Manifold: Space

by Stephen Baxter

  After a while the huts became sparser, until they reached a place where there were no well-defined roads, no construction. The center of the plateau – maybe a kilometer in diameter and fringed by huts – was deserted: just bare rock and lifeless soil, free of grass, bushes, insects or bird song. Even the breeze from Lake Victoria seemed suppressed here.

  It looked, he thought, as if a neutron bomb had gone off.

  They marched on into this grim terrain. Nemoto was silent, her resentment apparent in every gesture and step.

  Malenfant had been ill during the night and hadn't gotten much sleep. He was feeling queasy, shivering. And the landscape didn't help. The ground here was like a little island of death in the middle of this African ocean of life.

  At last they reached the heart of the central plain. They came to a wide, deep well set in the ground. There were steps cut into the rock, spiraling into the ground around the cylindrical inner face of the well. In the low light of the morning Malenfant could see the steps for the first fifty meters or so, beyond that only darkness.

  Nemoto began to clamber down the steps. She walked like the stiff old woman she had become, her gaudy court plumage incongruous in the shadows. Malenfant followed more slowly.

  He wished he had a gun.

  Within a few minutes they'd come down maybe thirty meters – the open mouth of the well was a disc of blue sky, laced with high clouds – and Nemoto rapped on a wooden door set in the wall.

  The door opened. Beyond, Malenfant saw a lighted chamber, a rough cube dug out of the rock, lit up by rush torches. At the door stood one of the Kabaka's guards. He was a pillar of bone and muscle, overlaid by fat and leathery skin. Nemoto spoke briefly, and the guard, after a hostile inspection of Malenfant, let them through.

  The room was surprisingly large. The heat was intense, and the smoke from wall-mounted torches was thick, despite air passages cut into the walls. But the smoke couldn't mask the sweet stenches of vomit, of corrupt and decaying flesh. Malenfant grabbed a handkerchief from his pocket and held it over his face.

  Pallets of wood and straw, covered by grimy blankets, were arranged in rows across the floor, and Malenfant had to step between them to make his way. Maybe half of the pallets were occupied. The eyes that met Malenfant's flickered with only the dullest curiosity.

  The invalids all seemed wasted by the disease that had afflicted de Bonneville, to a greater or lesser degree. Patches of skin were burned to blackness, and there were some people with barely any skin left at all. Malenfant saw heads free of hair – even eyelashes and eyebrows were missing as if burned off – and there were limbs swollen to circus-freak proportions, as well as broken and bleeding mouths and nostrils. There were attendants here, but as far as Malenfant could see they were all Uprights: Homo Erectus, reconstructed genetic fossils, tall and naked and golden furred, moving between the sick and dying. There seemed to be no real medical care, but the Uprights were giving out water and food – some kind of thin soup – and they murmured comfort in their thin, consonant-free voices to the ill.

  It was like a field hospital. But there had been no war: and besides there were women and children here.

  At last Malenfant found de Bonneville. He lay sprawled on a pallet. He stared up, his face swollen and burned beyond expression. "Malenfant – is it you? Have you any beer?" He reached up with a hand like a claw.

  Malenfant tried to keep from backing away from him. "I'll bring some. De Bonneville, you got worse. Is this a hospital?"

  He made a grisly sound that might have been a laugh. "Malenfant, this is... ah... a dormitory. For the workers, including myself, who service the yellow-cake."

  "Yellow-cake?"

  "The substance that fuels the Engine of Kimera..." He coughed, grimacing from the pain of his broken mouth, and shifted his position on his pallet.

  "What's wrong with you? Is it contagious?"

  "No. You need not fear for yourself, Malenfant."

  "I don't," Malenfant said.

  De Bonneville laughed again. "Of course you don't. Indeed, nor should you. The illness comes from contact with the yellow-cake itself. When new workers arrive here, they are as healthy as you. Like that child over there. But within weeks, or months – it varies by individual, it seems, and not even the strongest constitution is any protection – the symptoms appear."

  "De Bonneville, why did they send you back here?"

  "I have a propensity for offending the Kabaka, Malenfant, most efficiently and with the minimum of delay. So here I am again."

  "You're a prisoner?"

  "In a way. The guards ensure that the workers are kept here until such time as the Kimera sickness takes hold of their limbs and complexion. Then one is free to wander about the town without hindrance." He touched his blackened cheeks; a square centimeter of skin came loose in his fingers, and he looked at this latest horror without shock. "The stigmata of Kimera's punishment are all too obvious," he said. "None will approach a yellow-cake worker, and certainly none will feed or succor him. And so there is no alternative, you see, but to return to the Engine, where at least food and shelter is provided, there to serve out one's remaining fragment of life..."

  "Who is Kimera?"

