Hisham stood beside Ghalib. Attendants fussed around, orchestrated by a portly man in pristine white robes. When he saw the visitors this man approached them. His face, round and sleek, looked as if it had been dipped in oil. He held his hands before him; small like a child’s, they were scrubbed pink-clean, and showed no signs of calluses or scars. He said to Sihtric, ‘Father. We have met before.’ His accent was strange. ‘My name is Abu Yusuf Yunus.’

‘Ah, yes. The Egyptian.’

‘My grandfather was Egyptian,’ Abu Yusuf Yunus said stiffly. ‘I am related by marriage to the Banu Zuhr family. I am a close friend of Abd al-Malik, while my father studied general medicine with his father, Muhammad Ibn Marwan Ibn Zuhr. Furthermore my grandfather studied with al-Zahrawi. We followed the prescripts of the al-Tasrif in treating this poor child . . .’

Orm grunted, impatient, and he pulled Sihtric aside. ‘What’s he babbling about?’

‘Just establishing his credentials. Making sure I know who he is and where he stands. I told you, Orm, it’s all family with the Moors. They’re all Ibn this or Abu that, the son of him or the father of the other, their lineage carried like a flag. And these scholars are the same, all boasting about their academic lineage, who taught who what.’

Abu Yusuf Yunus, unable to make out their English words, walked towards the injured boy. In stilted Latin he said, ‘The arm was almost severed below the elbow by the waterwheel’s machinery - muscles, arteries and blood vessels all lacerated, the bone, too, all but cut through. To that extent the injury was like the result of a blow with a sword. But the lower arm was crushed, the flesh pulped and the bone ground up, as if the boy had been trampled, say.’ Ghalib looked up at him dimly, and submitted passively as the surgeon began briskly to unravel the bandages on his arm. ‘Your young Christian—’

‘Robert,’ Orm growled. ‘My son.’

‘Robert didn’t save the boy’s life merely by dragging him from the water, but by stemming the blood loss from the damaged arm. He tied it off with a bit of rope below the shoulder.’

‘I did that,’ Hisham said promptly. And he stared at Robert, as if daring him to contradict this naked lie.

‘Then you are a hero, as much as Robert - more so, perhaps, for you used your brain rather than your muscles. Well done. Well done indeed.’

Robert looked away. Orm put his hand on his shoulder.

The bandages removed, Abu Yusuf Yunus exposed the wounded arm. Flaps of crudely cut skin were folded over the stump and stitched with gut. The seams leaked blood and a yellowish pus. Abu Yusuf Yunus clapped his hands. Attendants came bustling up with bowls of water and oils, and began to mop the wound. Ghalib twisted, but the attendants held him down.