Tarcho faced the boy. ‘No. Never like that. A soldier is free in a way a slave never can be. It’s a good life.’

‘Why is it so good?’

‘Because the emperors need us. The whole of the empire, all of it, the cities and the walls and the forts, is like one vast farmyard designed to feed the army. Why? Because without us it would all collapse in a day. Have you heard of an emperor called Severus?’

‘Who?’

‘Came to Britain to put down a rising.’

‘Carausias?’

‘No, long before him. While he was here Severus took the whole of Britain, far to the north of the Wall, then his sons gave it away again. Long story. Anyhow Severus had to sort out a mess, and it was the army that sorted it for him, and Severus knew it. “Feed the soldiers,” he told his sons, “and let the rest rot.” Or words to that effect. Dead a hundred years, but he was right. And every emperor since has followed his advice.’

‘Should I join the army, Tarcho?’

Tarcho looked at the boy, surprised. ‘Well, you’d have to be bought out of your slavery ... Is that what you want? You’d have to fight for Rome, you know.’

‘That wouldn’t make me Roman.’

‘No, true. But if you aren’t Roman, what are you?’

‘What I always was. Brigantian.’

So, Thalius heard, fascinated, under the surface of Britannia the old nations survived, if only in the memory of slaves.

Audax said now, ‘I want to be like you. I’ve got the muscles. Look.’ He held up an arm, pitifully thin, and bent it to show a bicep like a walnut.

Tarcho grinned, and in a brief and uncharacteristic moment of tenderness, hugged the boy against his own massive chest.

‘Sweet to watch them,’ Aurelia whispered. ‘Like seeing an eight-year-old care for a three-year-old.’

Cornelius murmured, ‘I suggest we get on with our business, Thalius.’

Thalius took a breath. ‘Very well.’ He coughed loudly to announce his presence and walked into the kitchen.

Tarcho stood, surprised, dropping the mortar and pestle. Audax hid behind Tarcho. The kitchen staff were startled, and Thalius waved a hand at them, shooing them out.

Tarcho stepped forward. ‘Sir, is there something I can do for you?’

Thalius sighed. ‘Not you but your charge, I’m afraid. Audax! Step forward now.’

The slave obeyed without thinking, his head bowed. Tarcho stayed a step behind him.

Thalius bent and whispered, ‘I’m sorry about this, lad. You must show your back again. But it won’t be for long, and I promise you won’t be hurt. Is that all right?’

The boy didn’t reply. For all Tarcho’s good will the boy’s spirit remained a flicker.

Thalius straightened up. ‘Turn around and lift your tunic. You know what to do.’