I shook my head. This was not the time or place to tell her that the information I’d received only served to make me more bemused. ‘Only that I need to go out to the farm and speak to Paulinus as soon as possible.’

She smirked triumphantly. ‘That won’t be difficult. I’ve found the donkey-boy for you. He remembers exactly where he took the writing-block and he will take you there, although it’s quite a walk, he says – several miles at least.’

I nodded, though not without an inward sigh. I am quite used to walking from my roundhouse into Glevum town, and that is a walk of several miles as well, but this was different. I couldn’t take my time. Two females were already dead and another one was missing without trace: I wanted to ask more questions as soon as possible.

The urchin tugged my toga. ‘You could come up on my donkey, citizen, if you don’t mind sitting at the back and hanging on. Long Ears is used to carrying panniers so he’ll bear you easily, though he can be a stubborn old creature when he tries. I may have to give you a branch-switch to help to urge him on.’ His grimy face split in a mocking grin. ‘Might not be very dignified, but it would get you there – a little bit quicker than walking anyway, there are a lot of hills and valleys between here and the farm. Or I could lead Long Ears and walk along beside, though that would obviously be slower and cost a little more.’

I was about to protest my complete lack of ready cash, but Priscilla said at once, ‘I’ve told him, citizen, that we will put it on your bill, and pay him what is owed when Publius pays us.’ She saw my look and added urgently, ‘I had to promise something or he wouldn’t have agreed. The boy has to make a living, after all – and he can’t be doing other errands if he’s guiding you.’

I was obliged to see the force of this and I agreed the terms, wondering what Publius was going to say to this. No one had mentioned hiring donkey-boys.

Priscilla smiled. ‘I will leave you to it, then, and go back to the house and see if the undertakers’ women have finished dealing with the nurse’s corpse. If so the raedarius can take it back to Lavinius again, as you sensibly suggested, citizen.’

‘You will send news back with them, and warn the family what has happened, I suppose?’

She looked pityingly at me, as though I were foolish to have asked. ‘I’ll do more than that. I’ll send the horseman off at once to tell them to expect her body later in the day, then they can make arrangements for a pyre. No doubt they’ll know if she was a member of the funeral-guild.’

I nodded. It was probable. Most slaves in wealthy families belonged to such a guild, which – for a small subscription – ensured a decent send-off after death. Some masters, like Marcus, paid the fee themselves, it saved them having to arrange a private pyre.

I said, ‘If not, I suppose Cyra and Lavinius will do something for their slave.’

‘Then, with your permission,’ Priscilla said, ‘I’ll send that flask back too, since clearly at one time it belonged to them. The household would expect to have it back, I’m sure. It is still a valuable object and if it can’t be repaired, at least the metal could be used again. Though whether Cyra will want to use it in any form at all, when she hears that it was used to murder that poor nurse, only Juno knows. Perhaps they’ll use it as a grave-offering for the corpse.’ She looked from left to right as though we might be overheard, then added in a whisper, ‘Should I get Ascus to tell her that we think it was tampered with by Druids?’

I remembered the courtyard and the finding of the flask. What was it about the scene that still faintly troubled me? The little jug had been exactly where it would have bounced if it had been thrown out of the window-space above . . . Of course! I was a threefold idiot! I took a sharp breath and turned to Trullius’s wife. ‘Better perhaps, for Ascus just to say that the nursemaid drank a poisoned sleeping draught. It’s—’

She was sharp-witted enough to see the point of this at once. She looked from left to right, then held me by the arm and tugged me to one side. ‘You don’t think it was the rebels, after all? Then who . . . ?’ She looked into my face. ‘You’re not suggesting that she drank it knowingly?’

I said slowly, feeling for the truth, ‘It occurs to me that it is possible. That flask may be the so-called “sign” that she was looking for. It would explain why she begged us to let her back into the room, and why she wanted to have her two hands free, although she seemed perfectly happy to be chained.’

