Before they bundled up under their blankets and clothing heaps to sleep, huddling together under Beth’s stretched-out tent, Titus came around one more time, accompanied by Clodia with a simple medical pack. The legionary insisted on checking everybody’s feet, for bruises, chafing, incipient blisters. ‘Now that you’re all soldiers on the march you’ll learn that your most important items of equipment are your feet. Look after them and the rest follows. And the sooner you’re all capable of doing this for yourselves, the better.’

‘Goodnight, Titus Valerius.’

‘Goodnight, auxiliaries …’

And, after Titus had done his round, Stef heard rustling, saw shadows slip through the dim light under the canopy. They were unmistakable: Chu Yuen and Mardina Eden Jones Guthfrithson, clutching blankets, hand in hand, making their way out from under the canopy and into the shade of the forest.

The next day they made better progress. And the day after that, better still.

Stef made a deliberate effort not to count the days, not even to try to estimate the distance travelled. She knew she could leave that kind of management to Titus and the ColU. And besides, she slept better if she tried not to think about the monumental journey ahead. She thought of this as a new way of life, a long tunnel of routine that was going to fill her days for the foreseeable future. Sleep, break camp, march, make camp, sleep … Without beginning, and without end.

But, gradually, the country began to change.

They descended from the substellar high ground, and the haulers began to lose the benefit of the downward slopes Titus had cunningly scouted for them. On the other hand the weather on the lower ground, away from the permanent low-pressure system over the substellar point, became milder, less turbulent. Day by day there was less wind and rain. And the vegetation around them responded. Now the broken forest that characterised the relatively unsettled substellar gave way to more open country, with forest clumps separated by broad swathes of ground-hugging, light-trapping vegetation.

During the long hours between the days’ marches, the ColU had Chu carry it out into the country away from the camp to inspect the changing terrain. Out of curiosity, and when she had the strength, Stef followed them – often with Beth, who was curious to see more of what had become of this world that she still thought of as home.

At the end of one unremarkable day, they walked side by side over a plain almost covered in sprawling green leaves, like tremendous lilies, Stef thought. Systems of three leaves united at a central stem, covering the ground, and basking in Proxima light. When she knelt down to look closer she saw that the leaves were firmly anchored to the ground by fine tendrils, covering every square centimetre. No competitor was going to swipe this plant’s growing space, this share of the starlight. It was a very Arduan scene. But when she dug her hand into the ground beneath one leaf, she came up with what looked like an authentic sample of terrestrial soil, complete with an earthworm, a thing like a woodlouse, and other creeping terrestrial creatures.

As they walked back to camp, Stef gradually got a broader sense of the wider landscape. With the star static overhead, and every square centimetre of ground colonised thickly by the green of life, this part of the world was like a huge, collective, cooperative system, optimised over time to extract every scrap of energy from the light falling from the sky. Stef felt as if she was in some vast greenhouse, old and decayed, the glass choked by lichen, moss and weeds – with here and there a vivid splash of Earth life embedded in the rest.

In the middle of the next day they came to the bank of a river, wide, placid.

Stef clambered off her bench and hobbled over to Titus. He was standing with his one good hand on his hip, staring out at the water, grinning. ‘This is as far as I came with Clodia, during our scouting trip. Well, I judged we need come no further. This river clearly flows out of the substellar point—’ and he waved his hand back in the direction of Proxima ‘—and, no doubt fed by many tributaries, continues to flow in a roughly south-easterly direction. Well, you can see that. Now, Stef, tell me I’m no surveyor. Madam, I present a highway as straight and true as any Roman road. And now, for a time at least, we can all ride in comfort, as you have been all the way from our first camp.’

‘Aye aye, cap’n.’

‘I beg your pardon?’

‘I imagine that didn’t translate …’

They made camp in the usual manner. Then they got to work reassembling their cart into a small boat – detaching the wheels and axles, going over the seals with their marrow caulking, and digging out paddles they’d crudely made from dead stems lashed up with rope.

In the breaks they took advantage of the river, washing their feet and clothes, dunking their whole bodies luxuriously in water that ran refreshingly cool. But Titus banned any swimming. Though the river ran with a strong current, it was obvious that the bed was choked with life, and he didn’t want anybody getting caught up in that.

It took them forty-eight hours before they were ready to embark. After so long on the road, many days already, they had all learned not to rush.

As with their first day’s walk, Titus decreed that their first jaunt in the boat would be a short one, to ensure they ironed out any flaws. He made sure that those to whom he entrusted the paddles had fabric wrapped around their palms for protection, and ponchos improvised from lightweight survival blankets to keep off the spray. They even had to wear their light camp sandals, so that their boots, precious items of equipment, could be bundled in waterproofs. It was all detail with Titus, Stef observed.

It visibly infuriated Titus that, lacking an arm, he couldn’t manage a paddle himself. But he insisted on riding at the stern, where a crude rudder had been attached.

Once they were all loaded aboard, their stuff lashed down, Chu shoved them off from the bank with a mighty jab of his paddle against a rock, and they drifted out towards the centre of the river. Titus was at the stern with his rudder, Stef at the prow with her back to the river. Of the four rowers, Chu and Clodia sat together to Stef’s right, and Beth and Mardina, mother and daughter, to her left. For the first couple of miles they were all silent, save for Titus’s curt commands: ‘That’s it, we’ll keep to the centre where it’s deepest … Paddle a bit less vigorously, Chu and Clodia, you’re too strong and you’re shoving us to the bank, we’ll balance you up better when we stop … That’s it … If we can let the current take the boat away without us having to do any work at all, I’ll be happy …’

Stef found herself anxiously watching the deck under her feet, looking for leaks. She had crossed interstellar space in kernel-drive starships, and had even walked between realities through a technology that was entirely alien. And yet a ride in this ramshackle craft, with just a few metres of water beneath her, was somehow more terrifying than all of that.

But they hadn’t gone far before she was distracted by the atmosphere in the boat itself. Mardina glared at Chu and Clodia, and Clodia glared back.

‘Ouch,’ Stef said at length. ‘I never heard a silence so loud. What the hell’s the matter?’ But of course she anticipated the reply.

‘Her,’ Mardina burst out, pointing a finger at Clodia.

Clodia looked ready to leap across the boat and take her rival on.

‘Sit still,’ Titus commanded his daughter. ‘Wield your oar. You too, Mardina. Snarl at each other if you must but you will not imperil this vessel … What’s this about?’

Clodia glared. ‘Do you really not understand, Father?’

Titus sighed. ‘Being not entirely without senses – yes, Mardina, Chu, I’ve seen you two sneaking off in the night.’