'I see. It's all rather untidy.'

'That's soldiers for you,' Brigonius said. 'Their work is solid and fast, but it's always functional rather than elegant.'

'Perhaps, but look around you! This is more than a wall, Brigonius. It is like one immense town that stretches eighty miles from coast to coast. I live in Rome itself and have never seen anything like it-I daresay there is nothing like it in all the world. But here it is in Britain, and you built it, Brigonius. And even when Rome is gone-oh, don't argue, our Emperor, who rules the wreckage of vanished empires himself, has a profound sense of the mortality of all things-even when the Romans are forgotten this Wall's mighty ruins will strike awe.'

He said impulsively, 'You know, you remind me of your mother.'

She shot him a look of suspicion. 'What do you mean by that?'

He held up his hands. 'Only her best qualities. When we first rode up from Rutupiae together-do you remember? She spoke to me, and it was as if I was seeing my own country through her eyes. So it is now with you.'

She pursed her lips. 'I think you're trying to compliment me.'

He sighed. 'But that woman keeps coming between us, doesn't she?'

'Yes, she does. Shall we ride on?'

They walked their horses further along the line of the Wall, and the sun rose steadily into the sky. Brigonius talked of his wife, his boys; she spoke of her own children who were growing up in such unimaginably different circumstances. And they spoke of old times, of Karus, long retired to Camulodunum-'I've had enough of history,' he had protested, 'all I want is life!'-and old Tullio, who had completed his twenty-five years in the army, filled a sprawling farm with a brood of red-haired grandchildren, continued to use his own mighty cock as a reference-point in every conversation, and died peacefully in his bed.

They halted on another bit of high ground, overlooking still more of the Wall as it marched on out of sight.

'You told me before that it felt as if I still belonged at your side.'

'You said it for me,' he reminded her gently.

'You thought it, though.'

'That's true.'

'And do you still think so now?'

He said honestly, 'I don't know. Too much has happened.'

'Yes. For us to be together the tapestry of time would have to be unpicked and woven again-wouldn't it? Perhaps if I had stayed in Brigantia all those years ago, rather than leaving with my mother. Or if you had given up all this to come with me to Rome.'

He shrugged. 'What's the point of speculating that way? You can't change history.'

'No. But, Brigonius-what if you could? For that is what my mother believes is the meaning of the Prophecy.'

In the intervening years he had all but forgotten Severa's mysterious document. 'That old bit of spookiness. Does it still exist?'

'Yes. And in a way it has been fulfilled, or so my mother believes. There are three lines relevant to our century, she thinks.'

Relevant to our century. Despite the gathering warmth of the day Brigonius shivered. 'Are there words relevant to other centuries, then?'

'Oh, yes,' she said. 'I always did argue with my mother about whether the Prophecy was more than just a tool for her to further her ambitions. Once her plans imploded she started to think about that. And she has decided the Prophecy is a warning from the future, that a Weaver of history has sent it back in order to influence our times-which to him would be the past.'

'And what do you think?'

'I still believe it all has something to do with Christ. Remember, the Prophecy was delivered at the birth of my forefather Nectovelin, who, it happened, was born in the same year as Jesus of Judea. I think the Prophecy actually has some connection to the destiny of Christianity, and this business of conquering provinces and building walls is all incidental. My mother denies this, though; she's nothing if not a loyalist to the gods of Rome. We've always argued about Jesus…But it's not the future outcome of the Prophecy that concerns me now but its present.'

'What do you mean?'

'The Prophecy is the issue of my mother's supposed sedition. The Emperor's court have always been suspicious of the Prophecy. Now she has been accused of subversion. And where better to investigate the case than here, where the Prophecy originated?'

'So that's why Sabinus was sent here.' They sat for a moment, with the Wall splayed brightly across the countryside around them. Brigonius said sadly, 'You know, here we are talking of mothers and emperors, of walls and prophecies. We aren't talking about us.'

'But there isn't really an us to talk about, is there?'

'No,' he said hotly. 'But I will always-'

She leaned from her horse and pressed a finger to his lips. 'It's better not said.'

He nodded. 'We should return. The day is advancing.'

'Of course.'

He spurred his horse, and the two of them trotted side by side back to Banna to resume the business of the day, the business of their bifurcated lives.

Three days later Galba Iulius Sabinus convened what he called a 'necessary meeting' on the matter of Claudia Severa.

Brigonius wanted nothing to do with it. He would have preferred Severa to pass through Brigantia and on again without his ever seeing her. But to his dismay he found he was summoned to the 'meeting'-and at the behest of Severa herself.

The meeting was held in the fort's office of sign-bearers. The little room, cluttered with records of soldiers' pay and savings and other military incidentals, was cramped, awkward. Oil lamps had been set out on the low tables to dispel the gloom of the poky room, and their sooty smoke flavoured the air. Small statues of Antinous, beautiful boy and lover of Hadrian, filled alcoves on the walls.

Brigonius found himself a place on a couch next to the prefect's aides. Severa wasn't here; she was late.

The prefect of Banna, Tullio's successor, was here with some of his aides, as was Primigenius, the shadow-thin freedman. Sabinus was the only man in a toga. He looked as if he never appeared in public without one these days.

Lepidina attended, apparently as reluctantly as Brigonius. She was dressed in what he thought of as her Roman 'uniform' of fine clothes, cosmetics and sculpted hair. The sturdy Brigantian woman he had glimpsed during that morning ride along the Wall might never have existed. She was at Sabinus's side, of course; she belonged there. But she smiled at Brigonius.

As they waited for the accused to show up Brigonius listened to the soldiers gossiping about dice games. The principals in the case, himself and Sabinus, Primigenius and Lepidina, were no more talkative than the many statues of Antinous.

Brigonius understood the game to be played out today. He knew from his own dealings with Roman law that all emperors were suspicious of rival centres of power. That included private enterprises such as his own partnership, the quarry business, whose operations were tightly controlled by contract law, and watched over by the provincial procurator. And this emperor in particular had an obsession with foretelling. In the harshness of his latter reign, consulting prophecies had become a sign of unhealthy ambition; it was said that Hadrian had had one of his own young relatives put to death for such a transgression.

You could see all this as a symptom of the Emperor's own decay, he thought. Just like all these statues of Antinous.

After two decades Hadrian would leave behind much to be admired. He had rebuilt his empire. Brigonius knew farmers who spoke admiringly of another of Hadrian's projects, lesser known than the Wall if no less mighty in scale: after his visit to Britain he had had drained much of the fenland in the east of the island, in the old homeland of the Iceni, opening up hundreds of miles of wholly new land for cultivation.