'I very much doubt that they did it deliberately, Pascale.'

'I realise that.' He had condescended to her, and she hated that, he knew. He also hated himself for doing it. 'I also know that stone-age aliens just don't have the means to influence the behaviour of their star, accidentally or otherwise.'

'We know they were more advanced than that,' Sylveste said. 'We know they had the wheel and gunpowder; a rudimentary science of optics and an interest in astronomy for agrarian purposes.

Humanity went from that level to spaceflight in no more than five centuries. It would be prejudiced to assume another species was not capable of the same, wouldn't it?'

'But where's the evidence?' Pascale stood to shake rivulets of settled dust from her greatcoat. 'Oh, I know what you're going to say -- none of the high-tech artefacts survived, because they were intrinsically less durable than earlier ones. But even if there was evidence -- how does that change things? Even the Conjoiners don't go around tinkering with stars, and they're a lot more advanced than the rest of humanity, us included.'

'I know. That's precisely what bothers me.'

'Then what does the writing say?'

Sylveste sighed and looked back at it again. He had hoped that the distraction would allow his subconscious to work at the piece, and that now the meaning of the inscription would snap into clarity, like the answer to one of the psychological problems they had been posed before the Shrouder mission. But the moment of revelation stubbornly refused to come; the graphicforms were still not yielding meaning. Or perhaps, he thought, it was his expectations that were at fault. He had been hoping for something momentous; something that would confirm his ideas, terrifying as they were.

But instead, the writing seemed only to commemorate something that had happened here -- something that might have been of great importance in Amarantin history, but which -- set against his expectations -- was bound to be parochial in the extreme. It would take a full computer analysis to be sure, and he had only been able to read the top metre or so of the text -- but already he could feel the crush of disappointment. Whatever this obelisk represented, it was no longer of interest to him.

'Something happened here,' Sylveste said. 'Maybe a battle, or the appearance of a god. That's all it is -- a marker stone. We'll know more when we unearth it and date the context layer. We can run a TE measurement on the artefact itself, too.'

'It's not what you were looking for, is it?'

'I thought it might be, for a while.' Then Sylveste looked down, towards the lowest exposed part of the obelisk. The text ended a few inches above the highest layer of cladding, and something else began, extending downwards out of sight. It was a diagram, of some sort -- he could see the topmost arcs of several concentric circles, and that was all. What was it?

Sylveste could not -- would not -- begin to guess. The storm was growing stronger. No stars at all were visible now, only a single occluding sheet of dust, roaring overhead like a great bat's wing. It would be a kind of hell when they left the pit.

'Give me something to dig with,' he said. And then started scraping away at the permafrost around the topmost layer of the sarcophagus, like a prisoner who had until dawn to tunnel from his cell. Only a few moments passed before Pascale and the student joined him in the work, while the storm howled above. 'I don't remember much,' the Captain said. 'Are we still around Bloater?'

'No,' Volyova said, trying not to make it seem as if she had already explained this to him a dozen times, each time she had warmed his mind. 'We left Kruger 6OA some years ago, once Hegazi negotiated us the shield ice we needed.'

'Oh. Then where are we?'

'Heading towards Yellowstone.'

'Why?' The Captain's basso voice rumbled out of speakers arranged some distance from his corpse. Complex algorithms scanned his brain patterns and translated the results into speech, fleshing out the responses when required. He had no real right to be conscious at all, really -- all neural activity should have ended when his core temperature had dropped below freezing. But his brain was webbed by tiny machines, and in a way it was the machines which were thinking now, even though they were doing so at less than half a kelvin above absolute zero.

'That's a good question,' she said. Something was bothering her now and it was more than just this conversation. 'The reason we're going to Yellowstone is...'

'Yes?'

'Sajaki thinks there's a man there who can help you.'

The Captain pondered this. On her bracelet she had a map of his brain: she could see colours squirming across it like armies merging on a battlefield. 'That man must be Calvin Sylveste,' the Captain said.

'Calvin Sylveste is dead.'

'The other one, then. Dan Sylveste. Is that the man Sajaki seeks?'

'I can't imagine it's anyone else.'

