Valens grabbed a second brand and, without waiting for the others to get to work, urged Rigonorix out of the door. Outside, he pointed left. ‘Quick as you can, just the easy burns and then get back to the Redoubt. I’m not keen on our chances, but I think they might be lower without you.’

As the fugitive ran off, Valens turned in the other direction. Rigonorix had the smaller side of the fort with only six short blocks, and would easily be able to identify those that would burn quick. Valens’s side, to the south of the redoubt, also consisted of six blocks, but these were each twice as long. Running around to the furthest one, the optio ran down the street between them, looking into each doorway briefly as he passed to determine at a glance whether it was in use or an empty and abandoned block. Those he found that were being used he dipped inside, found cheap drapes at the window or straw-stuffed sleeping pallets or suchlike and swiftly thrust his burning torch into them until they burst into flame, hurrying out as smoke began to fill the room.

By the time he reached the main cut-through street, he could see the last of the men from the south Wall hurrying along it, pulling back to the redoubt. Damn it, but he’d thought he had more time. The next block was the partially demolished one that had gone to helping construct the redoubt and he hurried past, heading for the next door, nodding as he passed at Belliacus, who formed the rearguard of the retreat.

The aging cavalry veteran, realising what Valens was about and with a swift backward look at the walls that would be surged over at any moment, reached for a rake that stood in the wreckage and dashed across to the optio’s latest victim, from whose windows smoke already belched. Hooking the rake into closed shutters, he lifted it to a shaky-looking lintel and heaved. Valens was impressed at the surprising strength in such an old man as the wall creaked and holes opened in it, smoke billowing out from the cracks. The optio was still watching as he moved to the next door, and so he saw the reward for Belliacus’s efforts. The end of the block collapsed with a crash, the old man dancing quickly out of the way, dropping the rake and resuming his retreat. The burning building slid out into the street, blocking it to any enemies that might cross the wall and follow. Good man.

Valens torched the last door in the street, then dashed around the end of the block and into the next street, running back up it and repeating the process. By the time he was back at the centre of the fort, outside the headquarters building and the door that allowed access to the redoubt, the forge had been abandoned and torched, and this entire side of the fort was ablaze, smoke billowing and filling the streets, a terrible obstacle for any potential assault.

Rigonorix rounded the end of the building and ran up to join him, covered in soot and blood.

‘That should buy you and hour or two, with luck.’

Moments later Valens, with Rigonorix in tow, emerged into the courtyard of the headquarters building. Not everyone was gathered here, for men were still hurrying to build up the defences of this now-critical redoubt, but most were present. Valens pushed down his fears and despair. What everyone needed now was hope.

‘Congratulations on an impressive defence, given our numbers. We’ve already shown them that Rome is not easy to simply roll across. You will undoubtedly be wanting to know what the plan is.’ He took a deep breath. Plan? Ha! ‘Simply, we hold out as long as we can. Sounds poor, I know, but there are a limited number of them and though they outnumber us, we are making them pay heavily for every advance they make. Every enemy has a breaking point. All we have to do is get them to the point where it’s cost too much and their goal no longer seems worth it and they’ll go away. We hold this redoubt and kill as many as we can.’

He looked around. ‘We have between one and two hours at best guess until the timber buildings of the fort burn down, and even then the stone footings will be too hot to touch for a while. We need to use that time. All soldiers and civilians should take the chance to have an hour’s uninterrupted sleep. There are six beds in the commander’s house, and various shelves, tables and benches. We’ve plenty of blankets. I’m going to split everyone into groups and I want half of each group resting at any given time.’

He took a deep breath. ‘Five groups. One is civvies, working on supplies and moving ammunition around. That’s Lugracus the smith’s group, and he’s in charge. Lugracus, you know what you need to do, I’m sure. Optio Secundus? You’re from Alauna, and Alauna has been rebuilt in recent years, so you know your fortification, I reckon. You lead the group finishing off the defences of the redoubt.’

He looked across at the man, whose lip wrinkled in irritation at being dictated to, but the logic of it broke him, and he nodded his understanding. Valens looked this way and that.

‘The commander’s house will be our barracks and hospital. It has no external windows or doors, but I want one group manning the redoubt walls between this building and that and controlling the roof of the place. That’s Belliacus’s section and Fulvius’s medic station will be your responsibility.’ The veteran nodded his consent.

