*Breeding Ground* by Stephen Baxter

Stephen Baxter's most recent novel, _Evolution_, a saga of human origins, is just out from Del Rey. He's now at work on a new trilogy, tentatively called "Homo Superior" and, like "Breeding Ground," set in the Xeelee Universe. Mr. Baxter is also working on two more collaborations with Arthur C. Clarke.

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Blue light burst from her starbreaker pod. Mari threw up her hands.

The pod exploded in her face.

She was hurled backward, landing with a jarring impact against the weapons emplacement's rear bulkhead. Something gushed over her eyes -- something sticky -- blood? With a sudden terror, she scraped at her face.

The emplacement's calm order had been destroyed in an instant, she saw. Alarms howled, insistent. There was screaming all around her, people flailing. The transparent forward bulkhead had buckled inward, and the row of starbreaker pods behind it, including her own, had been crushed and broken open. Charred shadows still clung to some of the stations, and there was a stink of smoke, of burned meat. She had been lucky to have been thrown back, she realized dully.

But beyond the forward bulkhead, the battle was continuing. She saw black extragalactic space laced by cherry-red starbreaker beams, a calm enfilade caging in the bogey, the Snowflake, the misty alien artifact at the center of this assault. The rest of the flotilla hovered like clouds around the action: Spline ships, fleshy scarred spheres, sisters of the living ship in which she rode, each wielding a huge shield of perfectly reflective Ghost hide.

The gravity failed. She drifted away from the wall, stomach lurching. In the misty dark, something collided with her, soft and wet; she flinched.

There was a face in front of her, a bloody mouth screaming through the clamor of the alarm. "Gunner!"

Something snapped back into focus. "Yes, sir."

This was Jarn, a sub-lieutenant. She was bloodied, scorched, one arm dangling; she was struggling to pull herself into a pressure cloak. "Get yourself a cloak, then help the others. We have to get out of here."

Mari felt fear coil beneath her shock. She had spent the entire trip inside this emplacement; here she had bunked, messed, lived; here was her primary function, the operation of a starbreaker beam. Get out? Where to?

"...Academician Kapur first, then Mace. Then anybody else who's still moving..."

"Sir, the action -- "

" -- is over." For a heartbeat, Jarn's shrill voice softened. "Over for us, gunner. Now our duty is to keep ourselves alive. Ourselves, and the Academician, and the wetback. Is that clear?"

"Yes, sir."

"Move it!" Jarn spun away, hauling cloaks out of lockers.

Mari grabbed a cloak out of the smoke-filled air. Jarn was right; the first thing you had to do in a situation like this was to make sure you could keep functioning yourself. The semi-sentient material closed up around her, adjusting itself as best it could. The cloak was too small; it hurt as it tried to enfold her stocky shoulders, her muscular legs. Too late to change it now. There was a sharp tingle at her forehead as the cloak started to work on her wound.

Jarn had already opened a hatch at the back of the emplacement. She was pushing bodies through as fast as she could cram them in. Seeing Mari, she jabbed a finger toward Kapur.

The Academician -- here because he was the nearest thing to an expert on the action's target -- was drifting, limbs stiff, hands clutched in front of his face. Mari had to pull his hands away. His eye sockets were pits of ruin; the implanted Eyes there had burned out.

No time for that. She forced herself to close the cloak over his face. Then she pushed him by main force toward Jarn's open hatchway.

Next she came to Mace, the wetback. He was bent forward over a sensor post. When she pulled him back, she saw that both legs had been crudely severed, somewhere below the knee. Blood pumped out of broken vessels in sticky zero-G globules. His mouth gaped, strands of bloody drool floating around his face.

Her cloak had a medical kit at her waist. She ripped this open now and dug out a handful of gel. Shuddering at the touch of splintered bone and ragged flesh, she plastered the gel hastily over the raw wounds. The gel settled into place, turning pale blue as it sealed vessels, sterilized, dissolved its substance into a blood replacement, started the process of promoting whatever healing was possible. Then she dragged a cloak around Mace and hurled him bodily toward Jarn and the hatch.

Under the alarm, she realized now, the noise had subsided. No more screaming. Nobody left in the emplacement was moving, nobody but her.

Beyond the forward bulkhead, the bogey was beginning to glow internally, pink-white, and subtle structures crumbled. Fleshy Spline hulls drifted across the artifact's complex expanse, purposeful, determined.

But the bulkhead was blistering.

She dived through the hatch. Jarn slammed it closed. Mari felt a soundless explosion. The alarm was cut off at last.

She was in a kind of cave, roughly spherical, criss-crossed by struts of some cartilaginous material. It was dark here, a crimson obscurity relieved only by the glow of the cloaks. She could see portals in the walls of the cave -- not hatchways like decent human engineering, but _orifices_, like nostrils or throats, leading to a network of darker chambers beyond. There was some kind of air here, surely unbreathable. Little motes moved in it, like dust.

When she touched a wall, it was warm, soft, moist. She recoiled.

She was stuck inside the body of a Spline.

* * *

Mari had never forgotten her first view of a Spline ship.

Its kilometers-wide bulk had dwarfed her flitter. It was a rough sphere, adorned by the tetrahedral sigil of free humanity. The hull, of a wrinkled, leathery hide, was punctured by vast navels within which sensors and weapons glittered. In one pit, an _eye_ had rolled, fixing disconcertingly on Mari; she had found herself turning away from its stare.

The Spline -- so went below-decks scuttlebutt -- had once scoured the depths of some world-girdling ocean. Then, unknown years ago, they'd rebuilt themselves. They'd plated over their flesh, hardened their internal organs -- and had risen from their ocean like vast, studded balloons.

