‘But my family, mightiness,’ I burbled. ‘They won’t know where I am. Besides, it will be dark in only a few hours and I have no money for an inn. What am I to do when I get to Corinium? Or do you expect me to sleep beside the road?’

Lavinius gave me his icy pale-blue stare. ‘Citizen, I have complied with your request.’ (In fact he hadn’t – the driver was still bound.) ‘After that – as far as I’m concerned – the matter rests with you. If there are resultant problems, that’s not my affair. Perhaps you should have thought the matter through a little more.’ He turned to the steward, who was hovering nearby. ‘Slave, do as this pavement-maker says. Cut this scoundrel’s bonds then go and fetch the iron-smith to strike the fetters off his feet. If he tries to run away, arrest the citizen.’

The steward stepped forward and drew out a long knife from his belt. He pulled the driver roughly up onto his knees, causing him to groan in agony and, propping him in that position against the sacks, began – none too gently – to hack at the rope tethered between the feet and hands. As he worked, the pressure on the bonds was visibly increased and I could see the driver biting his lip to stop himself from crying out. Then the tether snapped and the captive, suddenly released from being tensioned like a bow, toppled over and fell forward on the floor.

The steward kicked him over on his side and knelt to cut the belt that bound the hands.

‘You need not let the prisoner go entirely,’ Publius put in. ‘He does not have to drive his raeda yet – that’s still outside of Glevum anyway. In fact he does not have to drive the thing at all. Lavinius, you could send them in your gig. There would be just room for both the prisoner and Libertus at a pinch, and that way you could keep the man in bonds throughout.’

That was quite an intelligent idea: not only did it appease Lavinius, it might save me a good deal of anxiety besides.

Before I could voice this, the raeda driver spoke up from the floor – unbowed as ever, it appeared. ‘The box containing all Audelia’s wedding-gifts is still inside my coach – at least I hope it is – and I imagine you will want it back? There would be not room to take that with us in the gig.’

It earned him a savage thump across his back from the steward. Lavinius scowled at the prisoner’s impudence, and Publius looked affronted at this challenge to his words. For two quadrans, I could see, he would wash his hands of this.

I did not wish to lose the only ally that I had, so I gave him what I hoped was an ingratiating smile. ‘Citizen Publius, with the greatest of respect, that raeda is the last place that Audelia was seen. I would like to stop and take a look at it. There may be signs of struggle, or some other sort of clue. Perhaps – as you suggest – the gig could take us to the gates, and then we could go on in the raeda after that. The man you set to guard it could travel on with us, in the front so that the raedarius couldn’t run away. The gig meanwhile, could bring the box back here.’

Publius frowned. ‘The slave I left on guard is not mine to command. He was borrowed from the pontifex, and will be wanted in the temple later on tonight, I’m sure.’

‘Then Fiscus, perhaps, could help me,’ I ventured, hopefully.

‘But he was only lent to you to be a guide, I think. Marcus Septimus expects him to be here when he arrives. I’m sorry, Libertus, you will have to watch over the raedarius yourself. I only wish that I was free to come with you, myself, but I cannot desert the birthday feast tonight, at which Lavinius is kind enough to have named me as chief guest. Perhaps, in the circumstances, the gig is good enough. We can arrange to have the box brought here another time.’

I was not anxious to travel all those miles in a crowded, bouncing, open gig. I had an inspiration. ‘But, supposing that we find Audelia?’ I said, praying that the raedarius would not betray my confidence in him by running off. ‘We would need some comfortable way of bringing her back here. She certainly couldn’t travel with us in the gig.’

Publius looked approvingly at me. ‘You are quite right, mosaic-maker. That is unthinkable. You may let the prisoner drive the raeda, when you get to it. In the meantime, steward, do not free his hands. Time enough for that when there’s an extra guard.’

The steward had already sat back on his knees and stopped sawing at the rope while he listened to all this. He glanced towards his owner with an enquiring look.

Lavinius nodded at him, clearly dismayed at this usurpation of his authority, and equally clearly unable to resist. ‘Very well. Let it be as Publius says. Bring the wretch to us when his feet are freed.’

‘Immediately, master!’ and with a parting shove to the unfortunate raedarius the slave got to his feet and went bustling away, no doubt to find the smith.

‘We should instruct the gig-slave what to do. The man will want fresh horses, I expect.’ Lavinius was suddenly all brisk efficiency, evidently determined to resume command. He turned to his attendant boy. ‘Page, go and find the gig-slave and tell him what’s required. Publius, my friend, we two will go into the house and wash our feet and I will have someone bring some dates and wine.’

He had pointedly not invited me and I hesitated, not certain what to do, but Publius gestured to me to accompany them. ‘Libertus must come with us so we can devise a plan. If he does discover something I want to know at once, and we must make arrangements for sending messages.’