‘And at the far side, the granaries will be our stores and production centre. The smith and his people will be working in there.’ He prepared himself for the inevitable trouble. ‘Rigonorix is in charge of defending it, the roof and the walls.’ He looked across as Secundus shot to his feet angrily. ‘No, Optio. This is my command and your prisoner, no matter what he’s done, is the right man for the job.’ Even as Secundus argued, Valens spoke louder over the top of him. ‘I will take the centre. The wings are most vulnerable, so I want to leave this one main door open for now and to create a half-moon redoubt out of grain bags outside it to draw their attention. Let’s make them fight on our terms. All we need is to keep them here.’ He geared up for the lie. ‘We only saw one runner from the north gate die. Cestius may have lived. I wouldn’t put it past the weird, wily bastard. I think he got away. That means he’s running for help from Glannoventa. So even if we can’t make the natives give up, we only have to hold until reinforcements come.’

There was a subdued murmur of hope at this, and Valens waved a hand. ‘I’ll be dividing you into the teams in a moment.’ He then crossed to a corner and faced away from everyone so that he could allow the despair to show, then took a breath and turned, only to find Rigonorix beside him.

‘You know that’s bullshit, right?’

‘What?’

‘It’s been less than three hours since the start. Even if your man is godlike in his speed, he still won’t even have reached Glannoventa yet and there’s not a dog in Hades’ chance he’ll get back with reinforcements in time. When they get here, we’ll only exist from the neck up, all on pointy sticks.’

Valens nodded. ‘Do me a favour, and don’t tell anyone else that.’

Rigonorix gave Valens a tight nod of agreement and then waited as the optio moved around the room, identifying civilians and soldiers and assigning them a role. The last was Hermod, all others present assigned a place. Valens gestured for the huntsman to follow him and stepped out through the temporary doorway that had been hacked through an office wall to allow for swift access from the principia to the newly-walled area between there and the granaries. There, they hurried over to the south wall that had been built across the road with rubble and timbers. A fighting platform behind it was formed from benches, tables and crates.

‘Think you can get up onto the principia roof from there?’

Hermod looked to the platform, the wall, the roof, and scratched his head. ‘I figure so. Why?’

‘We need someone on watch to warn us when they start to move into the fort. It strikes me that that man would be useful if his viewpoint was also a good place to loose arrows from. Think you can do it? Keep watch and then pick off some of the bastards as they come?’

Hermod sucked cold air in through insufficient teeth, and clambered up to the fighting platform, from there onto the wall, and then onto the low-pitched tile roof of the principia. There, he scrambled up the tiles until he reached the apex. ‘This is no good,’ he called down, then scrambled back down and dropped into the space behind the wall again.

‘Why?’

‘Not clear enough. Between this roof being roughly the same height as the burning buildings and the smoke everywhere they’ll be almost here before I can see them. I’ll be better off in the northeast corner tower.’

Valens stared at him. ‘That is also suicidally insane. The moment they get through the walls you’ll be trapped.’

‘And so will you, just in a different place.’

‘Hermod, we can’t protect you there.’

The hunter gave him a hard look. ‘Tell me my chances if I stay here.’

The optio choked on his reply for a moment. ‘I’d be lying if I said they were good.’

‘Precisely. From that tower I should be able to see the whole fort, and given that they know you’ve pulled back to the redoubt they won’t be looking for anyone in the towers. With the smoke and the chaos, I can probably drop a dozen men without them working out where the arrows are coming from. As soon as I see anyone cross the threshold into the fort, I’ll drop an arrow into the principia courtyard. That’ll be your warning.’

‘You’re sure you can do it?’

Hermod gave him a withering look. ‘It’s eighty paces. I could put it through your foot at that range if I wanted.’

‘And what will you do when they’re swarming us at the redoubt?’

‘Drop down the outside and slip away into the snow. No one knows the hillsides and valleys around here like me, Valens.’

The optio looked at him steadily for a while and then finally nodded. ‘Far be it from me to condemn a civilian if he stands a chance of surviving this. Just try and remember to drop us a warning shot before you run. Oh, and try not to put it through my foot, however tempting that might be.’

Leaving the huntsman to his work, confident that the man could deliver adequate warning and would do his duty by them before melting into the landscape, Valens ducked back into the main room. The man who’d been working on the stores listing was hefting a sack and looking urgently at Rubellius, who was shrugging irritably. Spotting Valens, they both hurried over.

‘What is it?’

‘Lugracus gave me a sack of caltrops. I don’t know what to do with them.’

‘Melt them down and make something useful,’ grunted the bulky legionary beside him.

‘No,’ the optio said. ‘I told him to finish them. They’ll be useful.’

‘Not as useful as a real weapon, sir,’ Rubellius murmured.

Valens fixed him with a hard look. ‘Have you ever tried running and climbing a wall with an inch of iron through your foot? You’ve got caltrop duty. I want you two to get up onto the rooftops and scatter those all around the redoubt in the streets.’ The two men saluted, and Valens pointed at the smaller man. ‘Were all six scorpions brought in?’

