Anathem

The darkness was nearly perfect. Arbre was on the other side of the ship, and shed no light here. A new moon, though, was swinging up through the cluttered horizon of the nearest shock piston, strewing faint light by which we cut ourselves apart and sorted ourselves out. Our magnetic boot-soles stuck faintly to the icosahedron, a rubble of nickel and iron. Moving like a man with gum on the soles of his shoes, Sammann made the rounds and checked our connections to the rope/wire.

“This facet will remain in darkness for another twenty minutes,” Jesry informed us, “after which we have to move to that one.” I supposed he was pointing at one of the three shock pistons that made up our local horizon, but I couldn’t see him. As the Daban Urnud revolved around Arbre, the terminator-the dividing line between the sunlit and shaded halves of the icosahedron-crept around it. On any given facet, sunrise or sunset would be explosively sudden. We’d better not get caught in the open when it happened, because the citadel-like complexes that loomed over the twelve vertices had clear views over the surrounding facets.

“According to my equipment,” announced Fraa Gratho, “we did not get illuminated by any short-range radar.”

“They simply don’t have it turned on,” said Lio. “But sooner or later, they’ll probably notice the monyafeeks that Fraa Jad cut loose, or the Cold Black Mirror, and then they’ll go to a higher state of alert. So, which way to the World Burner?”

“Follow me,” said Fraa Osa, and started walking. If walking was the right word for such a clumsy style of locomotion. I’d like to say we moved as drunks, but it would be an insult to every sloshed fraa who had staggered back to his cell in the dark. Much of our twenty minutes of darkness was burned moving the first couple of hundred feet. After that, though, we learned, if not what to do, then at least what not to do, and reached the nearest horizon with a few minutes’ darkness to spare.

The shock piston was like a pipeline half-buried in the rubble, but reinforced with fin-like trusses to prevent it from buckling like a straw when it was under load. At its ends, about a mile away in either direction, it swelled like the end of a bone and developed into a heavy steel knuckle. Five such knuckles, coming together from different directions, formed the base of each vertex. Each vertex was different, but in general they had been cobbled together from a mess of domes, cylinders, gridwork, and antennae. Extravagant bouquets of silver parabolic horns flourished from their “tops,” waiting for their turn to gaze into our sun and steal some of our light.

The triangular rubble-field across which we’d been walking didn’t butt up hard against the shock piston, because there had to be some give in the system; a shock absorber that had been in effect welded to a stiff triangular plate all along its length would not be able to function. Instead the facet stopped ten feet short of the truss-work that enshrouded the shock, and was sewn to it by a system of cables that zigzagged over pulleys. At a glance, it looked awfully complicated, and made me think of sailboats, not starships. But since the Urnudans had been building such things for a thousand years I guessed they had come up with a way to make it work.

Light shone up from the chasm below. As we neared it we slowed, bent forward, and gazed into the interior of the icosahedron, a volume of some twenty-three cubic miles, softly illuminated by sunlight slitting in through other such gaps and scattering from the icosahedron’s inner walls and the sixteen orbs. It was all as we’d seen it rendered on the model, but of course to see it in person was altogether different. The view was dominated by the nearest of the orbs, swinging by as fast as the second hand on a clock, helpfully painted with a huge numeral in the Urnudan writing system. I’d learned enough of this to translate it as number 5. Orb 5 housed high-ranking Troans.

All of my instincts told me to fear the jump across the gap, because if I “fell in” I would drop for some vast distance before getting splattered on a rotating orb. But of course there was no gravity here, no down, nothing to fall into.

Osa went first, launching himself across the gap and getting himself established on the struts that lent strength to the shock piston. Vay was last on the line. Once we’d all made it over, we hand-over-handed our way across the shock out of concern that the snapping of our magnetic boots against its steel would create an obvious acoustical signature. There was a dizzy moment when our settled conception of up and down was challenged by the next facet swinging into view, defining a new level and a new horizon. Then we got used to it and floated across another gap using the same procedure as before. This was perhaps an overly cautious way to travel ten feet through space. But if we all did it at once, and jumped too hard, we might drift away.

Sun was striking the struts we had just passed over as we planted our feet on the next facet of the icosahedron, where we could be assured of a few hours’ darkness. This was more time than we needed. Or, to speak truthfully, it was more than we had, since we only had an hour’s oxygen remaining, and the tender was gone.

Two miles away-directly across the facet-was a hydrogen bomb the size of a six-story office building. It was essentially egg-shaped. But like a beetle caught in spider’s webbing, its form was blurred by a fantastic tangle of strut-work and plumbing connecting it to the vertex-citadel. Indeed, that whole vertex appeared to have no practical use other than to serve as a support base for the World Burner. Even if it hadn’t been so enormous, it would have been a difficult thing to miss, because it was all lit up.