Lavinius scowled, but signalled his reluctant agreement with a nod and led the way back through the gate towards the house, though he made a point of taking Publius on ahead and talking to him in an undertone, making certain that I could not hear and leaving me to trail behind them with the remaining page.

In the colonnaded garden Publius stopped and turned to me. I was warming to this patrician more and more by now. He may have forced me to a bargain which I could ill afford but this was clearly not the outcome of ill-will – simply the failure of a hugely wealthy man to understand how much a hundred aureii seemed to humbler folk.

He illustrated the gulf between us by his next words, too. They were addressed to Lavinius but they were meant for me to hear, and once again seemed an attempt to help. ‘About accommodation, is it not the case that Marcus has a second town-house in Corinium? Given his very high opinion of his protégé, surely he would not object to Libertus staying there?’

In fact I knew my patron would be appalled at the idea. The place was shut up when he was not there, with only a handful of slaves to keep it clean and aired. Besides, I am a simple tradesman, not a Roman patrician. It is true that I did stay at his country villa once, when I was ill and he required my services, but I am not the class of guest he usually invites. The notion of my simply arriving at his Corinium town-house unannounced, demanding food and somewhere warm to sleep, was quite unthinkable.

How could I explain this to a man like Publius? I shook my head and followed him inside as a smirking Fiscus held open the door of the atrium for us, smiling at his erstwhile master and ignoring me.

‘Respected eminence,’ I muttered to Publius, once I was in the room, ‘I am a citizen of very humble rank, and though my patron is very kind to me I could not presume upon him in this way. The house is closed and providing hospitality for me – or any unexpected guest – might be difficult. In any case the servants do not know me there and, without a letter from His Excellence himself, I doubt that they would even let me in.’

The atrium was full of flowers and scented oil, and servants were already setting a pair of fine carved stools – one ebony, one ivory – on each side of the little table by the wall. Publius seemed to take this as his right, and sat down on the nearer one, saying with a smile, ‘Would it help if I wrote a letter to the house myself.’

‘What would be really helpful,’ I said urgently, crouching on a lower footstool which Fiscus pointedly had set for me, ‘would be for me to stay at the lodging-house where Audelia stayed last night and where she changed coaches with Lavinia. I might learn something very helpful there.’

Lavinius had already settled on the ebony chair, dropping his cloak where the slave would pick it up and said, with a sneer, ‘They would not take a stranger they did not expect – they require a letter sent on in advance – that is the very reason that we chose their services. It keeps out the common class of travellers.’

A thoughtful frown crossed Publius’s pudgy face. ‘Suppose I wrote a letter to them, instead, explaining who I was, and gave it to Libertus to carry to the house. I am quite sure they would admit him then.’

Fiscus expressed his evident disdain by raising one eyebrow at Lavinius, but our host did not respond. He turned to the house-slave who was already at his side with a silver salver piled with cheese and grapes: I would wager the hundred aureii that these would not be sour. Lavinius selected one and signalled for some wine, before remarking smoothly, ‘The pavement-maker said he had no money for an inn, I think. And this one is not cheap.’

Publius selected a piece of proffered cheese. ‘I was prepared to offer a reward – or even pay a ransom – for Audelia’s return. I daresay I can undertake to pay for this. I will stop there and settle matters personally, on my way back to Londinium. Perhaps I could even stay there overnight myself, instead of using the military inns as I did on my way here. Courtesy of the provincial governor, of course.’ He smiled at me. ‘Of course, if Libertus is successful in his search, I will have my bride with me by then. So, Lavinius, if you would arrange a wax writing-block for me – or a sheet of bark-paper and some ink – I will compose a note. I have a seal-ring, if you have some wax. Fiscus can fetch the materials, perhaps, if your slaves are—’

He broke off as Modesta came rushing in, aghast. ‘Master.’ She flung herself breathless at her owner’s feet. ‘Your pardon, master, for disturbing you. There is a man on horseback here, whom I think that you should see.’

Lavinius made a lofty gesture with his long thin hand. ‘Doubtless one of the early banquet guests.’ He turned to Publius with a knowing smile. ‘This isn’t Rome, you know. A lot of humbler people don’t have water-clocks or well-positioned sundials, even now. Sometimes people find it very hard to judge the hour – especially if they know good wine awaits them here.’

Publius responded with the expected laugh, but Modesta did not smile. ‘But Master, it isn’t you that he is asking for. He insists he wants Audelia – no one else will do – and he won’t believe me when I say she isn’t here.’

The two patricians exchanged a startled glance, then Lavinius said sternly, ‘Show the fellow in.’ Modesta hurried off to do as she was told.

Publius put his cup down, half-troubled, half-relieved. ‘This must be a contact from the kidnappers. Or perhaps it is a trick. Do you think, Libertus . . . ?’

I never heard the rest, because at that moment the slave-girl reappeared, accompanied by one of the most enormous men I’d ever seen.