What it boiled down to was that Spline ships were _alive_.

On the whole, it was best not to think about it. Cocooned in the metal and plastic of a gun or sensor emplacement, you mostly didn't have to. Now, however, Mari found herself immersed in deep red biological wetness, and her flesh crawled.

Jarn, strapping her damaged arm tightly to her side, watched her with disgust. "You're going to have to get used to it."

"I never wanted to be a wetback. Sir." The wetbacks were the officers and ratings who interfaced between the Spline vessel and its human cargo. Mace, the Navy officer who had been assigned to escort Academician Kapur during the action, was a wetback.

"We're all wetbacks now, gunner." She glanced around. "I'm senior here," she said loudly. "I'm in charge. Gunner, help me with these people."

Mari saw that Jarn was trying to organize the survivors into a rough row. She moved to help. But there was just a handful here, she saw -- eight of them, including Mari and Jarn, just eight left out of the thirty who had been working in the emplacement at the time of the assault.

Here was Kapur, the spindly Academician with the ruined Eyes, sunk in sullen misery. Beside him, Mace drifted in the air, his cloak almost comically truncated over those missing legs. Jarn was working at Mace's waist, trying to dig out equipment from under the cloak's protective grip. Next to Mace were two squat forms, wrapped in misted cloaks, clutching at each other. Round faces peered up at Mari fearfully.

She reached for their names. "Tsedi. Kueht. Right?"

They nodded. They were supply ratings, both male, plump, soft-skinned. They spoke together. "Sir, what happened?" "When will we get out of here?"

Academician Kapur turned his sightless face. "We made a bonfire. A bonfire of wisdom almost as old as the universe. And we got our fingers burned."

The ratings quailed, clutching tighter.

Useless, Mari thought analytically. Dead weight. Rumor had it that they were cadre siblings, hatched in some vast inner-Expansion Conurbation; further rumor had it they were also lovers.

She moved on down the line of cloaked bodies. Two more survivors, roughly wrapped in their cloaks. She recognized Vael, a gunner ranked below herself, and Retto, a sub-lieutenant who had served as CO of the second watch. Retto had been officer of the watch at the time of the attack. Good sailors both, even the officer.

Except that they weren't survivors. She could see that even through the layers of their imperfectly fitting cloaks, which had turned a subtle blue color, the color of death. Mari's heart sank; it would have been good to have these two at her side.

She surveyed her surviving companions with disgust: Jarn, the pompous ass-muncher of a junior officer; Mace, the half-dead wetback; Kapur, the dried-up domehead; the two soft-bodied store-stackers. All that was left, when so many had died.

Jarn glanced up from her work. She had extracted a kit of what looked like hypodermic needles from Mace's waist. "Take their cloaks. Retto's and Vael's."

Jarn was one rank below the CO and his First Officer, with nominal responsibilities for communications. Mari knew her as a prissy idiot who routinely dumped any responsibility downward. And now, in this grim situation, she had issued a stupid order like that. "Sir, they're _dead._"

Kapur turned blindly. A thin, intense, withdrawn man, he wore his head shaven after the ancient fashion of the Commission for Historical Truth, and he had a clutch of bright red vials strapped to his waist: mnemonic fluid, every droplet a backup record of everything that had happened during the action. He said, "I can tell what you're thinking, gunner. Why did such good soldiers have to die, when such a rabble as this has survived?"

"Academician, shut up," Jarn snapped. "Sir. Just _do_ it, gunner. There's nothing to be done for them now. And we're going to need those cloaks." Fumbling one-handed, she began to jab needles into the fleshy wall of the little cavern, squirting in thick blue gunk.

Keeping her face stony, Mari peeled the cloaks off the inert bodies of Vael and Retto. Vael's chest had been laid open, as if by an immense punch; blood and bits of burned meat floated out of the cavity.

Jarn abandoned her needle-jabbing. "The Spline isn't responding." She held up the emptied hypodermics. "This is the way you communicate with a Spline -- in an emergency, anyhow. Chemicals injected into its bloodstream. Lieutenant Mace could tell you better than I can. I think that this Spline must be too badly wounded. It has withdrawn from us, from human contact."

Mari gaped. "We can't control the ship?"

Kapur sighed. "The Spline do not _belong_ to us, to humanity. They are living ships, independent, sentient creatures, who we hire."

The siblings huddled fearfully. The fatter one -- Tsedi -- stared with wide eyes at Jarn. "They'll come to get us. Won't they, sir?"

Jarn's face flickered; Mari saw that she was out of her depth herself, but she was working to keep control, to keep functioning. Maybe this screen-tapper was stronger than Mari had suspected. "I'm a communications officer, remember." That meant that she had a Squeem implant, an alien fish swimming in her belly, her link to the rest of the crew. She closed her eyes, as if tapping into the Squeem's crude group mind. "There is no _they_, rating."

Tsedi's eyes were wide. "They're dead? _All_ of them?"

"We're on our own. Just focus on that."

Alone. Kapur laughed softly. Mari tried to hide her own inner chill.

As if on cue, they all felt a subtle, gut-wrenching displacement.

"Hyperdrive," Mari said.

The siblings clutched each other. "Hyperdrive? Where is it taking us?"

Kapur said, "Wherever it wants. We have no influence. Probably the Spline doesn't even know we are here. This is what you get when your warship has a mind of its own."

Impatiently, Jarn snapped, "Nothing we can do about _that_. All right, we have work to do. We should pool what we have. Med kit, supplies, weapons, tools, anything."

There was precious little. They had the cloaks, plus the two spares scavenged from the bodies of Vael and Retto. The cloaks came with med-kits, half depleted already. There was some basic planet-fall survival gear, carried routinely by the crew: knives, water purification tablets, even lengths of line for fishing.