Lit up for the benefit of a hundred people in space suits clambering around on it.

“Do you think they’re getting ready to launch it?” Arsibalt asked.

“I don’t think they’re giving it a new paint job,” Jesry said.

“Very well,” Lio said. I didn’t know who he was speaking to, or what he was giving his assent to. A click on the line suggested that someone had just jacked out.

Our view of the World Burner complex was interrupted, now, by four black-space-suited figures who had broken away from the rest of us. In the dark, with the suits in stealth mode, we could not tell one another apart, but something in the way that these four moved convinced me that they were the Ringing Vale contingent. They walked abreast, with one-presumably Fraa Osa-slightly ahead of the others. They were spreading a little farther apart with each step.

“Lio? What is happening?” I asked.

“An Emergence,” he reasoned.

When the four Valers were spaced about twenty feet apart, Fraa Osa deployed his skelehands and, like a steppe rider in a shootout, drew a pair of pistol-like objects-the cold gas thrusters-from holsters bracketed to the hips of his suit. The other three did likewise. Then, to all appearances, Fraa Osa fell on his face. He planted his feet next to each other and let his momentum carry his body forward, peeling his magnetic soles loose from the rubble. As soon as he lost that connection to the icosahedron, his feet swung up and his whole body pivoted in space until he was prone. And in the same moment he began to glide headfirst toward the World Burner. He was holding both arms down to his sides, pointing the cold gas guns toward his feet, using them to thrust himself across the rubble plane, like a low-flying superhero. Vay, Esma, and Gratho were all doing likewise. In their wake we could see a roiling in the light, like heat waves, as the plumes of clear gas dissolved into space. At first their movement was achingly gradual, but they rapidly picked up speed, sometimes porpoising up, then correcting it with a calm inflection of the wrist, spreading out as they vectored themselves toward different parts of the World Burner complex, sliding with a kind of wicked, silent beauty over the glossy purple-blue rubble plane. We were able to see them only in silhouette against the lights of the sprawling complex-and that only for the first few moments of their flight. Then they were as invisible to us as they were to the space-suited Geometers swarming over the bomb.

Lio announced, “We have perhaps only a few minutes to get inside and find something to breathe before every door in the Daban Urnud is locked against us.”

“What about the Valers?” Arsibalt said.

“I think it would be wisest to assume that they and everyone working on the World Burner are as good as dead,” Lio said, after a moment’s thought.

“They are attacking now?” I asked.

“They are boarding it now,” Lio said.

Or-technically speaking-reminded me. For we had discussed this eventuality. “What if, when we come in sight of the World Burner, we see evidence that the Geometers are just about to launch it?”

“Ah, well, of course that would change everything, we’d have to fork to a completely different branch of the plan, not a moment to spare!” I knew we’d gone over it. But I had filed it, in my head, under the category of “things very unlikely to happen, hence safely forgotten.” Lio, however, had not forgotten. “If the Valers can manage to get aboard the World Burner covertly, they’ll hide, and take no further action until just before their air supply runs out. That’s to give the rest of us time to find a way in. But if the World Burner launches-or if someone sees them, and raises the alarm-well-”

“Bad things will happen,” Jesry snapped.

“So we might or might not have a little time,” I said.

“Which means, we should act as if we have none at all,” Lio returned. “Jules?” For the Laterran had been silent for a long time. “You still with us?”

“Pardon me,” Jules returned. “I am amazed, thinking of the havoc that our friends of the Ringing Vale are about to unleash. It is an inconceivable nightmare for the Pedestal, the worst embarrassment they will have suffered in one thousand years. My loyalties are torn several ways, you know.”

“No matter how much conflict is in your soul,” I said, “you can’t possibly object to the destruction of the World Burner, can you?”

“No,” said Jules softly, but distinctly. “In that my feelings are unalloyed. What a shame, if some of those working on it are slain! But to work on such a horrible device-” He did not finish the sentence, but I knew that, inside his space suit, he was shrugging.

“So mainly you just don’t want to introduce Everything Killers to the Daban Urnud,” I said.

“That is certainly correct.”

Lio broke in: “I never thought I’d hear myself saying this, but: take us to your leader,”

“I beg your pardon?”

“Point us to the Urnudans. Then your work is done. You can go home and get a decent meal.”

“Which is more than we can say for ourselves,” Arsibalt pointed out. “Yes,” Jules said, “the irony. No food for you. Not here!”

