Brutha managed to get to his feet. The world revolved round him for a moment, adding a third astronomical theory to the two currently occupying the minds of local thinkers.
He peered out of the window. The red light was coming from fires all over Ephebe, but there was one huge glow over the Library.
‘Guerrilla activity,’ said Om. ‘Even the slaves are fighting. Can’t understand why. You think they’d jump at the chance to be revenged on their masters, eh?’
‘I suppose a slave in Ephebe has the chance to be free,’ said Brutha.
There was a hiss from the other end of the shed, and a metallic, whirring noise. Brutha heard Urn say, ‘There! I told you. Just a block in the tubes. Let’s get some more fuel in.’
Brutha tottered towards the group.
They were clustered round a boat. As boats went, it was of normal shape — a pointed end in front, a flat end at the back. But there was no mast. What there was, was a large, copper-coloured ball, hanging in a wooden framework towards the back of the boat. There was an iron basket underneath it, in which someone had already got a good fire going.
And the ball was spinning in its frame, in a cloud of steam.
‘I’ve seen that,’ he said. ‘In
‘Oh, it’s the walking Library,’ said Didactylos. ‘Yes. You’re right. Illustrating the principle of reaction. I never asked Urn to build a big one. This is what comes of thinking with your hands.’
‘I took it round the lighthouse one night last week,’ said Urn. ‘No problems at all.’
‘Ankh-Morpork is a lot further than that,’ said Simony.
‘Yes, it is five times further than the distance between Ephebe and Omnia,’ said Brutha solemnly. ‘There was a scroll of maps,’ he added.
Steam rose in scalding clouds from the whirring ball. Now he was closer, Brutha could see that half a dozen very short oars had been joined together in a star-shaped pattern behind the copper globe, and hung over the rear of the boat. Wooden cogwheels and a couple of endless belts filled the intervening space. As the globe spun, the paddles thrashed at the air.
‘How does it work?’ he said.
‘Very simple,’ said Urn. ‘The fire makes—’
‘We haven’t got time for this,’ said Simony.
‘—
‘Very philosophical,’ said Didactylos.
Brutha felt that he ought to stand up for Omnian progress.
‘The great doors of the Citadel weigh tons but are opened solely by the power of faith,’ he said. ‘One push and they swing open.’
‘I should very much like to see that,’ said Urn.
Brutha felt a faint sinful twinge of pride that Omnia still had anything he could be proud of.
‘Very good balance and some hydraulics, probably.’
‘Oh.’
Simony thoughtfully prodded the mechanism with his sword.
‘Have you thought of all the possibilities?’ he said.
Urn’s hands began to weave through the air. ‘You mean mighty ships ploughing the wine-dark sea with no—’ he began.
‘On land, I was thinking,’ said Simony. ‘Perhaps … on some sort of cart …’
‘Oh, no point in putting a boat on a cart.’
Simony’s eyes gleamed with the gleam of a man who had seen the future and found it covered with armour plating.
‘Hmm,’ he said.
‘It’s all very well, but it’s not philosophy,’ said Didactylos.
‘Where’s the priest?’
‘I’m here, but I’m not a—’
‘How’re you feeling? You went out like a candle back there.’
‘I’m … better now.’
‘One minute upright, next minute a draught-excluder.’{56}
‘I’m much better.’
‘Happen a lot, does it?’
‘Sometimes.’
‘Remembering the scrolls okay?’
‘I … think so. Who set fire to the Library?’
Urn looked up from the mechanism.
‘He did,’ he said.
Brutha stared at Didactylos.
‘
‘I’m the only one qualified,’ said the philosopher. ‘Besides, it keeps it out of the way of Vorbis.’
‘What?’
‘Suppose he’d read the scrolls? He’s bad enough as it is. He’d be a lot worse with all that knowledge inside him.’
‘He wouldn’t have read them,’ said Brutha.
‘Oh, he would. I know that type,’ said Didactylos. ‘All holy piety in public, and all peeled grapes and self-indulgence in private.’
‘Not Vorbis,’ said Brutha, with absolute certainty. ‘He wouldn’t have read them.’
‘Well,
Urn turned away from the bow of the boat, where he was feeding more wood into the brazier under the globe.
‘Can we all get on board?’ he said.
Brutha eased his way on a rough bench seat amidships, or whatever it was called. The air smelled of hot water.
‘Right,’ said Urn. He pulled a lever. The spinning paddles hit the water; there was a jerk and then, steam hanging in the air behind it, the boat moved forward.
‘What’s the name of this vessel?’ said Didactylos.
Urn looked surprised.