‘Yeah. We’ll have a meal before we start off again. With all the senses we’ve got available, it’ll be perfectly safe riding at night.’

*

Despite her expectations, Kysandra managed to doze quite a lot as the unrelenting sun blasted the desert, taking the midday temperature close to fifty degrees Celsius. In the tent, it never rose above twenty-five.

She wasn’t hungry; she didn’t want to do anything. But Nigel insisted they eat towards the end of the afternoon. Her meal was some jibread, which was baked so long it was as tough and dense as a biscuit, but could be carried for weeks, and a meat paste chosen because it also could last for a long time without putrefying. She forced it all down and drank a lot more water from the chillflask. The high point was an apple, one from a sack they’d bought in Croixtown. It didn’t taste of much, and she thought the skin was starting to wrinkle up already.

They put their robes back on and went outside to break camp. The rest of the day continued in the same fashion as the morning’s journey. A steady measured progress. Up a dune, down the other side. Then again. Again. Tiny runnels of sand slipping away from the hooves. A track of churned-up sand in their wake. Twin grooves of the bladder carts’ wheels stretching out behind them, dwindling into the distance.

After an hour the sun sank behind the Bouge mountains, leaving the desert encased in a rosy twilight. The hard-packed sand turned a dull rouge colour. That shaded down to a murky grey before long. The clear sky darkened, allowing the frail nebula light to shine down. Air temperature began to drop towards the low forties Celsius.

Within her little cocoon of protective Commonwealth gear, Kysandra became more and more convinced that no one had ever come this far inside the Desert of Bone before. Explorers must have skirted the edges. Nothing more.

As the night wore on, the size of the dunes began to reduce, their height shrinking, slopes flattening out. She realized the breeze was fading away, too.

An hour after midnight, Nigel led the way over the last true dune. On the other side, the desert became tediously flat; washed by the insipid phosphorescence of the nebulas, it resembled a lacklustre becalmed sea. But it did allow them to pick up the pace as they started moving across the dreary terrain.

*

They stopped at three o’clock to water the horses. The animals were tired, but hadn’t protested at the night march.

‘At least nothing can creep up on us here,’ Russell said as they filled the water sacks. Even the dunes, barely ten miles behind, were lost to the dark horizon. The sensation of isolation was formidable.

‘There is no monster,’ Nigel assured him.

She wished she could believe so easily, but the Desert of Bone was a strange place.

Dawn arrived two hours later, a blazing crescent of gold light sliding up fast from behind the Salalsav mountains and pushing a pale blue haze ahead of it. By then Kysandra was feeling desperately weary. Even with a long rest yesterday afternoon, the night trek had left her drained.

‘Do we stop now?’ she asked. It was practically a plea.

‘When the temperature rises,’ Nigel replied impassively.

Kysandra’s horse kept walking as the day bloomed around them; the steady rhythm had become her whole universe. The heat increased inexorably, punishing the air. She could taste it in her mouth again.

Vivid sunlight revealed nothing, only how vast the Desert of Bone was. Today, even the surrounding mountains were lost to sight in the quivering miasma of roiling air that shrouded them.

‘Stop,’ Nigel ’pathed.

The order broke through Kysandra’s hypnotic stupor. Nigel had reined in his horse ten metres ahead. She hurriedly ordered her horse to halt behind him.

‘Anyone else see that?’ he asked.

Kysandra stared at the wobbling horizon, unsure where the land ended and the sky began. But there was a definite dark knot in the contorted air, and not even her reactivated Advancer-heritage eyes could focus on it. ‘What is that?’ she asked plaintively.

Nigel raised a module, pointing it at the dark smudge. ‘Mirage. There’s something over the horizon. Something big. Too far away for a reading.’ He lowered the module.

‘That’s lucky,’ she said. Navigation icons slipped across her exovision, linked to the small inertial guidance OCtattoo the Skylady’s medical module had printed on her shoulder. ‘Old technology,’ Nigel had said. ‘But we thought it might work here.’

He was right. The exovision data confirmed that the object, whatever it was, was situated east of the course they were taking to the epicentre of the desert.

Two months ago, the post had delivered the most expensive, elaborate atlas available on Bienvenido: a huge tome with fold-out charts which Nigel had ordered directly from the Captain’s Cartography Institute. The world’s main features had supposedly been copied from images originally captured during the approach of Captain Cornelius’s ship, with additional details supplied by various Geographical Association expeditions over the centuries. It certainly gave a reasonably accurate plan of the Desert of Bone, which they’d faithfully copied into their storage lacuna. There were no features within the desert, no hills no canyons; according to the atlas, its topography was blank.

‘I don’t think that’s entirely luck,’ Nigel said slowly. ‘It’s simply large enough to be refracted across a long distance. Which isn’t necessarily a good thing.’

‘Is it one of the other ships, do you think?’ she asked. ‘Did one crash here?’ The idea was frightening. What would it be like to stumble out of a wrecked ship and find yourself in this utterly inhospitable terrain? And everyone says there are a lot of bodies. A chill rippled over her skin, making her shiver inside the robe.

‘Possibly,’ Nigel said. ‘Though I’d expect a decent population centre to emerge close to anywhere a ship came down. And this end of the continent is one of the last areas to be developed. There are some fishing villages on the other side of the Salalsav mountains, but nothing major.’

‘Because they never got out of the desert.’

‘Cornelius wouldn’t have abandoned them.’

‘Then—?’

‘This is why we’re out here, remember? To find out. Come on, we’ll camp here for the day.’

This time, Kysandra fell asleep almost as soon as she stumbled into the tent. Nigel woke her late in the afternoon for a meal, which she ate enthusiastically.

It was still appallingly hot when they set off again in the unremitting glare of low sunlight. Nigel and Fergus said the mirage had been visible for most of the day. It skipped about in the distorted air, but the direction hadn’t varied by more than a few degrees.

That was the course they followed, with the mirage flickering directly ahead of them like some black sun poised on the horizon. Then it sank away in tandem with Bienvenido’s real sun, leaving the uniform desert stretching away to the infinity edge, where it blended into the sky. Kysandra’s exovision projected a single purple guidance line towards the vanishing point. She stared down it obsessively as the horse plodded obediently onwards into the night. The gentle phosphorescent light of the nebulas shone across them, as unchanging as the desert.

‘There’s something,’ Fergus announced.

It was long past midnight, and Kysandra’s determination and eagerness had abandoned her quite a while back when it became obvious that the mirage object wasn’t waiting just over the horizon. Now she was simply enduring the tedium of the trek, waiting for dawn and the tent to appear in her life.

She waited without real interest as Fergus dismounted and walked across the grainy sand to a small stone. Her retinas zoomed in. He bent down and picked something up. A scrap of cloth? But it disintegrated as soon as his fingers plucked it off the ground. Except for a small metal ring left sitting in his palm, which he stared at curiously. A direct channel opened to her u-shadow, and exovision threw up Fergus’s sight, complete with spectrographic analysis.