The man frowned. ‘I’ve only seen four sir.’

The optio cursed. ‘The ones on the northern corner towers are still there. Damn it. Get the four we have set up at each of the four new redoubt walls. I’m going to get the other two. Can’t leave them there in case the enemy can work them. Do me a favour and wait til we’re back to scatter your caltrops on the route to the corner towers.’

Turning, he spotted Pollio, lurking in a corner, shirking as always. Grabbing him by the shoulder,  Valens propelled him out of the main door. ‘Run to the tall tower – the northeast – and grab the scorpion. You’ll find Hermod there, but just leave him to it. Heave the bloody thing over your shoulder and bring it back here.’

Pollio’s brow creased. ‘That’s a two man job, sir. They weigh a ton.’

‘Well I’ve noticed how often you’re mysteriously on sick when it’s time for heavy pack training marches, so you’re overdue, and if I can carry one you can carry the other. I’m getting the one from the northwest.’

Pollio gave him a sour look and saluted, facing both a direct order and unbeatable logic.

‘Be quick,’ Valens urged him.

‘Fucking right, boss.’

The two men ducked out of the door, hurdled the burgeoning apsidal sandbag defence outside and split up. Leaving Pollio to it, Valens ran west through the choking black clouds in the street. At the far end, he dipped around the end of the commander’s house and ran for the wall steps. Slipping here and there on one of the as-yet unswept sections, he tottered along the wall to the tower. Belliacus had issued the order to pull back to the redoubt upon hearing Valens’s signal, but he’d not known about the two scorpions on the northern side, and without support and lacking ammunition anyway, the soldiers manning them had left them.

He found the torsion weapon standing on the turret top and lifted it, groaning at the weight. Pollio had a point. For a moment, he considered just cutting the cables to render it useless, but decided against that. He might yet need six. Heaving it up with difficulty, he turned to leave, and paused.

Outside the fort, the enemy stood silent in a ring, all around, waiting for the fire to die down. They were in no rush. Valens swallowed his nerves and looked up as something brushed his nose. The snow was starting again. Wonderful. The thrum of a released arrow dragged his attention back and he ducked and staggered for the stairs with the heavy weapon.

The last thing Valens had expected was to be under attack during what he’d assumed to be a lull. With the enemy holding back beyond the walls and waiting to attack when the fort was clear, he’d felt he could rely upon being safe inside the fort to prepare. Clearly that was not the case. As he dropped into the stairwell and staggered down the steps under the tortuous weight of the scorpio, arrows and sling stones clattered and clacked off the battlements. Out of their sight for now he breathed deeply, lugging the heavy artillery piece down the steps. Normally they were moved on carts during campaigns and even when moved into firing position it was the job of two men. Valens struggled with it and felt guilty that he’d lumbered Pollio with the other. The man was, according the manual at least, too reedy, light and short for a proper soldier. Carrying one of these would be a bloody nightmare for him. Should have sent Rubellius and left Pollio scattering caltrops really, but the little bastard had wound him up.

The uneven terrain on which the fort was built, combined with the peculiar mindset of the legion that had built it, had resulted in towers that had no doorways at ground level, all merely opening onto the walls. It was unusual, and had probably saved the legion a bunch of time and planning, but right now it left Valens in the shit.

He could not go down to the lowest level of the tower, as it was just storage and had no external door. He was forced to drop down just one level and emerge onto the wall top and, though he immediately ducked as low as he could, given the hefty burden he lugged along a fresh barrage of missiles launched up from the crowd outside, clacking against the parapet as he dashed along it. One in particular severed the feather that jutted from his helmet above the ear, a badge of rank, in passing. By the time he reached the nearest wall stair, he was wild-eyed and praying to every god he’d ever heard of, including the local ones this lot worshipped.

He almost threw himself down the stairs, and narrowly avoided ending up in a heap at the bottom with the weapon on top of him. Struggling to pick it up in rapidly numbing fingers, he raced back to the redoubt formed of the central three buildings. The snow was becoming thicker again by the heartbeat now, and he tried not to think on what that meant. He failed. The increasing snow would put the fires out all too soon, cutting down their desperately needed period of safety. As soon as the blizzard doused the fires, the Carvetii would come again.

He cursed as he rounded the western end of the commander’s house and his foot sent a thrill of white hot pain up to his brain. He stopped and looked down in shock. Caltrops lay scattered around the street. Snarling angrily, and grateful that he’d only grazed his instep rather than impaling his foot, he promised himself that he’d jam that appendage a good distance up Rubellius’s arse when he got inside.