But Stef was sure no Roman of the ‘old’ history she knew had ever seen a sight like the one she glimpsed on the far side of this fifth deck, as a squad of legionaries under the control of a hovering tribune struggled to fold up the squirming hull of a deflated cetus airship.

Titus gathered the newcomers together. He was carrying the ColU in its pack, handling it as tenderly as a baby, Stef observed. ‘Come on. Soldiers’ business on this deck. You’re in the civilian town, next one up.’ Grabbing a rope, with the pack around his neck, he pulled himself one-handed away from the docking port, and headed up to the ceiling.

Stef and Yuri glanced at each other, shrugged, and followed. Stef made sure she let Yuri go first, unsure how strong he’d be feeling today, but he seemed to be moving freely enough. Maybe a lack of gravity for a while would be good for him. As she climbed she called up after Titus, ‘Why are you carrying the ColU? What about Chu?’

‘He’ll be taken straight to the third deck.’

She remembered. The slave pen, Titus had called it, above the farm, below the barracks.

‘Slaves are stupid creatures and more so without gravity. They flap around uselessly and puke everywhere. They’re best strapped down for the duration. You won’t see Chu until we’re under way and we get stuff properly sorted out on board.’

She was in no position to argue.

They passed easily through an open port up to the sixth deck – open, but Stef noticed there was a heavy iron hatch on hinges over the port. She imagined whole decks of this vessel needing to be locked down in case of some disaster, a blowout perhaps – or even in case of a rebellion by disaffected soldiers, or the slaves in their below-decks pens.

As they swam up, following more ropes, Stef wasn’t surprised to find that on this deck, which Titus had curtly labelled the ‘town’, was indeed a small town of the Roman type, or at least a section of one, like a walled-off suburb. Rising easily into the air above tiled rooftops, she glimpsed a grid layout of streets centred on an open space, a forum perhaps, surrounded by multi-storey porticoes and with a small triumphal arch at one edge. Built up against one section of hull wall were banks of seats over an open space, a kind of open-air theatre. And around the circuit of the hull walls ran a track, she guessed for racing or other sports. Everywhere people swarmed in the air: men, women, children, hovering over the buildings and ducking down into crowded streets. The noise in this enclosed space, and echoing off yet another roof-partition above, was tremendous, a clamour of voices that sounded like a sports crowd.

Stef felt overwhelmed by the sheer vivacity of it all, the complexity, and she realised how little she’d seen of this mobile community down on the planet – and now here it was, cramming itself back into this tin can in space for the five-year journey home. But, even more so than on the military camp deck below, she smelled the sour stink of weightlessness-sickness vomit, and laced in with the general noise she heard the wail of infants. Any children under three must have been born on the planet itself, she realised, and they must be utterly bewildered by the environment of the ship.

With effortless skill, impressive given he had only one hand to use, Titus led them down through a lacing of guide ropes to a neighbourhood a block away from the forum. ‘You’ve been assigned a house down there. Not a bad district, there’s a decent food shop and a tavern. You’ll need to sign in with a councillor, he’ll find you, and the optio will come and check on you before the engine fire-up  … Any questions?’

Yuri asked, ‘Why do you put tiles on the roofs? We’re inside a spaceship.’

Titus shrugged. ‘It does “rain” in here sometimes. You have to cleanse the air of dust. And besides it’s tradition to have tiles on your roof. We Romans don’t live like animals, you know.’

Stef said, ‘I can’t get over how big all this is. How many people aboard, Titus, do you know?’

‘Well, the core of it is us, a century of the Legio XC. Eighty men give or take. But then you’ve got the officers and the staff and the auxiliaries, and then you’ve got our wives and families, and then you’ve got the merchants and cooks and artisans, and doctors and schoolteachers and such. Oh, and there’s the ship’s crew, mostly Brikanti, or Arab. What have I forgotten?’

‘The slaves?’

‘Oh, yes, the slaves,’ Titus said. ‘As many of them as there are soldiers and other citizens. I’d say five, six hundred warm bodies on the ship.’

‘That’s a lot of people.’

‘But it’s the Roman way. You can’t do it much smaller than that, miss.’

‘Quite,’ said the ColU. ‘And that’s why the ship itself has to be so big. Stef Kalinski, we know these people have no grasp of fine engineering. Small-scale closed life support systems would be beyond their capability. So they build big! They bring along a massive volume of air and water – you said there was a whole deck devoted to farming, Titus?’

‘Yes. A lot of greenery up on the villas deck too.’

‘They build so big that this ecology is reasonably buffered, stable against blooms and collapses, despite the crudeness of the technology. It’s all logical, in its way.’

Yuri said, ‘So when will they fire up the kernels, Titus?’

The big man grinned. ‘Six hours. You want to be lying flat when they sound the horn. And believe me, you want to be indoors. It’s not like the camp here. No discipline. Nobody listens to the warnings. There’ll be a sky full of babies and their shit, suspended overhead. You do not want to get caught in that rain when it falls. Come on, your residence is just below, I’ll get you settled …’

Stef thought they descended like angels into the street where they would live for the next five years.

Six hours later, right on cue and accompanied by trumpet blasts, the banks of kernels at the base of the craft fired up. Stef imagined arrays of the enigmatic wormholes being prodded open to release their energies, streams of high-energy radiation and high-velocity particles, morsels of thrust pushing ever harder at the huge, ungainly structure of the Malleus Jesu.

As the acceleration built up, Stef, sitting with Yuri and the ColU in deep couches in the small house to which they’d been assigned – surrounded by plaster walls with crudely painted frescoes – heard cracks and pops and bangs as the giant frame absorbed the stress, the rattle of a tile falling from a roof. She imagined the ship’s basic structure would be sound: it was built of good Scand steel, Eilidh had assured her, not your Roman rubbish. But even so, after three years in microgravity – three years of neglect, as everybody was busy on the surface of the planet – there would be point failures, breakages of pipes and cables. Now there were shouts and distant alarm horns as, she imagined, emergency teams dealt with various local calamities. She even heard a rushing collapse, like an ocean wave breaking, as, perhaps, some small building fell in on itself.

Then there were the people. As she and Yuri sat in the semi-gloom – no oil lamps could be lit during the fire-up, that was the rule – and as the weight built up and pressed her into her chair, all around her on this deck with its model-railway toy town, she heard cries and groans, the clucking of distressed chickens, the barking of confused dogs, and the crying of children.

Five years of this, Stef thought. She closed her eyes and tried to relax as the acceleration pressed down on her.

CHAPTER 13

A week after the fire-up, Stef broke a tooth.

In this most exotic of environments, a starship run by a Roman legion, it was the most mundane of accidents, caused by biting down on a slab of coarse Roman bread. She knew by now something about the tumours that riddled Yuri’s body, detectable by the ColU but untreatable by it without the medical suite in the physical body it had left behind on Per Ardua. Yuri hadn’t wanted to tell her; she’d forced it out of Michael, the kindly physician. Compared to Yuri’s problems, this was nothing.