“So then,” Lio said, “what is your decision?” All of us shared his impatience, if for no other reason than that we were running out of air. I’d like to report that I was still thinking coolly, applying the Rake to everything that was clattering through my mind. But in truth I was stunned and bewildered and-if this made sense-hurt by the sudden departure of Osa, Vay, Esma, and Gratho. I’d known, of course, that there were various contingency plans. Had never fooled myself that I could know all of them. But I’d been telling myself all along that the Valers would always be with us. When I’d first seen them on the coach at Tredegarh I’d been horrified by the idea that I was about to be sent off on the kind of mission where such persons might be needed. But over the days since, I had grown used to-and proud of-being on just such a mission. Now, here we were, at its most critical moment, and the Valers were suddenly gone, without explanation, without even a “goodbye and good luck!” The logic of the decision they’d made was unassailable-what could be more important than disabling the World Burner? But where did it leave the rest of us?

“Is it possible,” I heard myself saying, “that we are a spent delivery mechanism? Like those boosters that threw us into space-to be dumped into the sea?”

“That’s totally plausible,” Jesry said without hesitation. “We did our lessons well and played some clever tricks to get the four Valers here. That job is done. Now, here we are. No food, no oxygen, no communications, and no way home.”

“You overestimate the importance of the World Burner,” Jad announced. “It is a bluff. Its existence forces our military to act in ways it would not otherwise. Its destruction would give Arbre back a measure of freedom. But what use the Sæcular Power would make of that freedom is yet to be known, and our actions may yet be of some importance. We go on.”

“Jules?” Lio said. “How about it?”

“It is tempting to drop through this opening before us, no?” Jules said. For we had instinctively turned our backs on the World Burner, as if this would protect us from whatever was about to erupt there. Once more we were gazing down into the gap, watching Orbs 6 and 7 rotate past, glimpsing the Core in the cleft between them. “But then we are in the light, where we may be seen. And the Orbstack rotates with too much velocity for us ever to catch it. No. We must go in via the Core. But to enter the Core, we must first go in at a vertex.” He toddled around until he was gazing at the vertex that, as we faced the shock piston, was to our left. “That is the observatory. You’ve studied the pictures.” He toddled right. “That one is a military command post.”

“Does the observatory have airlocks?” Arsibalt asked. For all of us were now looking leftward-no one felt up to invading a military command post, not after we’d lost our Valers.

“Oh yes, you are looking at one,” said Jules, and began walking toward it. We fell in step.

“Er-I am?”

“The dome that houses the telescope is, itself, a great airlock,” Jules explained.

“Makes sense,” Jesry said. “To work on the telescope, they’d want to flood the dome with air. Then, when they were ready to make observations, they’d evacuate it and expose it to space.” Which is where I normally would have become irritated with Jesry for lecturing the rest of us. But it went by me. I was fascinated, dumbfounded, by an idea I had not dared to think of for a week: taking my suit off. Being able to touch my face.

Arsibalt was on the same track: “The way I smell will probably seem funny when I reminisce about it years hence.”

“Yes,” Lio said, “if odors can travel between cosmi, everything down-Wick of us is about to die.”

“Thanks for the preview,” Jesry said.

“Let’s not get ahead of ourselves,” I suggested.

Sammann asked, “Is anyone going to be on duty in this observatory?”

“Perhaps not physically there,” Jules said. “The telescopes are controlled remotely on our version of the Reticulum. But the big one will be in use, certainly-making a survey of your lovely cosmos, which is all new to us.”

The vertex was looming mountainously as we carried on this conversation. Old instincts warned me that we had an exhausting climb ahead of us. But, of course, it was no climb at all, because we were weightless. Without having to discuss it we made for the “highest” and largest of the domes, which, as Jules had promised, was open. It was a spherical shell, split into two hemispheres, which had spread apart on tracks to expose a multi-segmented mirror with a diameter of some thirty feet. We all clambered through the gap between the hemispheres, which was wide enough to throw a three-bedroom house through, and hand-over-handed ourselves “down” to the level of the trusses and gimbals that supported the mirror-all following, I think, a sort of instinct to get indoors, under cover, away from the terrible exposure we had been living with for so long. Jules pointed out a hatch by which we could gain entry to the pressurized regions of the vertex once the dome had been closed and filled with air. There was even a nice big red panic button that we could slam to emergency-pressurize the dome. But he advised us not to use it, because this would trigger alarms all over the Daban Urnud. Instead he pulled himself up on the struts that held the telescope’s objective suspended at the mirror’s focal point. He peeled the reflective blanket off his chest and stuffed it in there, then clambered “down” to rejoin us. Meanwhile, the rest of us tried to stay calm and control our breathing. Arsibalt, who used more oxygen than anyone else, was down to ten minutes. Sammann had twenty-five; the two of them swapped oxygen tanks. I had eighteen. Lio suggested we all try to eat as much as possible; if we were separated from our suits, we’d have no food left except for a few energy bars that we could carry with us. So I sucked more gruel from the nozzle and made a prolonged and labored effort not to throw it right back up into the scupper.