Jarn rubbed her wounded arm, gazing at the kit. "No food. No water." She glared at Kapur. "You. Academician. You know something about Spline?"

"More than the rest of you, I suspect," Kapur said dryly. "For all that you use them to fly you around the Expansion from one battle to another. But little enough."

"The cloaks will keep us alive for twenty-four hours. We might use the spares to stretch that a little longer. But we need to replenish them. How? Where do we go?"

I wouldn't have thought so far ahead, Mari thought. Again, she was reluctantly impressed by Jarn.

Kapur pressed his fists to his burned-out Eyes. "Inward. The Spline has storage chambers in a layer beneath its hull. I think."

Tsedi said, "If only Lieutenant Mace was conscious. He's the expert. He would _know_ -- "

"But he isn't," Jarn snapped, irritated. "There's just us."

They were silent.

"All right." Jarn looked around, and selected an orifice directly opposite the one they had entered through. "This way," she said firmly. "I'll lead. Academician, you follow me, then you two, Tsedi and Kueht. Gunner, bring up the rear. Here." She thrust one of the knives into Mari's hand. "Keep together."

Kapur asked, "What about Mace?"

Jarn said carefully, "We can't take him. He's lost a massive amount of blood, and I think he may be in anaphylactic shock."

"We take him."

"Sir, you're our priority." That was true, Mari knew. You were always supposed to preserve the Academicians and Commissaries first, for the sake of the knowledge they might bring forward to the next engagement. And if that couldn't be managed, then you retrieved the mnemonic vials the domeheads kept with themselves at all times. Everything else was expendable. Everything and everyone. Jarn said, "We don't have energy to spare for -- "

"We take him." Kapur reached for Mace. Grunting, he pulled the Navy man to him and arranged him on his back, arms around his neck, head lolling, half-legs dangling.

Jarn exchanged a glance with Mari. She shrugged. "All right. You others, get ready."

"I don't like this situation, sir," Mari said, as she gathered up her kit.

"Me neither," Jarn muttered. "The sooner the Expansion takes full control of these Lethe-spawned Spline, the better. In the meantime, just do your job, sailor. Form up. Keep together. Let's go."

One by one, they filed through the orifice, into the crimson-black tunnel beyond. Mari, as ordered, took the rear of the little column, and she watched the dim yellow glow of the others' cloaks glistening from the organic walls.

She couldn't believe that this was happening. But she breathed, she moved, she followed orders; and she seemed to feel no fear. You're in shock, she told herself. It will come.

In the meantime, do your job.

* * *

Without gravity, there was no up, no down. Their only orientation came from the tunnel around them. Its clammy walls were close enough to touch in every direction, the space so cramped that they had to proceed in single file.

The tunnel twisted, this way and that, taking them sideways as much as inward. But with every meter, Mari was descending deeper into the carcass of this wounded Spline; she was very aware that she was crawling like some parasitic larva _under _the skin of a living creature.

What made it worse was the slow going.

Jarn and Mari moved okay, but Kapur blundered blindly, and Tsedi and Kueht seemed unaccustomed to the lack of gravity. The siblings stayed as close to each other as they could get in the confined space, touching and twittering like birds. Mari growled to herself, thinking what the master-at-arms would have said at that.

They couldn't have gone more than a few hundred meters before Mace's cloak turned blue. But Kapur, bathed in a cerulean glow he couldn't see, refused to leave Mace behind. He toiled doggedly on, his inert burden on his back.

Jarn snapped, "I don't have time for this. Gunner, sort it out."

"Sir. How?"

"With the tact and sensitivity you starbreaker grunts are famous for. Just do it. You two, move on." She took the lead again, hustling Tsedi and Kueht behind her.

Mari took her place behind Kapur, at a loss. "...I guess you knew each other a long time, sir."

Kapur turned. "Mace and I? How old are you, gunner?"

"Eighteen standard, sir."

"Eighteen." He shook his head. "I first met Mace before you were born, then. I was seconded here by the Commission, on the failed first contact with the Snowflake."

"Seconded?"

"I was a policeman. As the Expansion grows, the rate of Assimilation itself accelerates, and specialists are rare.... My own brand of forensic intelligence proved functional for the job. My job was to understand the Snowflake. Mace's was to destroy it."

Mari understood the tension. For five thousand years, humanity's rivalry with those majestic rivals, the Galaxy-spanning Xeelee, had fueled the great colonizing push called the Third Expansion -- and it had determined humanity's attitude to the multitudinous alien species it encountered. They called it the Assimilation, the processing of newly contacted alien species on an industrial scale, across a front that now spanned a quarter of the Galaxy's disc and had reached the great globular clusters beyond.

And there they had found the Snowflake.

Human ships had approached one of the oldest stars of all, a sphere of primordial matter hovering in the Galactic halo like a failed beacon. It was dead, choked with iron; carbon dusted its cooling surface.

The artifact humans called the Snowflake surrounded this dwarf, a vast setting for an ancient, faded jewel.

Since the construction of the Snowflake, thirteen billion years had shivered across the swirling face of the Galaxy. So far as anybody knew, the Snowflake had been constructed to observe: simply that, to gather data, as the universe slowly cooled.

_Processing_: contact, conquest, absorption -- or destruction. If Kapur had been able to determine the goals of the Snowflake and its builders, then perhaps those objectives could be subverted to serve human purposes. If not, then the Snowflake had no value.

Mari guessed, "Lieutenant Mace gave you a hard time."