Priscilla took a moment to consider this. ‘I said that we should never have allowed her back upstairs!’ She sidestepped a ribbon-vendor who was proffering his tray and dropped her voice again. ‘But surely it’s more likely that a murderer exchanged the poison for her sleeping draught and she drank it by accident? The same person who kidnapped Lavinia earlier – and perhaps, who then climbed out of the room down that knotted cloth-rope which we thought the child had made?’

‘In that case,’ I said, ‘why throw the flask away?’ Now that I had realized the unlikelihood of that, I wondered why it had taken me so long to question it. ‘Yet she must have done. No one else could have got into the room last night: there was a slave outside the door, and Trullius and I watched with our own eyes as she pulled up the cloth-rope and undid the knots – making a pretence of examining each one – so there was no chance of anyone gaining access from the court. Besides, if a murderer had got into the room and forced the nurse to drink the poison he had brought, he wouldn’t have thrown a valuable jug away – especially where it was possible that it would be found, Surely he would have taken it with him when he went?’

The ribbon-man bobbed up beside us, offering his wares, but she waved him off as though he were a flea. She turned to me. ‘I see your reasoning. Rebels are always robbing people on the road to get hold of valuable things that they can sell.’ She frowned. ‘But what about the nurse?’

‘You don’t believe that she would kill herself?’

‘I can see she might want to do that!’ she replied. ‘Especially if – as now seems likely – she was party to the plot, either against the Vestal or against Lavinia. If her owners found that she was guilty of anything like that they’d have her put to death in ways that would make the poison seem an easy route. I can understand all that. But even if she took the potion willingly, the problem still remains: why throw the flask away?’

I had been asking the same question of myself. ‘Perhaps to make it look like sorcery,’ I said. ‘She was unlucky there. I have had dealings with an infusion of crushed hemlock once before. Otherwise I wouldn’t have recognized the stain on the drawstring of that purse – or identified the smell.’

‘And we’d have gone on thinking this was a Druid spell?’

‘Well, wouldn’t you?’ I asked.

She nodded thoughtfully and seemed about to speak, but the hopeful ribbon-man was back, bobbing up between us with his tray again. ‘Best ribbons, lady. All hand-dyed and woven by my wife.’

She turned on him. ‘I’ll hand-weave you, if you don’t move along!’ and he sidled off to hustle someone else. She gave me a knowing look. ‘And you had better move along with your donkey-boy as well, before some other customer appears who offers ready cash. But after what we’ve said, I think that I agree. I’ll simply send the message that the nurse is dead. If there are other explanations you can make them when you get back to Lavinius yourself.’ She made a wry face. ‘Perhaps it’s just as well. This way the nurse can have her funeral – if only with the guild – before her owners know that she was working for the Druids. Otherwise they might simply throw her body to the dogs, and then who knows what trouble we might have with her ghost. So I’ll go back and send that horseman with the message straight away, unless there is anything else you need me for?’

‘There is one thing that you can do for me, when you get back to the house. I think you said the nursemaid took Lavinia’s pot outside to empty on the midden-pile? Yesterday noontime, when she came down for the tray?’

‘That’s right.’ She looked surprised.

‘Then will you have your house-slaves search the rubbish pile for me? They’re looking for anything resembling a phial, or some container to put poison in. I still believe the hemlock mixture was carried into the bedroom in that pouch, and almost certainly not in that silver flask. If your slaves find anything unusual, have it put aside for me.’

‘With pleasure, citizen.’ Priscilla smiled. It struck me that – though she talked too much – she had a lively mind and now that her household was no longer under threat she was actually delighted to be asked to help. She beckoned to the donkey-boy, who had been lingering nearby. He came across at once. ‘Now see that you take this citizen the shortest way,’ she said to him. ‘If I find you’ve been taking detours, just to raise the fee, I’ll tell the magistrates – and I warn you this citizen has a wealthy patron, too, who knows how to make your life a misery. You understand?’

The boy looked sheepish but he said stubbornly, ‘I wasn’t going to cheat him. I’ll go the quickest way. But if he wants to get there for the fee that we arranged, we ought to go at once – give me a chance to earn some food today. I know you’ve promised to pay me later on – quite handsomely, I grant – but that’s all very well. I still need to eat and you can’t buy bread without real money in your hand. The baker doesn’t trade in promises. So, if you are quite ready, citizen?’

