The Arrows of Time: Orthogonal Book Three (48 page)

The jetpack overshot the rim of the base, and the rock below her fell away to be replaced by black emptiness then a sudden, shocking dawn. She could see the blazing lights of the half of the
transition circle that the mountain had been blocking, just peeking above the distant horizon. Agata sketched a down-arrow and the jetpack brought her closer to the rock; the dawn ahead vanished,
but she still had the other half of the circle behind her. The base was slightly convex, so, however low she dropped, the
Peerless
wouldn’t hide the entire transition circle,
plunging her into complete darkness.

She looked around for the others; she could just make out Serena away to her left and another anti-saboteur to her right. The jetpacks had been programmed to take the volunteers to equally
spaced points above the rim, but from here it was up to each of them to choose their path on a sweep in towards the axis.

The rock below her was a blur, moving past at more than a saunter every pause, but if she tried to match its velocity she’d be constantly using her jets to provide the necessary
centripetal force – which would empty her air tank long before she got halfway to the axis. In all her training exercises with Tarquinia, in all the manoeuvres she’d performed around
the
Surveyor
, she’d never faced anything like this.

The occulters could be waiting almost anywhere; in their final flight they could cover a lot of distance quickly. She couldn’t assume that they’d all crawled close to their targets.
So she had to find a compromise: she had to slow the relative motion of the rock just enough so she’d be sure to notice one of the machines sweeping by, and then try to move closer to the
axis as quickly as she could, lessening the drain on the jets.

Agata turned herself around so she was facing the surface at an angle where she caught the reflection of the stars. The grey blur shimmered with colour now, the texture visible if still
mysterious. She sketched a double arrow to begin reducing her relative motion; the jetpack complied, though it sent a warning message through her corset, alerting her to the cost.

She waited anxiously, afraid that this unrehearsed strategy would get her nowhere, but then the transition came in an instant: suddenly, the shimmer from the rock was comprehensible. Agata could
see the small bumps and concavities, the fine crevices, an endless parade of details rushing by beneath her. The occulters had been clad well enough to blend in with the stone around them from a
distance, but she was only a couple of strides from the surface. If she kept her concentration, the machines ought to be unmissable.

The mountain completed each rotation in less than seven lapses; her motion was stretching that out threefold, but rather than hanging back to witness a full turn at every radius she had to trust
her companions to cover their own portions of the territory. Agata wished she could have made it a mathematical certainty that no square scant would go unsearched, but before she’d been out
here and seen the conditions she’d been in no position to make binding plans. All she could do now was hope that most of the team found their own workable strategies, and between the symmetry
of their initial placement and the shared conditions that prompted their individual actions they’d end up executing a combined sweep without too many gaps.

She began moving steadily in towards the axis.

The change below her was so stark and it came so abruptly that Agata almost began chasing it, but she caught herself in time. The smooth black expanse of the engine’s rebounders was
unmistakable, and the visual jolt of entering it was followed by near-perfect homogeneity. The idea of the occulters drilling into this precious lode was shocking – and it would also be the
place where their camouflage was the least effective – but Agata decided not to speed past the region. However strong the argument for the machines avoiding it, she couldn’t trust her
adversaries not to exploit that presumption.

The surface became rough and grey again. Agata forced herself to readjust her expectations: her prey would show much less contrast now. The temptation to look around for her companions was
growing, as much out of a longing for the support of their presence as any real fear for their safety. But with her front eyes fixed on the rock below, her rear gaze couldn’t reach beyond the
blackness of the orthogonal cluster. She tried to assuage the pangs by rekindling her anger with Ramiro and Tarquinia; at least that made her feel stronger and more focused. But as the pits and
cracks in the stone swept by, she thought of Azelio, who believed that all their efforts were in vain. If a meteor had always been on its way, this charade would not deflect it.

A shape with hints of regular borders passed below her and was gone. Agata raised a triangle on her chest, the preprogrammed symbol to send the jetpack in pursuit. She waited anxiously for the
rock to slow, but when it halted there was nothing below her. She edged sideways, stride by stride, and then there it was fixed to the rock: an occulter with a small package dangling from it, held
in place by nothing but hooks and strings.

Ramiro had given her no details, but she’d been expecting some far more robust form of attachment. She took the knife from her tool belt, grabbed hold of the package and cut the
strings.

The bombs would be driven by timers alone; any kind of trigger based on location would be too unreliable to take out all twelve channels simultaneously, and navigation was the occulters’
job. Still, Agata kept the centrifugal weight on her cargo constant as she ascended from the rock, following a helix that kept the surface motionless beneath her. If everything she’d surmised
was mistaken and some accelerometer was ready to cry foul, better not to take a piece of the mountain with her.

When she’d reached a decent altitude she let the jetpack kill her circular motion and spare itself the costly countervailing force. Nothing exploded. Agata was tempted, briefly, to try to
prise open the stone box and take a look at the mechanism inside, but the risk of a booby trap seemed to outweigh any prospect of learning something useful.

She was still ascending slowly, in free fall now. She released her hold on the bomb, then instructed the jetpack to return her to the point where she’d left off. As she watched the package
shrink into the darkness, a glorious ache of hope came to her unbidden. There were only a dozen bombs: the volunteers outnumbered them more than two-to-one. If even half the other searchers were as
lucky as she’d been, the job would soon be done.

Back above the rock face, Agata fought to maintain her concentration. Twice she chased features in the stone that turned out to be nothing – perceptual illusions, or wishful thinking. It
was better to pursue false alarms that to miss a single bomb, but her air supply wasn’t infinite.

Looking back towards the rim she caught a glimpse of another searcher, a lonely silhouette against the blaze of the transition circle. By now there was no way of guessing who it was, but the
figure looked safe and busy. It was tempting to exchange a few words, to compare counts, to share strategies . . . but even in its tightest directional mode the link was only for emergencies, so
Agata did nothing to stop their drift apart.