Kapur shook his head. "Mace was a good officer. Hard, intelligent, ambitious, brutal. He knew his job and he carried it out as best he could. I was in his way; that was uncomfortable for me. But I always admired him for what he was. In the end the Snowflake resisted Mace's crude assaults."

"How?"

"You don't survive for thirteen billion years without learning a few tricks, gunner. We were -- brushed aside. It has taken twenty-two years for the Academies to figure out how to deal with the Snowflake. For deal with it we must, of course. Its stubborn, defiant existence is not a direct threat to us, but it is a challenge to the logic of our ideology." Now he smiled. "We corresponded. I followed Mace's career with a certain pride. Do you think it's getting hot?"

"Sir -- "

"When I was assigned to this assault, Mace was seconded to accompany me. He had risen to lieutenant. It galled him to have to become a wetback."

"Sir. Lieutenant Mace is dead."

Kapur drifted to a halt, and sighed. "Perhaps knowing me did him some good too."

Gently, Mari pulled the broken body from Kapur's back. Kapur didn't resist; he drifted to the wall, running his fingers over its moist surface. Mari pulled the cloak off Mace's inert body, but it had been used up by its efforts to keep Mace alive.

She was surprised to learn of a friendship between a straight-and-true Navy man and a domehead. And then Kapur had attempted to haul his friend along with him, even though it must have been obvious that Mace couldn't survive -- even though Kapur, as their passenger Academician, would have been within his rights to demand that the rest of them carry _him _along.

People always surprised you. Especially those without military training and the proper orientation. But then, she had never gotten to know any domeheads before, not before this disaster, today.

She shoved the body back the way they had come, up into the darkness. When she was done, she was sweating. Maybe it _was_ getting hotter in here, as they penetrated deeper into the core of the Spline. "It's done, sir. Now we have to -- "

There was a flash of light from deeper inside the tunnel. And now came a high-pitched, animal scream.

Mari shoved Kapur out of the way and hurled herself down the tunnel.

* * *

It was Tsedi, one of the fat ratings. He looked as if he had been shot in the stomach. The cloak over his fat belly was scorched and blackened, flaking away. Kueht bounced around the cramped tunnel, screaming, eyes bugging wide, flapping uselessly.

Jarn was struggling with one of the spare cloaks. "Help me." Together Jarn and Mari wrapped the cloak around Tsedi's shivering form.

And when she got closer Mari saw that whatever had burned through the rating's cloak had gone on, digging a hole right _into _Tsedi's body, exposing layers of flesh and fat. Inside the hole, something glistened, wet and pulsing -- 

She retched.

"Hold it in," Jarn said, her own voice tremulous. "Your cloak would handle the mess, but you'd smell it forever."

Mari swallowed hard, and got herself under control. But her hand went to the knife tucked into her belt. "Did someone fire on us?"

Jarn said, "Nothing like that. It was the Spline."

"The Spline?"

Kapur was hovering above them, anchored to the wall by a fingertip touch. "Haven't you noticed how hot it has become?"

Jarn said evenly, "I remember hearing rumors about this. It's part of their -- umm, lifecycle. The Spline will dive into the surface layers of a star. Normally, of course, they drop off any human passengers first."

Mari said, "We're inside a _star_? Why?"

Jarn shrugged. "To gather energy. To feed -- to refuel. Whatever. How should I know?"

"And to cleanse," Kapur murmured. "Probably our Spline's damaged outer layers have already been sloughed away, taking what was left of our emplacements with it."

"What about our dead?"

Kapur shrugged sightlessly.

"There was a sunbeam," Jarn said. "Focused somehow."

"An energy trap."

"Probably. Caught this poor kid in the gut. And -- oh, Lethe!"

Tsedi convulsed, blood-flecked foam showing at his mouth, limbs flapping, belly pulsing wetly. Jarn and Mari tried to pin him down, but his flailing body was filled with unreasonable strength.

It finished as quickly as it had started. With a final spasm, he went limp.

Kueht began to scream, high-pitched.

Jarn sat back, breathing hard. "All right. All right. Take the cloak off him, gunner."

"We can't stay here," Kapur said gently. "Not while the Spline bathes in its star."

"No," Jarn said. "Deeper, then. Come on."

But Kueht clung to Tsedi's corpse. Jarn tried to be patient; in the gathering heat she drifted beside the rating, letting him jabber. "We grew up together," he was saying. "We looked after each other in the Conurbation, in the cadres. I was stronger than he was and I'd help him in fights. But he was clever. He helped me study. He made me laugh. I remember...."

Mari listened to this distantly.

Kapur murmured, "You don't approve of family, gunner?"

"There is no such thing as family."

"You grew up in a Conurbation?"

"Navy-run," she growled. "Our cadres were broken up and reformed every few years, as per Commission rules. The way it should be. Not like _this._"

Kapur nodded. "But further from the center, the rules don't always hold so well. It is a big Expansion, gunner, and its edges grow diffuse.... And humanity will assert itself. What's the harm in family?"

"What good is it doing that rating now? It's only hurting him. Tsedi is _dead._"

"You despise such weakness?"

"_They_ lived while good human beings died."

"Good human beings? Your comrades in arms. _Your _family."

"No -- "

"Do you miss them, gunner?"

"I miss my weapon." Her starbreaker. It was true. It was what she was trained for, not this sticky paddling in the dark. Without her starbreaker, she felt lost, bereft.

In the end, Jarn physically dragged Kueht away from the stiffening corpse of his cadre sibling. At last, to Mari's intense relief, they moved on.

* * *

They seemed to travel through the twisting tunnel-tube for hours. As the semi-sentient cloaks sought to concentrate their dwindling energies on keeping their inhabitants alive, their glow began to dim, and the closing darkness made the tunnel seem even more confining.