  "Ah, Kimera!" he said, and he threw back his ravaged head. Kimera, it turned out, was a mythical figure: a giant of Uganda's past, so huge that his feet had left impressions in the rocks. "He was the great-grandson of Kintu, the founder of Uganda, who came here from the north; and it was Wanpamba, the great-great-grandson of Kimera, who first hollowed out the hill of Rubaga and entombed the soul of Kimera here..." And so forth: a lot of poetical, mythical stuff, but little in the way of hard fact. "You know, they had to reconstruct these old myths from the last encyclopedias, for the people had forgotten them – but don't let the Kabaka hear you say it..." De Bonneville's eyes closed, and he sank back, sighing.

  Nemoto, nervous, plucked at Malenfant's sleeve. Her mime was obvious. Time was up; they should go; this was an unhealthy place.

  Malenfant didn't see what choice he had. All the way out, Malenfant was aware of de Bonneville's gaze, locked on his back.

  Outside the grisly dormitory, Malenfant peered into the deeper blackness of the well. "Nemoto, what's down there?"

  "Danger. Death. Malenfant, we must leave."

  "It is the Engine of Kimera, whatever the hell that is. You know, don't you? Or you think you know. Rubaga has the only significant radiation-anomaly signature on Earth..."

  Her face was as expressionless as her Moon-rock Buddha's. "If you want to fry your sorry skin, Malenfant, you can do it by yourself." She turned and walked off, leaving him with the guard.

  The guard looked at him quizzically. Malenfant shrugged, and pointed downward.

  He walked to the ledge's rim – a sheer drop into darkness, no protective rail of any kind – and leaned over. There seemed to be a breeze blowing down from above, rustling over the back of his neck, into the pit itself, as if there were a leak in the world down there. Now, he couldn't figure that out at all. Where was the air going? Was there a tunnel, some kind of big extractor?

  The only light came from the flames of rush torches, flickering in that downward breeze, and Malenfant's impressions built up slowly.

  He made out a large heap of ore, crushed to powder, contained within a rough open chamber hollowed out of the stone. Maybe that ore was the yellow-cake de Bonneville had talked about. Long spears of what appeared to be charcoal – like scorched tree trunks – stuck out of the heap from all sides and above. Water was carried in channels in the walls and pipes of clay, and poured into the heart of the heap. He guessed the heap contained a hundred tons of yellow-cake; there were at least forty charred trunks protruding from it.

  The chamber was full of people.

  There were a lot of tall Uprights, many squat habilines, and some Waganda: men, women, and children who limped doggedly through the darkness, intense heat, and live steam, serving the heap as if it were some ugly god. They hauled at the cha
rcoal trunks, drawing them from the yellow-cake, or thrust them deeper inside. Or else they hauled simple wheelbarrows of the yellow-cake powder to and from the heap, continually replenishing it. Their illness was obvious, even from here. Peering down from far above, it was like looking over some grotesque anthill, alive with motion.

  The heap was intensely hot – Malenfant could feel its heat burning his face – and the water emerged from the base of the heap as steam, which roared away through a further series of pipes. There was a lot of leakage, though, and live steam wreathed the heap's ugly contours.

  The principle was obvious. The heap was an energy source. The steam produced by the heap must, by means of simple pumps and other hydraulic devices, power the various gadgets he'd witnessed: Mtesa's ascending throne, the fountains. Maybe the water that passed through the system was itself pumped up from some deeper water table by the motive power of the steam.

  There had to be a lot of surplus energy, though.

  And now he made out a different figure, emerging from some deeper chamber at the base of the pit. It was a woman. She looked like a cross between a habiline and an Upright: big frame, thick neck, head thrust forward. She was wearing a suit, of some translucent plastic, that enclosed her body, hands, and head. She was familiar to him, from a hundred TV shows and school-book reconstructions. She was Neandertal: another of humanity's lost cousins.

  Holy shit, he thought.

  There was a flash of light from the hidden chamber, from some invisible source.

  It was blue, a shade he recognized.

  Neandertals, and pressure suits, and electric blue light. Unreasoning fear stabbed him.

  He got out of there as fast as he could.

  The next day Malenfant visited de Bonneville again. Malenfant brought him a small bottle of pombe; de Bonneville fell on this avidly, jealously hiding it from the other inmates of the ward. Malenfant wanted to ask about the Engine, but de Bonneville had his own tale to tell.

  "Listen, Malenfant. Let me tell you how I came to this pass. It started long before you arrived..."

  De Bonneville told him that a gift had arrived for Mtesa, the emperor, from Lukongeh, king of the neighboring Ukerewe. There had been five ivory tusks, fine iron wire, six white monkey skins, a canoe large enough for fifty crew – and Mazuri, an Upright girl, a comely virgin of fourteen, a wife suitable for the Kabaka.

  "Mtesa's harem numbers five hundred. Mtesa has the pick of many lands; and many of the harem are, as I can testify, of the most extraordinary beauty. But of them all, Mazuri was the comeliest."

  "I think I saw her in the palace. Mtesa likes her."

  "She has –" De Bonneville waved his damaged hands in a decayed attempt at sensuality. "– she has that animal quality of the Uprights. That intensity. When she looks you in the eyes, you see direct into her primeval soul. Do you know what I'm talking about, Malenfant?"

  "Yes. But I'm a hundred years old," Malenfant said wistfully.