'He won't come willingly. He didn't last time.' There was a moment of silence; quantum temperature fluctuations pushing the Captain back below consciousness. 'Sajaki must be aware of that,' he said, returning.

'I'm sure Sajaki has considered all the possibilities,' Volyova said, in a manner which made it clear she was sure of anything but that. But she would be careful of speaking against the other Triumvir. Sajaki had always been the Captain's closest adjutant -- the two of them went back a long way; times long before Volyova had joined the crew. To the best of her knowledge, no one else -- including Sajaki -- ever spoke to the Captain, or even knew that there was a way to do so. But there was no point taking stupid risks -- even given the Captain's erratic memory.

'Something's troubling you, Ilia. You've always been able to confide in me. Is it Sylveste?'

'It's more local than that.'

'Something aboard the ship, then?'

It was not something to which she was ever going to become totally accustomed, Volyova knew, but in recent weeks visiting the Captain had begun to take on definite tones of normality. As if visiting a cryogenically cooled corpse infected with a retarded but potentially all-consuming plague was merely one of life's unpleasant but necessary elements; something that, now and again, everyone had to do. Now, though, she was taking their relationship a step further -- about to ignore the same risk which had stopped her expressing her misgivings about Sajaki.

'It's about the gunnery,' she said. 'You remember that, don't you? The room from which the cache-weapons can be controlled?'

'I think so, yes. What about it?'

'I've been training a recruit to become Gunnery Officer; to assume the gunnery seat and interface with the cache-weapons through neural implants.'

'Who was this recruit?'

'Someone called Boris Nagorny. No; you never met him -- he came aboard only recently, and I tended to keep him away from the others when I could help it. I would never have brought him down here, for obvious reasons.' Namely that the Captain's contagion might have reached Nagorny's implants if she had allowed the two of them to get too close. Volyova sighed. She was getting to the crux of her confession now. 'Nagorny was always slightly unstable, Captain. In many ways, a borderline psychopath was more useful to me than someone wholly sane -- at least, I thought so at the time. But I underestimated the degree of Nagorny's psychosis.'

'He got worse?'

'It started not long after I put the implants in and allowed him to tap into the gunnery. He began to complain of nightmares. Very bad ones.'

'How unfortunate for the poor fellow.'

Volyova understood. What the Captain had undergone -- what the Captain was still in the process of undergoing -- would make most people's nightmares seem very tame phantasms indeed. Whether or not he experienced pain was a debatable point, but what was pain anyway, compared to the knowledge that one was being eaten alive -- and transformed at the same time -- by something inexpressibly alien?

'I can't guess what those nightmares were really like,' Volyova said. 'All I know is that for Nagorny -- a man who already had enough horrors loose in his head for most of us -- they were too much.'

'So what did you do?'

'I changed everything -- the whole gunnery interface system, even the implants in his head. None of it worked. The nightmares continued.'

'You're certain they had something to do with the gunnery?'

'I wanted to deny it at first, but there was a clear correlation with the sessions when I had him in the seat.' She lit herself another cigarette, the orange tip the only remotely warm thing anywhere near the Captain. Finding a fresh packet of cigarettes had been one of the few joyful moments of recent weeks. 'So I changed the system again, and still it didn't work. If anything, he just got worse.'

She paused. 'That was when I told Sajaki of my problems.'

'And Sajaki's response was?'

'That I should discontinue the experiments, at least until we'd arrived around Yellowstone. Let Nagorny spend a few years in reefersleep, and see if that cured his psychosis. I was welcome to continue tinkering with the gunnery, but I wasn't to put Nagorny in the seat again.'

'Sounds like very reasonable advice to me. Which of course you disregarded.'

She nodded, paradoxically relieved that the Captain had guessed her crime, without her having to spell it out.

'I woke a year ahead of the others,' Volyova said. 'To give me time to oversee the system and keep an eye on how you were doing. That was what I did for a few months, too. Until I decided to wake Nagorny as well.'

'More experiments?'

'Yes. Until a day ago.' She sucked hard on the cigarette.

'This is like drawing teeth, Ilia. What happened yesterday?'

