But, disorganised and incomprehensible as they were, there were tens of thousands of them, Narcissus saw uneasily, perhaps even outnumbering the Roman forces. And at the rear of the crowd congregated by the river he saw horses drawing small, rapid, two-wheeled carts to and fro. They were the famous chariots of which Caesar had written so eloquently, rehearsing for war.

Vespasian showed no sign of unease. Indeed the legate seemed rather to be enjoying the spectacle. Vespasian pointed east, back the way they had come. 'You can see the native track we've been following,' he said.

The track had run parallel to the south bank of the estuary of the Tamesis, following a roughly straight line-not paved or properly constructed like a Roman road, but obviously ancient, heavily rutted and clearly useful. The army had made a thorough mess of its surface, leaving a band of churned earth that stretched off into the afternoon mist. But somewhere back there teams of road-builders laboured; the next force that came this way would make much faster progress.

'But,' Narcissus said, 'the track has led us to this fording place across the river.'

'Quite,' Vespasian said. 'The scouts say that the river here is an eighth of a mile wide. Not far downstream it widens-look, you can see-to perhaps twice that width. Further upstream it deepens quickly. So this ford is by far the easiest place to cross, and the British know it. This is the first significant obstacle we've faced since Rutupiae, the first pinch point where our formation is constrained. And so this is where the Britons have gathered to greet us. No doubt they intend to slaughter us one by one as we struggle across the ford.'

'But,' Narcissus said, 'the Britons know the land as we do not. Why make a stand at all? They could hide, harry us, try to starve us out.'

Narcissus shrugged. 'They've made some rather half-hearted attempts to do just that. But there doesn't seem a great deal of competence over there, secretary. We suspected as much from the moment we landed unopposed.'

'Unopposed save for a foolish boy who thought we were his friends,' Narcissus said, a little wistfully. 'Well, I imagine you have no intention of falling into the rather pathetic trap the Britons have set for you. What, then?'

Vespasian eyed him, almost mischievously. 'But that would spoil the fun! Do you really want to know how the plot will unfold even before the actors take the stage?'

Narcissus grumpily turned his horse's head, and led the way down towards the lower ground. 'Suit yourself. In the meantime I'm going to spend the rest of the day with Phoebus.' This was the most senior of the surgeons Aulus Plautius had brought with him-and, like most of the army's best doctors, he was Greek, like Narcissus. 'While you crack barbarian skulls, I may get some civilised conversation for a change. And perhaps I'll help stitch a few wounds or bathe a few broken heads. For I'm quite sure that for all your complacency, Vespasian, the Britons' iron blades will do some damage before this is over.'

Vespasian followed, apparently not offended. 'Yes, but we will prevail. Remember, Narcissus, that to these Britons all this is new. Even their leaders, the buzzing Catuvellaunian princes we hear so much about, have never engaged in a set-piece battle. We have been waging wars for centuries. We have preserved the wisdom of great generals like Scipio and Marius, Pompey and Caesar himself-we do not forget our victories, or our mistakes.'

'You are nothing if not systematic,' Narcissus said grudgingly.

Vespasian said, 'You're a hard man to amuse. Secretary, this may be the most significant engagement of the first phase of our campaign. It's hard to imagine the Britons raising such a force again, once we've scattered them. This is the battle of Britain! Aulus Plautius himself insists it is important for you to understand how this battle unfolds: you have the ear of the Emperor after all. Just watch, listen, remember-and tell Claudius what a good job we did for him today.'

Nectovelin stalked through the Catuvellaunian camp on the bank of the Cantiaci River, with Agrippina and Cunedda at his side. The three of them were looking for Caratacus and Togodumnus. Nectovelin hoped to find out what, if any, strategy the princes had in mind. They weren't having much luck. The place was in chaos.

The warriors themselves looked imposing enough. Both Nectovelin and Cunedda, dressed for the fight themselves, wore armour: sword belts, chain mail, leather trousers, iron helmets, and big rectangular shields. Nectovelin's shield was especially handsome, with bronze inlays of angry boars over hardened wood, and it bore the scars of multiple axe blows. Cunedda was tense, though, fingering the hilt of his sword. He had no experience of war, but, he said, honour would not allow him to shirk the fight today. Other warriors worked on their weapons and armour, fixing holes in their chain mail vests, grinding the edges of their swords.

But many of the would-be fighters wore only farmers' work clothes, tunics and trousers and cloaks of wool or leather, and had no weapons save for a club or a scythe.

Agrippina admitted that a good crowd swarmed on this muddy river bank. Caratacus's army was made up of levies from the Catuvellaunians themselves and from the peoples who owed the Catuvellaunians tribute, mostly Trinovantes, Cantiaci, Iceni and Atrebates. Nectovelin constantly grumbled that the disunity of the British nations since Cassivellaunus gave the Romans their clearest advantage. Even before the invasion force had landed some southern rulers had allowed Roman soldiers on their territories, making them protectorates of the empire. So it was a significant feat of leadership for the Catuvellaunian princes even to have assembled this horde of many nations, though Nectovelin growled ominously that he could see no sign of the Dobunni's promised warriors. But it was a scramble, a mix-up, a crowd of many tongues, and it was hard to see who was in charge.

And the fighters had brought their families, even their dogs and goats and sheep. Children swarmed around Agrippina's feet, mock-fighting with bits of wood, excited by the noise. Vendors of broiled meat, pine cones and hazelnuts worked the crowd. With the noise of men shouting, children screaming, dogs barking and chickens clucking, it was more like a huge, disorganised market than an army.

This was the way the Catuvellaunians and their allies and enemies had always fought their wars. But Agrippina glanced uneasily across the river, where the clean straight lines of the legionaries' fort were clearly visible.

Cunedda asked Nectovelin, 'So what do you think?'

Nectovelin grunted. 'What a dog-fight. I wouldn't bring my family here, put it that way.'

'I'm your family,' Agrippina pointed out.

'Yes, and I had to stop you putting on armour!'

'There are many women preparing to fight here-Braint among them.'

'Braint is a tough old boot with forearms like Coventina's shuddering thighs.'

'I heard that,' Braint growled, suddenly right behind them. Agrippina was always surprised such a massive woman could move so silently.

Nectovelin sighed. 'My point is, 'Pina, she will make the Romans piss their pants-whereas you, child, would only make them laugh, before they performed revolting acts on you and slit your throat. I have a feeling you'll get your chance for revenge,' he said grimly. 'But not today, not here. Not like this.'

'You're looking for Caratacus,' Braint said.

'Since the sun was high.'

'The princes are at the edge of the water. Follow me.'

Nectovelin and Braint led the way down to the river. The ground here, already marshy, was churned up by feet and hooves, and was thick with animal droppings. They had to work their way through hastily assembled defences: heaps of boulders, trenches, stakes thrust into the ground, all intended to deter the anticipated Roman crossing. The crowds grew denser until Agrippina was hemmed in on all sides, and the noise and stink of leather and sweat grew overwhelming. It took some heavy shouldering by Nectovelin and Braint to force a way through.