The next find was so clear that Agata cursed her stupidity as she formed the triangle; the phantoms on which she’d wasted so much air seemed inexcusable now. As the rock halted, the
occulter appeared almost directly below her, but she was surprised to see how different the package looked from the last one.

She moved closer. There were no strings; the bomb was secured to two posts that rose from the occulter’s arms, lifting the rigid assembly clear of the dodecahedral core that held the air
jets. But how had these posts been attached, out on the slopes? Was this the occulter that Tarquinia had repaired – and she’d had to perform some strange modifications in the void?

Agata was baffled, but she didn’t have time to make sense of it. She took a wrench from her tool belt and set to work; the jetpack braced her with yet more expenditure of air. She tried to
turn the post itself, but it was too smooth and she could get no purchase on it. She groped around the attachment point on the arms, but there was no bolt head. The posts seemed to be glued in
place.

She closed one hand around the occulter’s arm then shut off her jetpack’s airflow completely, letting herself hang down across the vertical rock face. She took a flat bar and
inserted it between the machine’s arm and the rock, then began trying to prise the splayed drill bits out of the holes they’d made. But however hard she strained there was no
perceivable effect; the drills were mounted too securely and the rock itself wasn’t going to crack.

If she’d had more air she could have tried taking the drill assembly apart; she’d put half of them together herself, so she should have been able to reach in and unscrew all the same
bolts by touch alone. But not while she was clinging to this sheer drop. She took a high-powered coherer in her free hand and began carving through the posts that held the bomb in place.

Every few lapses she had to stop and wait for the occulter to cool down; it wasn’t smart enough to use its own air to deal with this unexpected contingency, and the heat was slow to
dissipate into the rock. At least her own need to be able to hold onto the frame gave her a clear signal to act; it was unlikely that any temperature she could tolerate on her skin would be high
enough to trigger the explosive. When the second post was all but severed, she started up her jetpack to support her and then snapped the post by hand.

Agata moved quickly into a disposal trajectory, cancelling her motion around the axis as she ascended – rising a little faster than before, now that her cargo would have less time to reach
a safe distance. She released the bomb and resumed the search. She was exhausted, but she still had enough air to go farther.

More experienced now, she dared to let the rock below her blur a little, trading off perfect clarity for less costly centripetal force. Agata didn’t want to grow complacent, but the
numbers were already better than she’d dared hope. While the majority of the team had barely been into the void before, five people had done maintenance work out on the hull. If those five
alone had dealt with two bombs each, as she had, the job would already be completed.

The amorphous blur below her was broken by a sharp edge spinning by. Agata went in pursuit, astonished by her luck. She was beginning to pity all the searchers who must have come just as far
with no result; everyone would understand that that might happen to them, but three times now she’d seen the signs that their collective effort was heading for victory, while others would
still be wondering if the whole endeavour had been misconceived.

The third occulter came into view. The cargo was attached in exactly the same manner as it had been on the last one. Agata didn’t delay her assault; she grabbed one of the posts, shut off
the jetpack and began applying her coherer. But as she worked, she sifted through the possibilities.

Tarquinia had not repaired the lost occulter with stone and glue. This one and the last had not picked up their cargo in any manoeuvre out on the slopes; the bombs had been glued into place in a
workshop somewhere. But how and why would Giacomo’s people have retrieved occulters from the slopes in order to do that? The answer was that they hadn’t. They’d built occulters
for themselves, and affixed the bombs before sending them out.

Agata moved her grip and began cutting through the second post. Three bombs diverted out of a dozen had seemed glorious. Three out of an unknown swarm could mean anything.

Before she severed the second post completely, she stopped to think through her choices. If she spent air carrying the bomb onto the same kind of path as the others, that would be the end of her
contribution; she’d have too little air left to intervene in any other way. But if there were already enough bombs waiting above the light collectors to cause the disruption, there was no
need for this one to be carefully positioned. She could simply let it fall away into the void.

Agata looked up across the rock face; she could see a glimmer from the transition circle reflected in the dome of one of the light collectors. How many other bombs had been grabbed and slowed
and sent to play their part in the pyrotechnics? She should trust her fellow searchers to have caught at least half a dozen by now – all the more so, given how plentiful they’d turned
out to be.

She had one hand around the arm of the occulter, which remained firmly attached to the mountain. She snapped the second post and tossed the freed bomb over her shoulder, watching with her rear
gaze as it tumbled down and disappeared.

But how many remained, clinging to the rock, waiting to make a final dash towards the collectors? A dozen? A gross? Agata closed her eyes and thought of letting go, falling clear of everything
and losing herself in the stars.

She’d wanted a glimpse of the reunion before she died, but in the end the only thing that the future had ever promised her was the cosmos meeting up with itself: every particle, every
field, every wrinkle in space matching perfectly as they came full circle. The geometry that achieved that had no need to please her; it was what it was, and she’d never been more than a tiny
part of it. The miracle was that she’d lived to understand its nature as well as she had. But if a meteor struck or the bombs blew the axis open, she did not want to stay and witness the
carnage.

Agata opened her eyes. Her right arm was aching; she pulled herself up and managed to grab the occulter with her left hand as well, but it was too awkward maintaining both holds so she let her
right arm rest completely. She checked the clock on her belt by touch; less than two chimes remained to the disruption. She wasn’t going to flee. She had no hope of finding another occulter
on the rock face, but the time was approaching when the bombs could come to her.

She stared down into the transition circle, but then she caught herself and turned her gaze to the side, trying to adjust for her own rotation and the arc that her adversary would need to follow
as it fought to cancel its greater sideways velocity and spiral in on the target.