I signalled that I was and he set off at once, tugging his reluctant animal. There was nothing for it but to follow them. The donkey was a melancholy-looking specimen, all skin and ribs, and I feared it had the mange, so I consoled myself that perhaps it was as well that I was not to get my ride. But when we reached the eastern gateway to the town the urchin paused beside a mounting stone, and indicated that I should climb onto the creature’s back.

The only saddle was a patched and tattered rug, tied underneath the belly with a piece of hempen string. I climbed up, graceless and rather hesitant. I was accustomed to owning horses in my youth, but I scarcely went near one when I was a slave and it is many years since I have ridden anywhere.

This donkey was bony and bouncy compared to my fine steeds of long ago, and distinctly slow. But it was not displeasing to be on its back and although my toga billowed out and threatened to unwind, I very quickly got the hang of it. The donkey-boy was even more surprised than I was at my skill.

‘He seems to like you, citizen. Sit tight, and I’ll squeeze in ahead of you.’

I was certain that the donkey would refuse – it seemed recalcitrant in any case – but to my surprise it answered to the switch and we found ourselves swaying precariously along, not very quickly, but faster than on foot.

We must have presented a strange spectacle: a scruffy boy and a Celtic citizen with his toga half-undone, squashed together on a skinny donkey’s back. Certainly we did not go unremarked. Cart-drivers and riders who passed us on the way grinned and raised their whips in mock-salute and various land-labourers turned their heads to look.

The track – we had long ago turned off the Roman roads – swung uphill and down the valleys as the boy had said. In places it was barely wide enough to take a cart, but wheel-tracks in the mud were evidence that a wagon had indeed lurched past this way, and fairly recently. The presumed Paulinus and his wife were said to have a farm-cart, I recalled, and certainly the homesteads here were agricultural.

I began to wonder if my mission was a waste of time and this farmer and his family were not impostors, lured by the reading of the letter – as I’d thought – but exactly who they claimed to be, in which case all my careful reasoning fell apart and I had no other theory to advance. I would have liked to ask the donkey-boy about his previous mission to the farm, but he would have had to turn his head to catch my words, and such was the concentration required to stay on – particularly here, where the road was rough and steep – that there was really no opportunity for that.

At last the lad urged the creature to a stop, close to a clearing where there were several homesteads scratching a living from the land. ‘Here you are, citizen. This is the very place.’ He gestured with his switch.

I looked where he was pointing. Paulinus was a Roman citizen, from a patrician family and, although I had several times been told that he was not a wealthy man, I had expected something more like Lavinius’s estate, though on a smaller scale. This was a humble farm. The house was square and made of stone, as Roman dwellings generally are, and there was a land-slave working in the grounds outside, but there all resemblance to a normal villa ceased. There was no handsome court, no separate slave-quarters, no gatekeeper on watch inside imposing walls, just an enclosure made of piled-up stones, a single dwelling with a stable to the side and rows of turnips and cabbages behind, and a tiny orchard with chickens pecking free. There was a pig-byre just beyond the house, sharing a scruffy pasture with a cow and several piebald goats, while the entrance to the whole was guarded by a large dog on a chain. This was more on the scale of my own abode than anything more grand.

The donkey-boy was looking impatiently at me. ‘This is where I brought the letter, citizen, following the directions that were given me. Are you not getting down? I thought I was to leave you here, when I’d delivered you?’

I swung off my makeshift saddle, which swivelled under me and almost deposited me head-downwards on the ground. However, I managed to keep my balance and maintain my dignity, though I discovered that I ached in every limb. ‘And the man who lives here is called Paulinus?’ I said, with as much gravitas as I could muster.

He looked at me as though I were the donkey here. ‘That’s right, citizen. Or that’s what I was told. The letter was addressed to someone of that name, and when I brought it here, the slave I spoke to went and got him from the house and he came out personally and took it from my hands. Seemed very pleased to get it, from what I saw of him. Gave me a piece of bread and cheese for bringing it. Not the sort of greeting I usually expect, especially from proper citizens: generally they keep you waiting for an hour and then send a servant out to deal with you.’