“Hello!” called Jules, more as an exclamation than a greeting. It took us a moment to understand that he was responding to a face that had appeared in the porthole of the hatch: some cosmographer come to see why the big scope had gone dark. Based on Jules’s lessons, I guessed, from the hue of her eyes and the shape of her nostrils, that she was Fthosian. And, though it would take some time to learn Fthosian facial expressions, I reckoned I had now seen two of them: befuddlement followed by shock as a matte black space suit of unfamiliar design loomed in her window. Jules grabbed handles flanking the hatch and pressed his face plate against the glass. Then we all had to turn down the volume in our phones as he began to holler in what I assumed was Fthosian. The woman inside got the idea and pressed her ear against the window. Sound would not travel through the vacuum of space, but, by shouting loud enough, Jules could excite vibrations in his face-mask that would be transmitted by direct contact into the glass of the porthole and thence into the cosmographer’s ear.

He repeated himself. He somehow managed to sound more cheerful than desperate. His tone seemed to say it was all in good sport. The woman’s lips moved as she shouted back.

The dome illuminated. I reckoned she’d hit the light switch, to get a better look at what was going on. But on second thought this light was pouring in through the gap between the hemispheres. The sun must have risen? We’d been warned of explosive sunrises. But this seemed explosive in more ways than one; the light flared, faded, and flared brighter. It burbled and boiled. A silent concussion passed through the frame of the icosahedron. Lio sprang up so smartly that he almost committed the fatal mistake of flying straight up out of the dome and off into space. But he caught himself short by gripping the comm wire that linked him to the rest of us, and swung around above the telescope mirror until he finally contrived to stop himself short on the edge of a dome-half. The light, which was slowly dying, reflected in his face mask. “The World Burner,” he said, “I think they must have blown the propellant tanks.” Then, with a sudden exclamation, he pushed off and glided back “down” to what I was thinking of as the floor of the dome. For the giant hemispheres had gone into movement, and the slit between them was narrowing decisively. The lights really did come on now.

The slit disappeared with a clunk, felt not heard. For better or worse, we were trapped here now. I kept eyeing the big red emergency button. I had eight minutes.

A readout on my display began to change: outside air pressure, which had been a red zero ever since I’d been launched into the vacuum of space, was climbing up toward the yellow zone. Jules had noticed the same thing; he went over to a grated vent near the hatch and reached for it. His arm was batted aside by inrushing air.

“Thank Cartas,” Arsibalt said, “I don’t care what cosmos this air came from. I just want to breathe it.”

“While we are waiting, re-acquaint yourselves with the doffing procedure,” Lio told us. “And show yourselves.” He pulled up the screen that had been hiding his readouts. The rest of us did likewise. For the first time in a couple of hours we were able to see one another’s faces on the speely screens and to check one another’s readouts. I could not see everyone in the group, because we were distributed around a cluttered and complex space “beneath” the mirror supports. But I could see Jesry, who had two minutes. I had five. I swapped canisters with him; it was taking a long time to pressurize the dome.

A few minutes later the external pressure readout finally changed from yellow to green: good enough to breathe. Just as my oxygen supply indicator was going from red (extreme danger) to black (you are dead). With my last lungful of Arbre air I spoke the command that opened my suit to the surrounding atmosphere. My ears popped. My nose stung, and registered a funny smell: that of something, anything, other than my own body. Lio, who’d been keeping a sharp eye on my readouts (I had less oxygen than anyone else that I could see), stepped behind me and hauled the back of my suit open. I withdrew my arms, got a grip on the rim of the HTU, and pulled myself, stark naked, out of the accursed thing. I breathed alien air. My comrades watched me with no small interest. The only other Arbran to have breathed this stuff had been the Warden of Heaven, who apparently hadn’t lasted more than a few minutes. My hands flew to my face. I kneaded it, scratched my nose, rubbed a week’s sleep from my eyes, ran my fingers up into my hair. Could have thought of more edifying things to do, but it was a biological imperative.

Lio groped on his front, found a switch, flicked it. “Can you hear me?”

“Yeah, I can hear you.” The others took to groping for their switches.

