‘I don’t understand. What would the Sapa Inca want with me?’

‘You would be treated very well – like an Inca, or his heir, yourself. You would see Hanan Cuzco! You would eat the finest food, drink the finest beers—’

Mardina saw it. ‘She would be killed,’ she said. ‘That’s the capacocha, isn’t it? The sacrifice of children.’

He spread his hands. ‘It is the ancient way. You would be preserved … Your beauty would never be lost, or forgotten.’

‘And this is what you saved me from.’ Clodia sounded more bewildered than scared. ‘Why?’

Now Mardina scowled. ‘If you’re expecting some kind of payment in return for this, apu—’

He seemed hurt by the suggestion. ‘Oh, it’s nothing like that.’ He looked at Clodia sadly. ‘I have a variety of motives. One is simple pity. You are so young, and so new to this world. It seems wrong to snatch you out of it so suddenly! And then there is Inguill.’

‘The quipucamayoc?’ Mardina asked. ‘What does she have to do with it?’

‘She doesn’t want you Romans … disturbed. Not yet. She doesn’t want you rising up in rebellion, for instance, because we took your prettiest child.’

‘Why not?’

‘Well, she hasn’t told me. And probably for reasons you would not yet understand. But I don’t believe she’s finished with you yet.’ He fished a watch out of his pocket, a crude affair of knotted string and steel springs. ‘Still not safe for you up there. Would you like some more water?’

CHAPTER 48

It took some weeks, carefully counted out by Beth in the unchanging light of Proxima, for Earthshine to make himself ready for the journey to the antistellar.

Beth packed up too, in the end. She decided she would accompany him for at least some of the route he had picked out for himself – a route based, he said, on maps of the Per Ardua she had known, and which he hoped would still have some usefulness here, wherever here actually was.

But she always intended to come back, alone if need be, back to the substellar, and the starshine. She’d be able to retrace her steps, she was sure of that. And her own gear, the shelter and other survival gear, even her Mars pressure suit, were light enough for her to carry, unaided by the support unit. After all, the substellar was surely as comfortable a location to live as she’d find anywhere on the planet. And if anybody else showed up on this world – well, they’d probably make their way to the substellar as the most obvious geographical meeting point, even if they didn’t just come through the substellar Hatch in the first place.

Earthshine did have his support unit complete a survey of the substellar site before they left, purely for completeness, Beth thought. The unit sampled the soil for traces of metals or other exotic materials, and ran sonar and geophysical surveys of the area in search of deeper traces of habitation.

And, after an unpromising start, it found something. Though the surface layers were bare of artefacts or structure, there was scarring in the bedrock, traces of deep foundations, large underground chambers cut into the rock and long since collapsed. All this was buried under more recent layers of gravel and soil.

Earthshine showed her the results on a slate. ‘Look at the design,’ he said. ‘The architecture, what you can make out of it. We, from the UN-China continuity, built in circles, rectangles …’

The buried remains were more like overlapping ellipses, Beth thought, connected by curving threads of long-imploded corridors.

‘Once there must have been a considerable community here. Of course they would come here to the substellar; everybody comes here. It’s all gone from above ground, any toxins or radioactive debris or the like long washed away, the remnant building stone shattered to dust by the weather. But it would take an ice age to scrub away these relics in the bedrock. And Per Ardua doesn’t have ice ages, not the way Earth does, with glaciers and ice caps grinding their way across the landscape.’

‘These traces could be very ancient, then.’

‘Unimaginably,’ Earthshine said heavily.

‘Then they can’t be human.’

‘Why not? Humans have been here, surely, whatever the distortion of history. You pointed out that somebody must have brought the potatoes.’

‘Yes, but people first got to Per Ardua only a few years before I was born.’

‘That was in the old continuity, in the UN-China history.’ He glanced up at Proxima. ‘And you’re assuming we travelled sideways in time, so to speak, as well as across space.’

Sideways in time? She asked him what he meant by that, but he wouldn’t elaborate.

After that, Earthshine turned his back on the substellar. It was clear he wasn’t interested in human endeavour here, however enigmatic or ancient. All he cared about was his ongoing dialogue, or undeclared war, with the beings he called the Dreamers.

And to pursue that, he had to get to the antistellar. That was his obsession, and nothing was to be allowed to distract him.

When they departed at last, Beth left behind a note, pinned under a rock on top of the Hatch emplacement. Just her name, the date they’d arrived here in various forms of calendar, and an indication of where they’d gone. You never knew what, or who, might turn up.

And so they marched, heading roughly south-west. Earthshine said they were mirroring a farside journey made by her own father with Stef Kalinski long ago, before they had disappeared into a Hatch they had found at the antistellar.

Earthshine walked tirelessly, of course, and as he had offered they had rigged up a seat for Beth to ride on the support unit. But she mostly refused to use it. She wanted the exercise; she wanted to toughen herself up. If she was in for a solitary life on Per Ardua it would pay to be in good condition. And also she didn’t want to get carried too far and too fast; she wanted to stay inside a reasonable walk-back limit as long as she could. So she walked, though Earthshine displayed a very authentic-seeming impatience to make faster progress.

At first they followed the valley of a river, flowing radially away from that central point. Per Ardua’s basic climate cycle was that water that had evaporated from across the hemisphere was drawn into the substellar low, rained out there, and then returned to the wider landscapes via rivers like this one. An additional cycle worked at the terminator, the band of shadow that separated the day side from the night; more rain fell from the cooling air there, to spill back towards the warmth of the starlit side.

And as they moved out from the substellar point, following the river, the landscape gradually changed. The substellar itself was at the summit of a tremendous blister of raised land, a frozen rocky tide lifted by Proxima, directly above. Per Ardua was in fact egg-shaped, if only subtly, as the tide raised a similar bulge at the antistellar point on the far side. So they descended from this upland to a broader plain, broken by eroded hills and cut through by more river valleys following radii out from the substellar centre.

The nature of the vegetation changed too. The relatively lush but open forest of the substellar gave way to a more static landscape, much of it covered by tremendous leaves that blanketed the ground: a miserly gathering of all the light that poured down from a star that was still almost overhead. Beth realised that the more turbulent weather at the substellar itself must drive some change – storms would topple trees and clear the ground – and this passive light-guzzling strategy wouldn’t work there. And Beth remembered too that on her Per Ardua some ground-cover ‘plants’ like these had in fact been ‘kites’, flying beings, in a sedentary phase. But not here, not now; she saw no sign that these were anything other than vegetables, clinging to the ground as stationary and stately as stromatolites.