At last, they came to a place where the tunnel opened out. Beyond was a chamber whose mottled walls rose out of sight, into the darkness beyond the reach of their cloaks' dim glow. Jarn connected a line to a hook that she dug into the Spline's fleshy wall, and she and Mari drifted into the open space.

Huge fleshy shapes ranged around them. Some of them pulsed. Fat veins, or perhaps nerve trunks, ran from one rounded form to another. Even the walls were veined: they were sheets of living tissue and muscle, nourished by the Spline's analogue of blood.

Mari found herself whispering. "Is it the brain?"

Jarn snorted. "Spline don't have brains as we do, tar. Even I know that much. Spline systems are -- distributed. It makes them more robust, I guess."

"Then what _is_ this place?"

Jarn sighed. "There's a lot about the Spline we don't understand." She waved a hand. "This may be a, a factory. An organic factory."

"Making _what?_"

"Who knows?" Kapur murmured. He lingered by the wall, sightless gaze shifting. "We are not the only clients of the Spline. They provide services for other species, perhaps from far beyond the Expansion, creatures of whom we may have no knowledge at all. But not everybody uses the Spline as warships. That much is clear."

"It is hardly satisfactory," Jarn said through clenched teeth, "that we have so little control over a key element of the Expansion's strategy."

"You're right, lieutenant," Kapur said. "The logic of the Third Expansion is based on the ultimate supremacy of mankind. How then can we _share _our key resources, like these Spline? But how could we control them? -- any more than we can control this rogue in whose chest cavity we ride helplessly."

Mari said, "Lieutenant."

Jarn turned to her.

Mari glanced back at Kueht. The rating huddled alone at the mouth of the tunnel from which they had emerged. She made herself say it. "We could make faster progress."

Before Jarn could respond, Kapur nodded. "If we dump the weak. But we are not strangers any more; we have already been through a great deal together. Mari, will _you _be the one to abandon Kueht? And where will you do it? Here? A little further along?"

Mari, confused, couldn't meet Kapur's sightless glare.

Jarn angrily set herself before Kapur, clutching her wounded arm. "You're being unfair, Academician. She's trained to think this way. She's doing her job. Trying to save _your_ life."

"Oh, I understand that, lieutenant. She is the result of ten thousand years of methodical warmaking, an art at which we humans have become rather good. She is polished precision machinery, an adjunct to the weapon she wielded so well. But in _this_ situation, we are all stranded outside our normal parameters. Aren't we, gunner?"

"This isn't getting us anywhere," Jarn snapped. She picked out a patch of deeper darkness on the far side of the chamber. "That way. The way we were heading. There must be an exit. We'll have to work our way around the walls. Mari, you help Kapur. Kueht, you're with me...."

* * *

More long hours.

As its energy faded, Mari's cloak grew still more uncomfortable -- tighter on her muscular body, chafing at armpits and groin and neck. It was actually tiring for her to struggle against its elasticity. And, though she had been able to resist throwing up, the cloak was eventually full of her own sour stink.

Meanwhile, her back ached where she had been rammed against the emplacement bulkhead. That gash on her head, half-treated by the cloak, was a permanent, nagging pain. Mysterious aches spread through her limbs and neck. Not only that, she was _hungry,_ and as thirsty as she had ever been; she hadn't had so much as a mouthful of water since the assault itself.

She tried not to think about how much Kueht was slowing them down, what had transpired in the "factory." But there wasn't much else to think about.

She knew the syndrome. She was being given too much time in her own head. And the wrong kind of thinking was always a bad thing.

They came at last to another chamber.

As far as they could see in their cloaks' failing light, this was a hangar-like place of alcoves and nooks. The bays were separated by huge diaphanous sheets of some muscle-like material, marbled with fat. And within the alcoves were suspended great pregnant sacs of what looked like water: green, cloudy water.

Jarn made straight for one of the sacs, pulled out her knife and slit it open. The liquid pulsed out in a zero-G straight-line jet, bubbling slightly. Jarn thrust a finger into the flow, and read a sensor embedded in her cloaked wrist. She grinned. "Sea water. Earth-like, salty sea water. And this green glop is blue-green algae, I think. We found what we came for." She lengthened the slit. "Each of you pick a sac. Just immerse; the cloaks will take what they need." She showed them how to work nipples in their cloaks that would provide them with desalinated water, even a mushy food based on the algae.

Mari helped Kapur, then clambered inside a sac of her own. She didn't lose much water; surface tension kept it contained in big floating globules that she was able to gather up in her hands. She folded the sac like a blanket, holding it closed over her chest. The water was warm, and her cloak, drinking in nutrients, began to glow more brightly.

"Blue-green algae," she murmured. "From a human world."

"Obviously," Kapur said.

"Maybe this is one of the ways you _pay_ a Spline," Jarn said. "I always wondered about that." She moved around the chamber, handing out vials of an amber fluid. "I think we deserve this. Pass it through your cloak."

Kapur asked, "What is it?"

Mari grinned. "Puhl's Blood." For _My-Khal Puhl,_ the legendary pre-Extirpation explorer of Earth.

"Call it a stimulant," Jarn said dryly. "An old Navy tradition, sir."

Mari sucked down her tot. "How long should we stay here?"

"As long as the cloaks need," Jarn said. "Try to sleep."

That seemed impossible. But the rocking motion of the water and its swaddling warmth seemed to soothe the tension out of her sore muscles. Mari closed her eyes, just for a moment. She thought about her starbreaker station: the smooth feel of the machinery as she disassembled it for servicing, the sense of its clean power when she worked it.

When she opened her eyes, three hours had passed. And Kueht had gone.