'Nagorny disappeared.' There; she'd said it now. 'He had a particularly bad episode and tried to attack me. I defended myself, but he escaped. He's elsewhere in the ship. I have no idea where.'

The Captain pondered this for long moments. She could tell what he must be thinking. It was a big ship and there were whole regions of it through which nothing could be tracked, where sensors had stopped working. It would be even harder trying to find someone who was actively hiding.

'You're going to have to find him,' the Captain said. 'You can't have him still at large when Sajaki and the others awaken.'

'And then what?'

'You'll probably have to kill him. Do it cleanly, and you can put his body back in the reefersleep unit and then arrange for the unit to fail.'

'Make it look like an accident, you mean?'

'Yes.' There was, as usual, absolutely no expression on the part of the Captain's face she could see through the casket window. He was no more capable of altering his expression than a statue. It was a good solution -- one that, in her preoccupation with the nature of the problem, she had failed to devise herself. Until then, she had feared any confrontation with Nagorny because it might put her in the position of having to kill him. Such an outcome had seemed unacceptable -- but as always, no outcome was unacceptable if you looked at it the right way.

'Thank you, Captain,' Volyova said. 'You've been very helpful. Now -- with your permission -- I'm going to cool you again.'

'You'll be back again, won't you? I do so enjoy our little conversations, Ilia.'

'I wouldn't miss them for the world,' she said, and then told her bracelet to drop his brain temperature by fifty millikelvin; all it would take to send him to dreamless, thoughtless oblivion. Or so she hoped.

Volyova finished her cigarette in silence and then looked away from the Captain, along the dark curve of the corridor. Somewhere out there -- somewhere else in the ship -- Nagorny was waiting, bearing her what she knew to be the deepest of grudges. He was ill himself now; sick in the head.

Like a dog that had to be put down.

'I think I know what it is,' Sylveste said, when the last obstructing block of stone had been removed from the obelisk's cladding, revealing the upper two metres of the object.

'Well?'

'It's a map of the Pavonis system.'

'Something tells me you'd already guessed that,' Pascale said, squinting through her goggles at the complex motif, which resembled two slightly offset groups of concentric circles. Stereoscopically merged, they fell into one group which seemed to hang some distance above the obsidian. And they were planetary orbits; no doubt of that. The sun Delta Pavonis lay at the centre, marked with the appropriate Amarantin glyph -- a very human-looking five-pointed star. Then came correctly sized orbits for all the major bodies in the system, with Resurgam marked with the Amarantin symbol for world. Any doubts that this was just a coincidental arrangement of circles was banished by the carefully marked moons of the major planets.

'I had my suspicions,' Sylveste said. He was fatigued, but the night's work -- and the risk -- had surely been worthwhile. It had taken them much longer to unearth the second metre of the obelisk than the first, and at times the storm had seemed like a squadron of banshees, only ever a moment away from inflicting shrieking death. But -- as had happened before, and would certainly happen again -- the storm had never quite reached the fury that Cuvier had predicted. Now the worst of it was done, and though streaks of dust were still rippling in the sky like dark banners, pink dawnlight was beginning to chase away the night. It seemed they had survived after all.

'But it doesn't change anything,' Pascale said. 'We always knew they had astronomy; this just shows that at some point they discovered the heliocentric universe.'

'It means more than that,' Sylveste said, carefully. 'Not all of these planets are visible to the naked eye, even allowing for Amarantin physiology.'

'So they used telescopes.'

'Not long ago you described them as stone-age aliens. Now you're ready to accept that they knew how to make telescopes?'

He thought she might have smiled, but it was hard to tell when she wore the breather mask.

Instead, she looked skywards. Something had crossed between the baulks; a bright deltoid moving under the dust.

'I think someone's here,' she said.

They climbed the ladder quickly, out of breath when they reached the top. Though the wind had lessened from its peak of several hours earlier, it was still an ordeal to move around topside. The dig was in disarray, with floods and gravitometers toppled and broken, equipment strewn around.