“Not that it makes a difference-since we all have to get out-but what is it like, my fraa?”

“My heart is pounding like crazy,” I said, and paused, since to say that much had worn me out. “I thought I was just excited, but-maybe this air doesn’t work for us.” I was speaking in bursts between gasps for air; my body was telling me to breathe faster. “I can see why the Warden of Heaven blew an aneurysm.”

“Raz?”

Breathe, breathe. “Yeah?” Breathe breathe breathe…

“Get me out of this thing!” Lio insisted.

Jesry grabbed Lio, spun him around, yanked his door open. Lio got out of his suit as if it were on fire. He floated over with a mad look on his face. All my habits from home told me to get out of Lio’s way when he approached in that mood, but I simply didn’t have the strength. His arms, which had subjected me to so much rough treatment over the years, came around me in a bear hug. He pressed his ear against my chest. His scalp was like thistles. I felt his rib cage begin heaving. Jesry and Arsibalt and Jules were swimming free of their suits. Jules went straight to the hatch, threw a lever, and shoved it open. Everything faded-not to darkness but to a washed-out yellow-gray, as if too much light were shining through it.

Fraa Jad and I were floating in a white corridor. I was naked. He was dressed in one of the grey coveralls we’d brought up in our kit. Evidence suggested he had been rummaging in a steel locker set into the wall. Two clumps of silvery fabric were floating near him. He teased one open. It turned out to have arms and legs. From time to time he glanced my way. When he noticed me looking at him, he tossed me a grey packet in a poly bag: another folded-up coverall. “Put this on,” he said. “Then, over it, the silver garment.”

“Are we going to put out a fire?”

“In a manner of speaking.”

The effort of tearing open the poly wrapper set my heart pounding. Pulling on the coverall plunged me deep into oxygen debt. Once I had recovered enough to get a few words out, I asked, “Where are the others?”

“There is a Narrative, not terribly dissimilar to the one you and I are perceiving, in which they went to explore the ship. Their plan is to surrender peacefully whenever someone notices them.”

“Is there any particular reason they left us behind?”

“Emergence from the suit after so long. Finding oneself in a confined space after having grown accustomed to the unobstructed vastness. Breathing an atmosphere from a different cosmos. Effects of long-term weightlessness. General stress and excitement. All of these induce a syndrome that lasts for a few minutes, a kind of going into shock, that can produce confusion or even loss of consciousness. Soon it passes, if one is healthy. I infer that it was too much for the Warden of Heaven.”

“So,” I tried, “after we doffed the suits, we were all confused or unconscious for a few minutes. Meaning-in your system of thought-we lost our grip on the Narrative. Stopped tracking it. Whatever faculty of consciousness enables it continuously to do the fly-bat-worm trick-it shut down for a while, there.”

“Yes. And the others regained consciousness in a worldtrack in which you and I are dead.”

“Dead.”

“That is what I told you.”

“So that’s why they left us behind,” I said. “They didn’t leave us behind, because, in their worldtrack, we never even made it here.”

“Yes. Put this on.” He handed me a full-face respirator.

“What of the Fthosian astronomer? Won’t she summon the authorities, or something?”

“She went with Jules. He is talking to her. He has a gift for that kind of thing.”

“So Lio, Arsibalt, Jesry, and Sammann are just wandering around the ship openly, looking for someone to surrender to?”

“Such a worldtrack exists.”

“It’s pretty bizarre.”

“Not at all. Such occurrences are common in the confusion of war.”

“How about this worldtrack? What are the four of them doing in the Narrative that you and I are in?”

“I’m in several,” Fraa Jad said, “a state of affairs that is not easy to sustain. Your questions hardly make it easier. So here is a simple answer. The others are all dead.”

“I don’t wish to abide in a worldtrack where my friends are all dead,” I said. “Take me back to the other one.”

“There is no taking, and there is no back,” Jad said. “Only going, and forward.”

“I don’t want to be in a Narrative where my friends are dead,” I insisted.

“Then you have two choices: put yourself out the airlock, or follow me.” And Fraa Jad pulled the respirator over his face, terminating our conversation. He handed me a fire extinguisher, and took one for himself. Then he shoved off down the corridor.

Now my mind did something absurd, namely, attended to the nuts and bolts of the ship instead of things that were truly important. It was as though some Barb-like part of me had stepped to the fore, elbowed my soul out of the way, and directed all of my energies and faculties toward those things that Barb would find interesting, such as door-latching mechanisms. Subsystems responsible for irrelevancies such as grieving for my friends, fearing death, being confused about the worldtracks, and wanting to strangle Fraa Jad, were starved of resources.