* * *

"He must have gone back," Jarn said. "Back to where we left his sibling."

"That was hours back," Mari said. She looked from one to the other. "We can't leave him." Without waiting for Jarn's reaction, she plunged back into the tunnel they had come from.

Jarn hurried after Mari, calling her back. But Mari wasn't about to listen. After a time, Jarn seemed to give up trying to stop her.

Through the factory-like chamber they went, then back along the twisting length of muscle-walled tunnel.

...Why am I doing this?

Kueht was still fat, useless, and weak; before the disaster, Mari wouldn't have made room for him in the corridor. All her training and drill, and the Expansion's Druz Doctrine that underpinned them, taught that people were not of equal worth. It was an individual's value to the species as a whole that counted: nothing more, nothing less. And it was the duty of the weak to lay down their lives for the strong, or the valuable.

But it wasn't working out like that. When it came down to it, Mari just couldn't abandon even a helpless, useless creature like Kueht; she couldn't be the one to leave him behind, just as Kapur had said. _Humanity will assert itself...._

You're still thinking too much, gunner.

At last, they reached the place where Mari had jammed Tsedi's burned body. Kueht was here, sprawled over his sibling. They pulled at Kueht's shoulders, turning him on his back. His cloak flapped open. His face was swollen, his tongue protruding and blackened.

Mari said, "Kapur talked about opening our cloaks. Maybe that gave him the idea."

"It must have been hard," Jarn said. "The cloak would have resisted being opened; it is smart enough to know that it would kill its occupant if it did. And asphyxiation is a bad way to die." She shrugged. "He told us he didn't want to go on without Tsedi. I guess we just didn't believe it."

Mari shook her head, unfamiliar emotions churning inside her. Here were two comical little fat men, products of some flawed cadre somewhere, helpless and friendless save for each other. And yet Kueht had been prepared to die rather than live without the other. "_Why_?"

Jarn put her hand on Mari's arm; it was small over Mari's bunched bicep.

They paused to strip Kueht of his cloak. Even now, Mari realized, Jarn was thinking ahead, planning the onward journey.

They made good speed back the way they had come, back to where Kapur was waiting. That was because they had lost the weak and slow after all, Mari reflected. It wasn't a thought that gave her any pleasure.

* * *

"We could just stay here," Jarn said. "There is food. We could last a long while."

Jarn seemed to have withdrawn into herself since the loss of Kueht. Maybe exhaustion was bringing out her core character. She was, after all, just a screen-tapper.

"You've done well," Mari said impulsively.

Jarn looked at her, startled.

"No," Kapur said. "We have to plan for the possibility of rescue. Anything else is futile, simply waiting to die."

Jarn said, "We're stuck inside a Spline warship, remember. Epidermis like armor."

Kapur nodded. "Then we must go to a place where the epidermis can be penetrated."

"Where?"

"The eyes. That's the only possibility I can think of."

Jarn frowned. "How will we find our way to an eye?"

"A nerve trunk," said Mari. Jarn looked at her. Mari said defensively, "Why not? Sir. Every eye must have an optic nerve connecting it to the rest of the nervous system. Or something like it."

Kapur laughed out loud.

Jarn shook her head. "You keep springing surprises on me, Mari."

They filled up the spare cloaks with sea water. Then, each of them trailing a massive, sluggish balloon by a length of rope, they formed up -- Jarn leading, Kapur central, Mari bringing up the rear.

As they left the chamber, mouth-like nozzles puckered from the walls and began to spew sprays of colorless liquid. Mari's cloak flashed a warning. Stomach acid, she thought. She turned away.

Once they were in motion, the inertia of her water bag gave Mari little trouble, but when the tunnel curved, she had some work to do hauling the bag around corners and giving it fresh momentum. But she worked with a will. Physical activity: better than thinking.

In some places, the tunnels were scarred: once damaged, now healed. Mari remembered more scuttlebutt. Some of the great Spline vessels were very old, perhaps more than a million years old, according to the domeheads. And they were veterans of ancient wars, fought, won, and lost long before humans had even existed.

They had been moving barely half an hour when they came to another chamber.

This one was something like the "factory." A broad open chamber criss-crossed by struts of cartilage was dominated by a single pillar, maybe a meter wide, that spanned the room. It was made of something like translucent red-purple skin, and Mari made out fluid moving within it: blood, perhaps, or water. And there were sparks, sparks that flew like birds.

Kapur sniffed loudly. "Can you smell that?" Their cloaks transmitted selective scents. "Ozone. An electric smell."

Jarn's water bag, clumsily sealed, was leaking; Mari had been running into droplets all the way up the tunnel. But now she saw that the droplets were _falling -- _drifting away from Jarn, following slowly curving orbits, falling in toward the pillar that dominated the center of the room.

Jarn, fascinated, followed the droplets toward the pillar.

Something passed through Mari's body, a kind of clench. She grunted and folded over.

"_Oh,_" said Kapur. "That was a tide. Lethe -- "

Without warning, he hurled himself forward. He collided clumsily with Jarn, scrabbled to grab her, and spun her around. His momentum was carrying the two of them toward the pillar. But he tried to shove her away.

"No, you don't, sir," Jarn grunted. With a simple one-armed throw, she flipped him back toward Mari. But that left her drifting still faster toward the pillar.

Kapur scrabbled in the air. "You don't understand."

"Hold him, gunner." Behind Jarn, Mari saw, those water droplets had entered tight, whirling orbits, miniature planets around a cylindrical sun. Jarn said, "We haven't brought him all this way to -- "

And then she folded.

As simple as that, as if crumpled by an invisible fist. Her limbs were thrust forward, her spine and neck bent over until they cracked. Blood and other fluids, deep purple, flooded her cloak, until that broke in turn, and a gout of blood and shit sprayed out.

