âEasy,' said Meriel Redon, who appeared to be bound in a similar position next to Thalia: sitting on the ground with her back against the railings that encircled the polling core, her arms crossed and bound behind one of the uprights. âYou're okay now, Prefect Ng. You took a bad bump on the head, but there's no bleeding. We'll get you checked as soon as we're out of this.'
Through a curtain of pain, Thalia said, âI don't remember. What happened?'
âYou were down in the basement, getting ready to set the timer on your whiphound.'
âI was,' Thalia said foggily. She had a groggy recollection that there had been some kind of problem with the whiphound, but the details refused to sharpen.
âYou banged your head on one of the struts, knocking yourself out.'
âI banged my head?'
âYou were out cold. Citizen Parnasse carried you back up here on his own.'
The events began to come back to her. She remembered the second timing dial jamming, how she had come to the decision that she would have to detonate the whiphound manually. She remembered that awesome calm she had experienced, as if every trifling detail in her life had just been swept aside, leaving a breathtaking clarity of mind, as empty and full of possibility as the clear dawn sky. And then she remembered nothing at all, except waking up here.
âWhere is Parnasse?'
âHe went back down to set the timer,' Redon said. âHe said you'd shown him what to do.'
âNoâ' Thalia began.
âWe're expecting him back any minute. He said he'd be able to tie himself down when he arrived.'
âHe isn't coming back. There was a problem with the whiphound, with setting the five-minute fuse. I didn't bang my head. Parnasse must have knocked me out.'
Redon looked puzzled. âWhy would he have done that?'
âBecause I was going to set it off myself, while I was still down there. It was the only way. But he wouldn't let me. He's decided to do it himself.'
Comprehension came to Redon in horrified degrees. âYou mean he's going to die down there?'
âHe isn't coming back up. I showed him how to set the whiphound. He knows exactly what to do.'
âSomeone has to go down there, tell him not to do it,' Redon said. âHe can't kill himself to save us. He's just a citizen, just one of us.'
âWhen did he go?'
âQuite a long time ago.'
âHe can't set the fuse for longer than a hundred seconds. There's no reason why he needs to wait that long, if he's in place.'
âYou mean we could go any second?'
âIf the whiphound works. If the machines haven't already broken through and stopped him.' She knew she ought to feel gratitude, but instead she felt betrayed. âDamn him! He shouldn't have brought me back up here. It wasted too much time!'
âMaybe it wouldn't be a bad idea if one of usâ'
Redon never got to finish her sentence. Judging by the force of the blast, felt through Thalia's spine as it transmitted itself through the fabric of the polling core sphere, the whiphound must have detonated at nearly its maximum theoretical yield. It had been a new unit, she remembered belatedly: she'd checked it out of the armoury only a couple of weeks ago. There would still have been a lot of energy left inside it, anxiously seeking release.
The sphere rocked appreciably: Thalia saw the landscape tilt and then settle again at its former angle. The blast had been very brief: a spike of intense sound followed by a few seconds of echoing repercussions. Now all was silent again. The sphere was still. The landscape outside was still.
âIt didn't work,' she said. âWe're not moving. It didn't fucking work.'
âWait,' Caillebot said quietly.
âIt didn't work, Citizen. We're not going anywhere. The blast wasn't sufficient. I've failed you, used up our one chance.'
âWait,' he said.
âSomething's happening,' Cuthbertson said. âI can hear it. It sounds like metal straining. Can't you?'
âWe're tilting,' Redon said. âLook.'
Thalia craned her neck in time to see the white ball of the model polling core sphere roll across the floor, towards the window facing them.
From somewhere below there came a kind of twanging sound, as if the energy stored in a stretched spar had just been catastrophically released. The twanging sound was followed in quick succession by another, then a third, and then a volley of them too close together to count.
The tilt of the floor increased. Thalia felt her weight beginning to tug on the upright to which she was bound. The sphere must have been at ten or fifteen degrees to the horizontal already. She heard another series of metallic sounds: shearing and buckling noises, less like the failure of structural components than the cries of animals in distress.
The angle of the tilt reached twenty degrees and continued increasing.
âWe're going over,' she said. âIt's happening.'
Loose clothes and debris skittered across the floor, coming to rest along the curve of the outer wall. The architectural model slid noisily, then shattered itself to pieces. Thirty degrees, easy. Thalia felt an unpleasant tingling in her stomach. The landscape was tilting alarmingly. Through the windows, she could see aspects of the surrounding campus that had been obscured before. Suddenly it looked much further down than she had been imagining. Five hundred metres was a long way to fall. She remembered Caillebot's reaction when she'd outlined the plan:
That doesn't look survivable.
Maybe he'd been right all along.
Now the tilt was increasing faster. Forty degrees, then forty-five. Thalia's arms felt as if they were being wrenched out of their sockets, but it was only the effect of her bodyweight so far. When the sphere started rolling, it was going to get much worse. Fifty degrees. The lower extremity of the stalk was beginning to come into view through the windows. In one brief glimpse she knew she'd been right about the war machines. They covered it like a black mould, reaching as high up the shaft as it was possible to see. They must have been very close to the sphere itself.
Something gave way. Thalia felt the sphere drop several metres, as if the upper part of the stalk had crumbled or subsided under the changing load. And then suddenly they were rolling, pitching down the side of the stalk, the angle of tilt exceeding ninety degrees and then continuing to climb. The sphere shook and roared. There was no time to analyse the situation, or even judge how far down the stalk they had rolled. There was only room in Thalia's head for a single, simple thought:
It's working... so far.