There were many doors, all closed but not locked. This was, according to Jules, the usual state of affairs here. These outer reaches of the ship were divided into separate, independently pressurized compartments so that a meteor strike in one wouldn’t beggar its neighbors. Consequently, one spent an inordinate amount of time opening and closing doors. These were domed round hatches about three feet in diameter, with heavy bank-vault-like latching mechanisms. One opened them by grabbing two symmetrical handles and pulling them opposite ways, which was handy in zero gravity where planting one’s feet and using one’s body weight were not supported by theorical law. The effort always left me panting for breath in Fraa Jad’s wake. One of the questions I had meant to annoy him with had been, Why me? Can’t you do whatever it is you are doing alone, so that I can be in a Narrative where my friends are alive? And maybe this was the answer. I’d been picked out for the same reason that the hierarchs at Edhar had made me part of the bell-ringing team: I was a lummox. I could open heavy doors. It seemed preferable to doing nothing, so I floated ahead of Fraa Jad and applied myself to it. Every time I hauled one open I expected to find myself staring down the muzzle of an Urnudan space marine’s weapon, but there simply weren’t that many people here in the observatory, and when we did finally encounter someone in a corridor, she gasped and got out of our way. The firefighter disguise was so simple, so obvious, I’d assumed it could never work. But it had worked perfectly on the first person we’d met, which probably meant it would work as well on the next hundred.

That corridor led to a spherical chamber that apparently served as the foyer for the whole vertex. We had to pass through it, anyway, to get out of this vertex and reach other parts of the Daban Urnud. As we discovered by trial and error, one of its exits communicated with a very long tubular shaft. “The Tendon,” I announced, when I discovered it. Fraa Jad nodded and launched himself down it.

The stupendous icosahedron and its imposing vertex-citadels had accounted for almost all of my impressions of the ship until now. Their size and their strangeness made it easy to forget that essentially all of the Daban Urnud’s complexity and population lay elsewhere: in the spinning Orbstack. Until now, Fraa Jad and I had been like a couple of barbarians kicking down doors in an abandoned guardhouse on the frontier of an empire. Here, though, we had set out on the road that would take us to the capital. There were a dozen Tendons. Six radiated from each of the mighty bearings at the ends of the Orbstack. The Orbstack was like a monkey using its arms and legs to brace itself in the middle of a packing crate. Sometimes an arm had to push, sometimes it had to pull. It flexed to absorb shocks. It was alive: a bundle of bones that gave strength, muscles that reacted, vessels that transported materials, nerves that communicated, and skin that protected all of the rest. The Tendons had to perform all of the same functions, and so shared much of that complexity. All that Fraa Jad and I could see of this Tendon was the inner surface of a ten-foot-diameter shaft, but we knew from talking to Jules that the Tendon as a whole was more than a hundred feet wide, and crammed with structure and detail hidden from our view-but richly hinted at by a bewilderingly various series of hatches, valve-wheels, wiring panels, display screens, control panels, and signs that shimmered by us as we flew along. Since it was impossible for novices such as we to get aimed perfectly down the center, we strayed from side to side as we went along. Whenever we came in slapping range of a likely-looking handhold we’d give it a bit of abuse and earn some speed, then take a lot of deep breaths while coasting to the next. About halfway along, we encountered a group of four Geometers who, when they saw us coming, grabbed handholds and crouched against the wall to make way. As we flew by, they shouted what I assumed were questions, which we had little choice but to ignore.

The hatch at the end opened onto a domed chamber about a hundred feet across: by far the largest open volume we had yet seen. I knew it had to be the forward bearing chamber. This was confirmed by the fact that it had a navel in its floor, perhaps twenty feet across, and everything that we could see on the other side of it was rotating. We had reached the forward end of the Core. Surrounding but invisible to us was the immense bearing that connected the spinning Orbstack to the non-spinning complex of icosahedron and Tendons that guarded it.

It was a mess. Half a dozen Tendon-shafts were plumbed into this thing via huge portals shot into its domed “ceiling.” Fraa Jad and I had just emerged from one of them. The adjacent one was the focus of a huge amount of activity and attention-it looked like one of those pits in great cities where stocks are traded. This, of course, was the Tendon that led to the World Burner complex, or what was left of it now that the Valers had got to it. People were flying in to, or issuing from, it at a rate of about two per second-it was like watching the entrance of a hornet’s nest in high summer. Most of those going into it were carrying weapons or tools. Some of those coming out were injured. The ingoing and outcoming streams collided in the bearing chamber, and others tried to sort things out, to tell people where to go, what to do, without much result that I could discern, save that they ended up arguing with each other. I was just as happy I couldn’t understand what they were saying. The chaos made it almost too easy for me and Fraa Jad to move around without attracting notice. In fact, my only problem was distinguishing the Thousander from other men in firefighting gear. But after a brief moment of anxiety when I feared I’d lost him, I spied a likely-looking firefighter gazing in my direction and pointing toward what I had begun to think of as the floor of the chamber: the flat surface with the big hole in the middle of it.