Mari grabbed Kapur's bent form and threw her body across his, sheltering him from the flood of bodily fluids.

Kapur was weeping, inside his cloak. "I heard it. I _heard _what happened to her."

"What -- ?"

"This is the hyperdrive chamber. Don't you see? Inside a Spline, even a star drive grows organically. Oh, you are seeing miracles today, gunner. Miracles of the possibilities of life!"

"We have to get you out of here."

He straightened, seeming to get himself under control. "No. The lieutenant -- "

Mari shrieked into his face, "She's dead!" He recoiled as if struck. She forced herself to speak calmly. "She's dead, and we have to leave her, as we left the rest. I'm in charge now. Sir."

"The Squeem," he said evenly.

"What?"

"Jarn's implant. If we're to have any chance of rescue, we need it.... Once the Squeem conquered the Earth itself. Did you know that? Now they survive only as unwilling symbiotes of mankind...."

Mari glanced back at Jarn's body, which was drifting away from the pillar. She seemed to have been compressed around a point somewhere above her stomach. Her center of gravity, perhaps. "I can't."

"You have to. I'll help." Kapur's voice was hard. "Take your knife."

* * *

They traveled on for perhaps a day.

Mari's cloak began to fail, growing cloudy, stiff, confining. Kapur moved increasingly slowly and feebly, and, though he didn't complain or even ask, he needed a lot of help. It seemed that he had been wounded somehow, maybe internally, by the shock that had killed Jarn. But there wasn't anything Mari could do about that.

Once, the tunnel they were using suddenly flooded with a thick gloopy liquid, crimson flecked with black. Blood maybe. Mari had to anchor them both to the wall; she wrapped her arms around Kapur and just held him there, immersed in a roaring, blood-dark river, until it passed.

At last, they found an eye.

It turned out to be just that: an _eye_, a fleshy sphere some meters across. It swiveled, this way and that, rolling massively. At the back was a kind of curtain of narrow, overlapping sheets -- perhaps components of a retina -- from which narrower vine-like fibers led to the nerve bundle they had followed. Mari parted the fibers easily. A clear fluid leaked into the general murk.

She pulled Kapur into the interior of the eye. It was a neat spherical chamber. She lodged Kapur against the wall. She found places to anchor their bundles of water, and the scrap of cloak within which swam the Squeem, the tiny alien not-fish that had inhabited Jarn's stomach.

Unlike the tunnels and chambers they had passed through, there were no shadows here, no lurking organic shapes; it was almost cozy.

She pushed at the forward wall. Her hand sank into a soft, giving, translucent surface. A lens, maybe. But beyond there was only veined flesh. "If this is an eye, why can't I see out?"

"Perhaps the Spline has closed its eyes."

The floor under Mari seemed to shudder; the clear fluid pulsed, slow waves crossing the chamber, as the eye swiveled. "But the eye is moving."

Kapur grinned weakly. "Surely Spline dream."

Then the Spline eyelid opened, like a curtain raising. And, through a dense, distorting lens, Mari saw comet light.

* * *

They were deep within a solar system, she saw. She could tell because the comet had been made bright by sunlight. Its dark head was obscured by a glowing cloud, and two shining tails streaked across the black sky, tails of gas and dust.

To Mari, it was a strange, beautiful sight. In most Expansion systems, such a comet wouldn't be allowed to come sailing so close to a sun, because of the danger to the inhabitants of the system, and of the comet itself -- all that outgassing would make the nucleus a dangerous place to live.

But she saw no signs of habitation. "I don't get it," she said. "I don't see any lights. Where are the people?... Oh."

Kapur turned when he heard her gasp.

Ships came sailing out of the glare of the comet's diffuse coma: great fleshy ships, Spline ships, a dozen of them, more. She peered, seeking the green sigil of humanity, the telltale glitter of emplacements of weapons and sensors; but she saw nothing but walls of hardened flesh, the watery glint of eyes. This flotilla was moving like none she had seen before -- coordinated, yes, but with an eerie, fluid grace, like a vast dance. Some of the Spline were smaller than the rest, darting little moons that orbited the great planets of the others.

And now they were gathering around the comet core.

"They are grazing," she said. "The Spline are grazing on the comet."

Kapur smiled, but his face was grey. "This is not a flotilla. It is a -- what is the word -- it is a _school._"

"They are wild Spline."

"No. They are simply Spline."

Now the school broke and came clustering around Mari's ship. Huge forms sailed across her vision like clouds. She saw that the smaller ones -- infants? -- were nudging almost playfully against her Spline's battered epidermis. It was a collision of giants -- even the smallest of these immature creatures must have been a hundred meters across.

And now the Spline rolled. Her view was swiveled away from the comet, across a sky littered with stars, and toward a planet.

It was blue: the blue of ocean, of water, the color of Earth. But this was not a human world. It was swathed in ocean, a sea broken only by a scattered litter of gleaming ice floes at the poles, and a few worn, rusty islands. She could see features on the shallow ocean floor: great craters, even one glowing pit, the marks of volcanism. An out-of-view sun cast glittering highlights from that ocean's silvery, wrinkled hide, and a set of vast waves, huge to be visible from this altitude, marched endlessly around the water-world.

And now she saw a fleet of grey-white forms that cut through the ocean's towering waves, leaving wakes like an armada of mighty ships, visible even from space.

"Of course," Kapur said, his voice a dry rustle, as she described this to him. "It must be like this."

"What?"