She felt a momentary increase in the forces tugging at her body and judged that the sphere had reached the base of the stalk and changed its direction of roll from the vertical to the horizontal. She tried to time the duration of each roll, hoping to judge the distance they had travelled and detect some evidence that the sphere was slowing. But it was hopeless trying to concentrate on such matters.
âI think,' she heard Caillebot call out, between grunts of discomfort, âthat we've cleared the perimeter.'
âReally?' Thalia called back, raising her voice above the juggernaut rumble of their progress.
âWe're still rolling pretty fast. I hope we don't just bounce right over the window band.'
It was a possibility neither Thalia nor Parnasse had considered. They'd guessed that the sphere would have enough momentum to reach the edge of the band, but they had never thought about it moving so fast that it would skim right across, moving too quickly to stress the window enough to break. Now Thalia realised that they were open to the awful possibility that the sphere might traverse the entire window band and come to a rolling halt on the next stretch of solid ground.
âCan you see the band yet?' she asked.
âYes,' called out Meriel Redon. âI think I can. But something's wrong.'
âWe're coming in too fast?'
âNot that. Shouldn't we be rolling in a straight line?'
âYes,' Thalia said. âAren't we?'
âWe seem to be curving. I can see the window band, but we're approaching it obliquely.'
Thalia was confused and worried. They'd always assumed that the sphere would follow a straight course once it reached the base of the stalk, with only minor deviations caused by obstacles and friction. But now that she concentrated on the tumbling landscape and tried to make out the grey line that marked the edge of the window band, she knew that Redon was right. They were clearly off-course, at far too sharp an angle to be explained by the sphere crashing through the remains of the campus grounds.
âI don't understand,' she said. âWe went over this. It should be a straight roll all the way to the window band.'
âWe're still going to hit the window band,' Cuthbertson said, his voice reduced to a strangled approximation of itself. âYou've just forgotten about Coriolis force.'
âWe should be moving in a straight line,' Thalia said.
âWe are. But the habitat's rotating, and it's trying to get us to follow a helical trajectory instead. It's all about reference frames, Prefect.'
âCoriolis force,' Thalia said. âShit. After everything they taught me in Panoply, I forgot about Coriolis force. We're not on a planet. We're inside a fucking spinning tube.'
She'd become aware that the rate of roll was diminishing, the landscape cartwheeling around at half the speed from when they had begun the journey. She could begin to pick out details, landmarks that the Aubusson citizens had already noted.
âWe'll be okay,' Cuthbertson said. âWe're just going to hit a different part of the window band than we were expecting.'
âWill that make any difference?' she asked.
âDon't think so. We should break through as easily there as anywhere else.'
âAny second now,' Meriel Redon said. âWe're coming up on the band. Get ready, everyone. There's going to be a jolt when we hit the edge of the land strip.'
Thalia braced herself, in so far as bracing was possible when she was already bound like a sacrificial offering. She felt a moment of giddy vertigo as the sphere rolled over the edge of the landscape strip and crashed down onto the vast glassy plain of the window band. The ride became eerily smooth as they trundled over the geometrically perfect surface. With little friction save air resistance, the rate of roll was holding more or less steady.
âBreak,' Thalia whispered. âPlease break. And please let us be airtight when it happens.'
Dreyfus knocked on the door to the tactical room before stepping through. A certain deference was advisable. Dreyfus knew that his Pangolin clearance put him on a level footing with the seniors in some respects, but he saw no point in rubbing salt into that particular wound.
âDreyfus,' Baudry said, breaking off from whatever discussion she'd been having with the other seniors. âI'm afraid you're too late. You've just missed the demise of the Persistent Vegetative State.'
Without sitting down, Dreyfus moved to a position close to the Solid Orrery. The number of red lights hadn't changed since last time he'd seen it, but he could draw no consolation from that, knowing what it had cost just to slow Aurora's advance. âHow many'd we get out?'
âOne hundred and seventeen thousand, out of a total population of one hundred and thirty. Not bad, all things considered, especially as we were basically dealing with corpses.'
âWe've now concentrated our evacuation efforts on the targets we think Aurora will go for next,' Clearmountain said. âOur monitors show that the weevil flows are already changing direction, now they know the Spindle and the PVS are out of the picture.'
âYou mean nuked“,' Dreyfus said.
âWhatever. So far, though, we can't say where the flows are most likely to hit next. There are a number of possible candidates. Unfortunately, none of them are habitats where we've already started evacuating. We're starting from scratch.'
âWhere are the evacuees going?'
He could tell from their reactions that his question wasn't a popular one. âIn an ideal world, we'd ship them far across the Glitter Band, well beyond Aurora's expansion front,' Clearmountain said. âBut even with the high-burn liners, that would involve an unacceptable round-trip delay. Our only practical strategy has been to move the citizens to relatively close habitats, so that the turnaround time can be minimised.'
âGo on.'
Clearmountain cast a glance at the other seniors. âUnfortunately, Aurora's projected front is now beginning to impinge on some of the habs where we've been moving people.'
âI see.'
âWhich means that when we start evacuating those habs, we're also going to have to shift the recent refugees. With our current resources the situation is borderline containable, but as the front expands, and the number of endangered habitats grows geometrically, the refugee burden will soon become the predominant limiting factor.' Clearmountain offered his palms in a gesture of well-intentioned surrender. âSome tough calls may have to be made when that happens, Prefect Dreyfus.'
âToday we nuked two occupied habitats. We've already made tough calls.'
âWhat I mean,' Clearmountain said, with a strained smile, âis that we may have to focus our activities where they can do the most good.'
âIsn't that exactly what we're already doing?'
âNot to the degree that may shortly become necessary. In the interests of maximising the number of citizens we can evacuate away from Aurora's takeover front, we may have to prioritise assistance to those citizens least likely to hinder our efforts.'