally Carding sighed and said rather quietly, ‘No. All my life I have sought magic, and all I found was coloured lights and little tricks and old, dry books. Wizardry has done nothing for the world.’

‘And if I tell you that I intend to dissolve the Orders and close the University? Although, of course, my senior advisors will be accorded all due status.’

Carding’s knuckles whitened, but he shrugged.

‘There is little to say,’ he said. ‘What good is a candle at noonday?’

Coin turned to Spelter. So did the staff. The filigree carvings were regarding him coldly. One of them, near the top of the staff, looked unpleasantly like an eyebrow.

‘You’re very quiet, Spelter. Do you not agree?’

No. The world had sourcery once, and gave it up for wizardry. Wizardry is magic for men, not gods. It’s not for us. There was something wrong with it, and we have forgotten what it was. I liked wizardry. It didn’t upset the world. It fitted. It was right. A wizard was all I wanted to be.

He looked down at his feet.

‘Yes,’ he whispered.

‘Good,’ said Coin, in a satisfied tone of voice. He strolled to the edge of the tower and looked down at the street map of Ankh-Morpork far below. The Tower of Art came barely a tenth of the way towards them.

‘I believe,’ he said, ‘I believe that we will hold the ceremony next week, at full moon.’

‘Er. It won’t be full moon for three weeks,’ said Carding.

‘Next week,’ Coin repeated. ‘If I say the moon will be full, there will be no argument.’ He continued to stare down at the model buildings of the University, and then pointed.

‘What’s that?’

Carding craned.

‘Er. The Library. Yes. It’s the Library. Er.’

The silence was so oppressive that Carding felt something more was expected of him. Anything would be better than that silence.

‘It’s where we keep the books, you know. Ninety thousand volumes, isn’t it, Spelter?’

‘Um? Oh. Yes. About ninety thousand, I suppose.’

Coin leaned on the staff and stared.

‘Burn them,’ he said. ‘All of them.’

Midnight strutted its black stuff along the corridors of Unseen University as Spelter, with rather less confidence, crept cautiously towards the impassive doors of the Library. He knocked, and the sound echoed so loudly in the empty building that he had to lean against the wall and wait for his heart to slow down a bit.

After a while he heard a sound like heavy furniture being moved about.

‘Oook?’

‘It’s me.’

‘Oook?’

‘Spelter.’

‘Oook.’

‘Look, you’ve got to get out! He’s going to burn the Library!’

There was no reply.

Spelter let himself sag to his knees.

‘He’ll do it, too,’ he whispered. ‘He’ll probably make me do it, it’s that staff, um, it knows everything that’s going on, it knows that I know about it … please help me …’

‘Oook?’

‘The other night, I looked into his room … the staff, the staff was glowing, it was standing there in the middle of the room like a beacon and the boy was on the bed sobbing, I could feel it reaching out, teaching him, whispering terrible things, and then it noticed me, you’ve got to help me, you’re the only one who isn’t under the-’

Spelter stopped. His face froze. He turned around very slowly, without willing it, because something was gently spinning him.

He knew the University was empty. The wizards had all moved into the New Tower, where the lowliest student had a suite more splendid than any senior mage had before.

The staff hung in the air a few feet away. It was surrounded by a faint octarine glow.

He stood up very carefully and, keeping his back to the stonework and his eyes firmly fixed on the thing, slithered gingerly along the wall until he reached the end of the corridor. At the corner he noted that the staff, while not moving had revolved on its axis to follow him.

He gave a little cry, grasped the skirts of his robe, and ran.

The staff was in front of him. He slid to a halt and stood there, catching his breath.

‘You don’t frighten me,’ he lied, and turned on his heel and marched off in a different direction, snapping his fingers to produce a torch that burned with a fine white flame (only its penumbra of octarine proclaimed it to be of magical origin).

Once again, the staff was in front of him. The light of his torch was sucked into a thin, singing steam of white fire that flared and vanished with a ‘pop’.

He waited, his eyes watering with blue after-images, but if the staff was still there it didn’t seem to be inclined to take advantage of him. When vision returned he felt he could make out an even darker shadow on his left. The stairway down to the kitchens.

He darted for it, leaping down the unseen steps and landing heavily and unexpectedly on uneven flags. A little moonlight filtered through a grating in the distance and somewhere up there, he knew, was a doorway into the outside world.

Staggering a little, his ankles aching, the noise of his own breath booming in his ears as though he’d stuck his entire head in a seashell, Spelter set off across the endless dark desert of the floor.

Things clanked underfoot. There were no rats here now, of course, but the kitchen had fallen into disuse lately - the University’s cooks had been the best in the world, but now any wizard could conjure up meals beyond mere culinary skill. The big copper pans hung neglected on the wall, their sheen already tarnishing, and the kitchen ranges under the giant chimney arch were filled with nothing but chilly ash …

The staff lay across the back door like a bar. It spun up as Spelter tottered towards it and hung, radiating quiet malevolence, a few feet away. Then, quite smoothly, it began to glide towards him.

He backed away, his feet slipping on the greasy stones. A thump across the back of his thighs made him yelp, but as he reached behind him he found it was only one of the chopping blocks.

His hand groped desperately across its scarred surface and, against all hope, found a cleaver buried in the wood. In an instinctive gesture as ancient as mankind, Spelter’s fingers closed around its handle.

He was out of breath and out of patience and out of space and time and also scared, very nearly, out of his mind.

So when the staff hovered in front of him he wrenched the chopper up and around with all the strength he could muster …

And hesitated. All that was wizardly in him cried out against the destruction of so much power, power that perhaps even now could be used, used by him…

And the staff swung around so that its axis was pointing directly at him.

And several corridors away, the Librarian stood braced with his back against the Library door, watching the blue and white flashes that flickered across the floor. He heard the distant snap of raw energy, and a sound that started low and ended up in zones of pitch that even Wuffles, lying with his paws over his head, could not hear.

And then there was a faint, ordinary tinkling noise, such as might be made by a fused and twisted metal cleaver dropping on to flagstones.

It was the sort of noise that makes the silence that comes after it roll forward like a warm avalanche.

The Librarian wrapped the silence around him like a cloak and stood staring up at the rank on rank of books, each one pulsing faintly in the glow of its own magic. Shelf after shelf looked down[14] at him. They had heard. He could feel the fear.

The orang-utan stood statue-still for several minutes, and then appeared to reach a decision. He knuckled his way across to his desk and, after much rummaging, produced a heavy key-ring bristling with keys. Then he went back and stood in the middle of the floor and said, very deliberately, ‘Oook.’

The books craned forward on their shelves. Now he had their full attention.