His useless legs stinking of rot and unguent, the monk had wheezed his way through an account of his prophecy - which turned out not to have been his at all, but gabbled out by a young man called Aethelred, who had been abandoned as a child, taken in by the monastery at Malmesbury, and then had his short, unhappy life curtailed by debauched brothers.

‘But not before he had left behind a remarkable body of work, studied and preserved by Aethelmaer and others.’

‘I saw them. Sketches of machines. Siege engines, catapults . . .’

‘I call the designs the Codex of Aethelmaer.’ Sihtric smiled. ‘The Engines of God.’

Orm struggled to remember the fantastic designs he had glimpsed just once, decades ago, and had never understood even then. ‘But they were just scribbles on parchment. In a lifetime of study, Aethelmaer could build none of them.’

‘Not quite,’ Sihtric said. ‘He did try to build one, remember? That was how he became crippled.’

Orm shook his head. ‘I never understood that. Why would you want to fly like a bird? Of course none of this means a thing unless you can actually build these mechanical marvels of yours.’

‘True enough,’ Sihtric said. ‘And I think you would be pleased to learn that I too have failed like Aethelmaer, wouldn’t you, Orm the Viking? Well, you’re about to be disappointed.’

Orm stared at him. ‘You mean the arbalest? Sihtric, can you really be developing gadgets, weapons, from the plans you stole from that mad monk?’

‘Interesting choice of words,’ Sihtric said. ‘Stole? I hardly think so. You met Aethelmaer. Old, crippled, he could do no more than have his arse wiped by some young novice, and probably enjoyed it too.’

‘Your talk is sometimes filthy for a priest,’ Orm said.

‘Well, I’m a filthy sort of priest. Anyhow Aethelmaer’s laborious mechanical sketching would have gone no further when he died, if not for my “stealing”. Am I not honouring his legacy, by trying to pursue the designs he left?

‘And, “gadgets”? You make them sound like toys. These are engines, Orm. Engines of war - and, perhaps, of peace. Come now. Let me show you.’ Sihtric spurred his horse forward.

Orm, overwhelmed, followed.

XI

XI

Robert and Moraima walked out of the mosque into dazzling daylight.

They headed down to the river, where waterwheels turned with a creak of wooden gears - Moraima said the wheels were called norias - and boats with colourful sails steered through the arches of the Roman bridge. On the bank, amid a clinking of coins, vendors sold food and water and parasols.

Moraima said, ‘You were affected by the mosque, weren’t you? Not everybody is. I think you’re deep, Robert son of Orm.’

‘Am I?’ He laughed. ‘Well, maybe compared to Ghalib and Hisham.’

‘Now you’re being jealous, and that’s not deep. I can’t always tell what you’re thinking, though. What you’re feeling.’