‘So you’ll remember what he looks like?’ I said eagerly, glad to be making progress of a kind. If the description did not match what I had been told this morning by the slave trader, then the man who took the letter was not Paulinus.

‘Naturally, I do.’ The donkey-boy looked doubtfully at me. ‘You want me to describe him? It won’t be very flattering. He’s not a handsome man.’

I reassured him that he would not be punished for his words.

‘Well . . .’ The urchin dropped his voice, because the land-slave in the tattered tunic had come over to the pig and was feeding it something from a wooden pail, and it was possible that we could be overheard. ‘Tall and rather stooping, with a skinny face. Just a little balding, with protruding teeth. But he’s got a kindly smile, when he uses it. Took him a minute. Quiet voice as well. I thought he might be shy – if that’s not a silly thing to say about a Roman citizen.’

I was dumbfounded. The description matched exactly what I had already heard. ‘That is very helpful,’ I said untruthfully. ‘I’ll . . .’ But before I could complete the sentence the land-slave had looked up from his task and was calling out to us.

‘You have business with my master?’ He put down the pail and came over to the boundary wall, if you could call it that. The pile of stones at this point came no higher than his waist. His skin was tanned and wind-burned to an even darker brown than his coarse tunic and his leather boots, except where mud and grime had turned him to the greyish-black colour of his tousled hair.

‘I am looking for a man called Paulinus,’ I said. ‘I believe he was in Corinium yesterday.’

‘That will be my owner,’ he said cheerfully. ‘You’ve come to the right place. He went to Corinium all right – took some goods to sell and went to the slave-market while he was in town. What do you want with him? We don’t very often get visitors round here. Is there some trouble with a bargain that he struck?’

I shook my head. ‘There have been a couple of mysterious deaths,’ I said, choosing my words carefully. ‘Someone that he knew was set upon and killed, and a slave was found dead this morning at the very lodging-house where your master stayed. I’m hoping he can help me with my enquiries.’

The land-slave rubbed his filthy hands across his filthy hair. ‘I don’t mean any disrespect but, who are you, exactly, citizen?’

‘My patron is Marcus Aurelius Septimus,’ I said, but his expression told me that the name meant nothing here. I tried again. ‘I am sent here by the bridegroom of one Audelia, who was a Vestal Virgin until recently, and by her uncle who is called Lavinius.’

He grinned. His remaining teeth were crooked, but only one was black. ‘Oh, I see. We know all about Lavinius – he’s quite famous around here. Refused to help my master when he applied to him for aid. Wanted to take the child to a healing shrine. You know about the daughter of the house . . . ?’ He saw my nod and went on, more soberly, ‘Fortunately this new wife has got a kinder heart.’

‘And I suppose that your master was offended, too, by the fact that Lavinius did not ask him to the wedding feast?’

That jagged smile again. ‘On the contrary. Quite relieved, I think. My master never liked Lavinius very much and now that he has married for the second time, this household is too busy with its own affairs to spend the time and money that would be involved in travelling all the way to Glevum for a feast. In fact it is as well you came today. Another day or two and you would be too late. He and his wife are leaving here to take the child to Gaul – there is said to be a healing spring there, which they want to try. Not that I suppose it will do any good – nothing else has ever helped her in the least – but Secunda’s brought a dowry with her, so they can manage it, and if he wants to use her money in this way, I say good luck to them. Anyway, you never know, the spring might do the trick.’

I looked around. ‘And what about this farm, the slaves and everything? Surely they will not just abandon it?’

‘They’ve found a fellow down the road who will look after it in return for a half-share of the crops, till they get back again. Or, if they do decide to stay in Gaul, he’ll buy it as it stands – but I think they only mean to be away for a half a year. I hope so. I have worked here since a child, and you couldn’t ask for better owners. Both this wife and the first. I would hate to see a change. But if you want Paulinus – that’s him coming now.’

He gestured to where a tall, thin, stooping man – slightly balding and with protruding teeth – was hurrying towards us across the pasture-field.