The aircraft was hovering above them, veering to and fro as it scouted landing sites. Sylveste recognised it immediately as one of Cuvier's; Mantell had nothing as large. Aircraft were in short supply on Resurgam: the only means of crossing distances more than a few hundred kilometres. All the aircraft in existence now had been manufactured during the early days of the colony by servitors working from local raw materials. But the constructional servitors had been destroyed or stolen during the mutiny, and consequently the artefacts they had left behind were of incalculable value to the colony. The aircraft regenerated themselves if they were involved in minor accidents, and never needed maintenance -- but they could still be ruined by sabotage or recklessness. Over the years the colony had steadily depleted its supply of flying machines.

The deltoid hurt his eyes. The underside of the plane's wing was sewn with thousands of heat elements which glowed white-hot, generating lift thermally. The contrast was too much for Calvin's algorithms.

'Who are they?' one of his students asked.

'I wish I knew,' Sylveste said. But the fact that this plane had originated in Cuvier entirely failed to cheer him. He watched it lower, casting actinic shadows across the ground before the heat elements slid down the spectrum and the plane settled onto skids. After a moment a ramp folded out and a cluster of figures trooped from the plane. His eyes snapped to infrared -- he could see the figures clearly now, even as they moved away from the plane towards him. Clad in dark clothes, they wore breather masks, helmets and what looked like strap-on armour, flashed with the Administration insignia: the closest the colony came to a fully-fledged militia. And they were carrying things -- long, evil-looking rifles held in double-grips, with a torch slung under each barrel.

'This doesn't look good,' Pascale said, accurately.

The squad halted a few metres from them. 'Doctor Sylveste?' called a voice, attenuated by the wind, which was still considerable. 'I've got some bad news, I'm afraid, sir.'

He had been expecting nothing else. 'What is it?'

'The other crawler, sir -- the one that left earlier tonight?'

'What about it?'

'They never made it back to Mantell, sir. We found them. There'd been a landslide -- dust had built up on the ridge. They didn't have a chance, sir.'

'Sluka?'

'They're all dead, sir.' The Administration man's heavy breather mask made him look like an elephantine god. 'I'm sorry. It's lucky not all of you tried to get back at the same time.'

'It's more than luck,' Sylveste said.

'Sir? There's one other thing.' The guard tightened his grip on his rifle, emphasising its presence rather than aiming it. 'You're under arrest, sir.'

K. C. Ng's rasp of a voice filled the cable-car's cockpit like a trapped wasp. 'You developing a taste for it yet? Our fair city, I mean.'

'What would you know?' Khouri said. 'I mean, when was the last time you set foot outside of that damned box, Case? It can't have been in living memory.'

He was not with her, of course -- there was nowhere near enough room for a palanquin aboard her cable-car. The car was necessarily small; nothing that would attract attention so close to the conclusion of a hunt. Parked on the roof, the vehicle had looked like a tailless helicopter which had partially furled its rotors. But rather than blades, the cable-car's arms were slender telescopic appendages, each terminating in a hook as viciously curved as a sloth's foreclaw.

Khouri had entered the car, and the door had slumped shut, barriering the rain and the low background noise of the city. She had stated her destination, which was the Monument to the Eighty, down in the deep Mulch. The car had paused momentarily, undoubtedly calculating the optimum route based on current traffic conditions and the generally shifting topology of the cableways which would carry it there. The process took a moment because the car's computer brain was not especially smart. Then Khouri had felt the car's centre of gravity shift slightly. Through the upper window of the gullwing door, she had seen one of the car's three arms extend to more than twice its previous length, until the clawed end was able to grasp one of the cables which overran the top of the building. Now one of the other arms found a similar grasping point on an adjacent cable, and with a sudden heave they were, in a manner, airborne. For a moment the car slid down the two cables to which it had attached itself, but after a few seconds the latter of the two cables had diverged too far for the car to reach. Smoothly, it released its grasp, but before it could fall the car's third arm swooped out and grabbed another handy cable which happened to cross their approximate path.

And then they slid for another second or so, and then fell again, and then rose again, and Khouri began to recognise a too-familiar feeling in her gut. What failed to assist matters was that the car's pendulous progress felt arbitrary, as if it was just making up its trajectory as it proceeded, luckily finding cables when it needed them. To compensate, Khouri ran through breathing exercises, restlessly tightening each finger of her black leather gloves in sequence.