"The home world of the Spline. The breeding ground. We knew they came from an ocean. Now they swim through the lethal currents of space. But biology must not be denied; they must return here, to their original birthing place, to breed, to continue the species. Like sea turtles who crawl back to the land to lay their eggs." Kapur folded on himself, tucking his arms into his chest. "If only I had my Eyes!... I often wondered _how _the Spline made that transition from ocean to vacuum. As giant ocean-going swimmers, they surely lacked limbs, tools; there would be no need for the sort of manipulative intelligence that would enable them to redesign themselves. There must have been others involved -- don't you think? Hunters, or farmers. For their own reasons, _they _rebuilt the Spline -- and gave them the opportunity to rebel, to take control of their destiny."

"Academician," Mari said hesitantly. "I don't recognize the stars. I don't see any sign of people. I never heard of a world like this."

"Yes?"

"What part of the Expansion are we in?"

He sighed. "Nobody has seen the home world of the Spline before. Therefore we can't be in the Expansion. I'm afraid I have no idea where we are." He coughed, feebly, and she saw that he was sweating.

It was getting hot.

She glanced out of the window-lens. That blue world had expanded so that it filled up her window, a wall of ocean. But the image was becoming misty, blurred by a pinkish glow. Plasma.

"I think we're entering the atmosphere."

"The Spline is going home."

Now the glow became a glaring white, flooding the chamber. The temperature was rising savagely, and the chamber walls began to shudder. She found herself pulled to the floor and pressed deep into yielding tissue.

I'm not going to live through this, she thought. It was the first time she had understood that, deep in her gut. And yet she felt no fear: only concern for Kapur. She cradled him in her arms, trying to shield him from the deceleration. His body felt stick-thin. He gasped, his face working from pain from which she couldn't save him. Nevertheless she tried to support his head. "There, there," she murmured.

"Do you have any more of that Puhl blood?"

"No. I'm sorry."

"Pity...." He whimpered, and tried to raise his hands to his ruined Eyes.

He had never once complained of that injury, she realized now, even though the agony must have been continual and intense. There are different sorts of strength, she thought. She felt as if her head was full of boulders: huge thoughts, vast impressions that rattled within her skull, refusing her peace. "Lieutenant Jarn turned out to be a good officer. Didn't she, sir?"

"Yes, she did."

"I never liked her, before. But she sacrificed her life for you."

"That was her duty. You would have done the same."

"Yes," said Mari doggedly, "but _you _tried to save _her. _Even though you didn't have to. Even though you would have been killed yourself in the process."

He tried to turn his head. "Gunner, I sense that you believe that you have failed, because you aren't dead yet. Listen to me now. You haven't failed. In the end, what brought us so far was not your specialist training, but deeper human qualities of courage, initiative, endurance. Empathy. In the end, it will be those qualities that will win this war, not a better class of weapon. You should be proud of yourself."

She wasn't sure about that. "If I ever did get out of this I'd have to submit myself for re-orientation."

"The Commission would have its work cut out, I think -- Ah." His face worked. "Child." She had to bend to hear him. He whispered, "Even now, my wretched mind won't stop throwing out unwelcome ideas. You still have a duty to perform. _Remember._"

"Remember?"

"You saw the stars. Given that, one could reconstruct the position of this world, this Spline home. And how valuable that piece of information would be! It would be the end of the free Spline," he said. "What ... a pity. But I am afraid that we have a duty. Tell them what you saw."

"Sir -- "

He tried to grasp her arm, his ruined face swiveling. "_Tell_ them." His back arched, and he gasped. "_Oh._"

"No!" she said, shaking him.

"I am sorry, gunner Mari. So sorry." And he exhaled a great gurgling belch, and went limp.

She continued to cradle Academician Kapur, rocking him like a child, as the homecoming Spline plunged deeper into its world's thick atmosphere.

But as she held him, she took the vials of mnemonic fluid from his waist, and drank them one by one. And she took the Squeem from its cloak bag -- it wriggled in her fingers, cold and very alien -- and, overcoming her disgust, swallowed it down.

In the last moments, the Spline's great eyelid closed.

* * *

Accompanied by Lieutenant-Commander Erdac, Commissary Drith stepped gingerly through the transfer tunnel and into the damaged Spline eye. Drith's brow furrowed, sending a wave of delicate creases over her shaved scalp. It was bad enough to be immersed _inside _the body of a living creature like this, without being confronted by the gruesome sight the salvage teams had found here. Still, it had been a prize worth retrieving.

Erdac said, "You can see how the Squeem consumed this young gunner, from inside out. It kept alive that way, long enough anyhow for it to serve as a beacon to alert us when this Spline returned to service in human space. And there was enough of the mnemonic fluid left in the gunner's body to -- "

"A drop is sufficient," Drith murmured. "I do understand the principle, Commander."

Erdac nodded stiffly, his face impassive.

"Quite a victory, Commander," Drith said. "If the breeding ground of the Spline can be blockaded, then the Spline can effectively be controlled."

"These two fulfilled their duty in the end."

"Yes, but we will profit personally from this discovery."

He looked down at the twisted bodies and poked at them with a polished toecap. "Look how they're wrapped around each other. Strange. You wouldn't expect a dry-as-a-stick Academician and a boneheaded Navy grunt to get so close."

"The human heart contains mysteries we have yet to fathom, Commander."

"Yeah. Even with the mnemonic, I guess we'll never really know what happened here."

"But we know enough. What else matters?" Drith turned. "Come, Commander. We both have reports to file, and then a mission to plan, far beyond the Expansion's current limits ... quite an adventure!"

They left, talking, planning. The forensic teams moved in to remove the bodies. It wasn't easy. Even in death they were closely intertwined, as if one had been cradling the other.

Copyright (C) 2002 by Stephen Baxter.