The hole was getting smaller.

As Jules had explained, wherever the Daban Urnud’s architects had needed to forge a connection between major parts of the Core, they had used a ball valve, which was just a sphere with a fat hole drilled through the middle, held captive in a spherical cavity bridging the two spaces in question. The sphere couldn’t go anywhere, but it was free to rotate. Depending on how the hole in its middle was aligned, it could allow free passage or form an impregnable barrier. Such a valve was set into the “floor” of this chamber. It was so huge that, at first, I hadn’t seen it for what it was. But now that it had gone into motion, its nature and its function were perfectly obvious. It moved ponderously, but by the time Fraa Jad managed to draw my attention to it, the thing was already about half closed, like an eyeball slowly drifting into sleep.

Fraa Jad planted his feet against a soldier’s backside and shoved off, driving the soldier toward the ceiling and Jad down toward the ball valve. I was already near a sort of ladder or catwalk, which I pushed off against to propel myself after him. When we got to the ball valve, the aperture had narrowed to perhaps three feet at its widest-plenty of room to squeeze through. But we had used up all of our momentum just getting there, and our aim had been miserable. After some feverish banging around we drifted through the aperture and found ourselves hovering in the bore of the sphere, watching the eye at its other end get smaller. There were no handholds that we could use to move ourselves along. If we didn’t reach the other end by the time it closed, we’d be imprisoned until the next time they opened the valve.

I was too out of breath to do much anyway. I aimed my fire extinguisher back the way we’d come and pulled the trigger. The recoil forced it back against me; I took the force with my arms and felt myself tumbling backwards. But I was moving. I slammed into the socket-wall at the end, scrabbled for a handhold on the rim of the hole, and pulled myself through. A second later Fraa Jad squirted through on a snowy plume of fire retardant. I grabbed his ankle, which slowed him down quite a bit. We found ourselves adrift and slowly tumbling at the forward extremity of the two-mile-long, hundred-foot-diameter shaft that ran the length of the Orbstack. We had made it to the Core. And if any of those we’d left behind in the bearing chamber had found our behavior suspicious, they had not been adroit enough to follow us through the ball valve. Smaller hatches-airlocks, made for one person at a time-were planted around it so that people could pass between Core and bearing chamber even when the ball valve was closed. I kept a nervous eye on those, half expecting a space cop to fly out and accost us, but then reasoned that it simply wasn’t going to happen. Jules’s words of a few minutes ago came back to me. What the Valers had done-what we had done-had been the worst military embarrassment these people had suffered in a thousand years. The bomb was still on fire, the disaster only getting started. The Valers might still be alive and fighting. So they weren’t going to make a big deal about a couple of firefighters acting weird.

Our panicky flight through the valve had imbued us with momentum that carried us outward toward the wall of the Core, which was rotating about as fast as the second hand on a clock. This meant that when we drifted into the wall, it was moving past us at a brisk walking pace. This part of the Core wall was covered with a grid with convenient hand-sized holes between the bars, so we did what came naturally and grabbed it. The effect was gentle but inexorable acceleration that made our feet spin out to find purchase on the grid. We were now rotating along with everything else. Here our body weight was less than that of a newborn infant. But it was the most “gravity” we had known for a long time, and took a little getting used to.

We clung to it for a couple of minutes, gasping for air, trying not to black out. Then Fraa Jad, never one to discuss his plans and intentions with his traveling companions, pushed off and glided along the Core wall, headed for the first of the four great Nexi that were spaced evenly along its length. Travel was easier in micro-than in zero gravity, because we slowly “fell” to the Core wall where we could always push off and get another dose of momentum. Available was a sort of rapid transit system, consisting of a moving conveyor-belt-cum-ladder that glided up one side of the Core and down the other. Most of the people we could see-perhaps a hundred, heavily skewed toward soldiers and firefighters-were using it. The rungs were elastic, so that when you grabbed one it didn’t simply jerk your arm from its socket. Tired as I was, I was tempted to have a go, but didn’t want to make a spectacle of myself. Fraa Jad showed no interest. We moved more slowly than those who were using it, which worked to our advantage: some of them shouted questions at us as they glided by, but none was inquisitive enough to jump off and pursue the conversation.

In a few minutes we came to the station in the Core where the forward-most Orbs-One, Five, Nine, and Thirteen-were connected. Each of these stood at the head of a stack of four. So, Orbs One through Four were for the Urnudans. Five through Eight were Troan, Nine through Twelve were Laterran, and the rest Fthosian. By convention, the lowest-number Orb in each stack-the ones that connected here, at the heads of the stacks-were for the highest-ranking members of their respective races. So this Nexus was the most convenient place for the Geometers’ VIPs to meet. From where we were, it didn’t look like much: just four cavernous holes in the wall, the termini of perpendicular shafts leading out to the Orbs. According to Jules, though, if we were to look at it from the outside, we would see that this part of the Core was wrapped in a doughnut of offices, meeting-chambers, and ring-corridors where the Command had its offices. Several hatches in the Core wall hinted at this. But conflict between Pedestal and Fulcrum had led to a division of the Command torus into parts of unequal size. Hatches had been locked, partitions welded into place, guards posted, cables severed.

None of which concerned us very much, since the space we were in served only as a service corridor or elevator shaft, rarely visited or thought about by the Command. Of much greater interest to us were the four huge orifices in the Core wall. As we drifted into the Nexus we were able to gaze into these and see tubular shafts, each about twenty feet in diameter, each leading “down” about a quarter of a mile. At the “bottom” of each was another huge ball valve, currently closed. Beyond each such valve was an inhabited Orb a mile wide.

It wasn’t difficult to identify the shaft leading to Orb One. A large numeral was painted on the Core wall next to it. The numeral was Urnudan, but any sentient being from any cosmos could recognize it as the glyph that represented unity, 1, a single copy of something. I, however, did not have time to linger and contemplate its profound meaning, as Fraa Jad had already located a ladder bracketed to the wall of the shaft, and begun to descend it.

I followed him. Gravity slowly came on as we went. It’s hard to describe how terrible this made me feel. The only thing that kept me from passing out was fear I’d let go of the rungs and fall down on top of Fraa Jad. During the worst spell, a voice drilled into my awareness and made my skull buzz. Fraa Jad had begun to sing some Thousander chant like the one that had kept me awake at the Bazian monastery on the night we had been Evoked. It gave my consciousness something to hold on to, like the steel ladder-rung that I was gripping with my hand: my only hard tangible link to the giant complex spinning around me. And in the same way that the rung kept me from falling, the sound of Jad’s voice in my skull kept my mind from floating away to wherever it had gone when I’d passed out in the observatory and awoken on the wrong worldtrack.

I kept descending.

I was crouching atop a giant steel navel with my head between my knees, trying not to pass out.

Fraa Jad was punching numbers into a keypad mounted to the wall.

The sphere began to rotate beneath me.

“How did you know the code?” I asked.

“I selected a number at random,” he said.

I’d heard only four beeps from the keypad. Only a four-digit number. Only ten thousand possible combinations. So if there were ten thousand Jads in ten thousand branches of the worldtrack…and if I were lucky enough to be with the right one…

Sunlight was shining through the bore of the valve. I flattened myself on it and gazed down on open water, vegetation, and buildings from an altitude of half a mile.

This time, the bore of the valve had ladder-rungs on it. We climbed down them even as the valve was snapping to its final position, and exited onto a ring-shaped catwalk hung from the ceiling of the orb, surrounding the aperture-the oculus at the top of a vast spherical dome, a little sky above a little world. A stairway led up to it. Men with weapons were running up the stairway, intent on saying hello to us. Fraa Jad, seeing this, pulled off his respirator. No point in maintaining the disguise now. I did likewise.

Two soldiers, peering down shotgun barrels, reached the catwalk. One of them moved aggressively toward Fraa Jad. I stepped forward, instinctively, holding up my hands. My attention was drawn to a small silver object in Fraa Jad’s hand-like a jeejah, of all things! The other soldier pivoted toward me and swung the butt of his weapon around, catching me in the jaw. I toppled backward over the rail and felt my old friend, zero gravity, taking me back into its embrace as I went into free fall down the middle of the orb. Something went extremely wrong in my guts. A moment later I heard the boom of a shotgun. Had I been shot? Not likely, given my situation. My vision whited out again, and my viscera caught on fire and melted.

They had shot Fraa Jad. The Everything Killers had been turned on. I had become a nuclear weapon, a dark sun spraying fatal radiance onto the dwellings and cultivated terraces of the Urnudan community below.

We had accomplished our mission.