  "Mazuri was young, impetuous, impatient at her betrothal to Mtesa – a much older man, and lacking the vigor of her own kind..."

  De Bonneville fell silent, in a diseased reverie.

  "Tell me about the Engine."

  "The Waganda say the yellow-cake is suffused with the Breath of Kimera," de Bonneville said, dismissive. "It is the Breath that supplies the heat. But a given portion of yellow-cake is eventually exhausted of its Breath, and we must extract and replace the cake, continually."

  "What about the tree trunks?"

  "We must insert and extract the trunks, according to the instructions of –" He quoted a term Malenfant didn't know, evidently a sort of foreman. "The Breath is invisible and too rapid to have much effect – except on the human body, apparently, which it ravages! The tree trunks are inserted to slow down the Breath from the heart of the heap. Do you see? Then it gets to work on the rest of the yellow-cake. And that is, in turn, encouraged to produce its own Breath in response. It's like a cascade, you see. But the Waganda can control this, by withdrawing their charred trunks; this has the effect of allowing the Breath to speed up, and escape the heap harmlessly..."

  A cascade, yes, Malenfant thought. A chain reaction.

  "And the water? What's that for?"

  "The emission of the Breath is associated with great heat – which is the point of the Engine. Water flows through the hillside, through the engine. The water is a cooling agent, which carries off this heat before any damage is done to the Engine. And the heat, of course, turns the water to steam, which in turn is harnessed to drive Mtesa's various toy devices and fripperies..." Malenfant heard how de Bonneville's voice slowed as he said that, as if some new idea was coming to him.

  To Malenfant, it all made sense.

  Twentieth-century nuclear-fission piles had been simple devices. They were just heaps of a radioactive material, such as uranium, into which reaction-controlling moderators, for example carbon rods, were thrust. Technical complexity only came if you cared about human safety: shields, robot devices to control the moderators, a waste-extraction process, and so forth. If you didn't care about wasting human life, a reactor could be made much more simply.

  With a little instruction, a tribe of Neandertals could operate a nuclear reactor. A bunch of children could. Especially if you didn't care about safety.

  "It's the Breath that makes you ill," he said.

  "Indeed."

  "Why not others? Why not Mtesa himself?"

  "The Breath is contained by the hundreds of meters of rock within which the Engine is housed. But, though it is not spoken of, there is much illness among the general population; and there are elaborate taboos about associating too closely with products of the Engine – you shouldn't drink the water that has circulated through the yellow-cake, for instance."

  Malenfant remembered how Nemoto had warned him against inserting his hands in Mtesa's fountains. He felt, now, a renewed itching in his own damaged skin.

  Shit, he thought. I must have taken a dose myself.

  De Bonneville waved his gnarled hands. "The Engine is clearly very ancient, Malenfant. The Waganda's legend says it was constructed by an old king, seventeen generations before our own glorious Mtesa. It seems to me the Waganda have learned how to control their crude device, not by proceeding from a body of established knowledge as we might have done, but by trial and error over generations – and expensive trial and error at that. Expensive in human life, I mean!" But he was tiring, and losing interest. "Let me tell you of Mazuri..."

  "You screwed the king's favorite wife. You asshole, de Bonneville."

  "I tried to put her aside, when I left Rubaga to meet you. But when I returned, full of pombe and the excitement of the hunt, there she was... Ah, Malenfant, those eyes, that skin, that mouth..."

  He was found out. Mtesa's fury had been incandescent. De Bonneville was expelled from his position in court – dragged, by a rope around his neck, by Mtesa's enthusiastic Lords of the Cord, and subjected to fifty blows with a stick, a punishment severe enough to lame him – and then banished to the lowliest position of Rubaga society: to work in the yellow-cake Engines, buried deep within the hillside.

  De Bonneville grasped Malenfant's arm with his ruined, clawlike hands. "It was all a trap, Malenfant. One accumulates enemies so easily in such a place as this! And I... I was always impetuous rather than careful... I was led into a trap, and I have been destroyed! Seeing you now, a traveler, makes me understand anew how much has been robbed from me by these savages of the future. But –"

  "Yes?"

  His blue eyes gleamed in his blackened ruin of a face. "But de Bonneville shall have his revenge, Malenfant. Oh, yes! His determination is sweet and pure..."

  He confronted Nemoto.

  "Nemoto, you know what the Engine is, don't you? It's a nuclear pile. A fucking nuclear pile."

  Nemoto shrugged. "It's just a heap. Maybe a hundred tons of 'yellow-cake' – which is a uranium ore – with burned tree stumps used as graphite moderators. It was a geological a
ccident: yellow-cake seams inside this hollow mountain, and some natural water stream running over the pile, cooling it..."

  Natural nuclear reactors had formed in various places around the planet, where the geological conditions had been right. What was needed was a concentration of uranium ore, and then some kind of moderator. The function of the moderator was to slow down the neutrons, the heavy particles emitted by decaying uranium atoms. A slowed-down neutron would impact with another atomic nucleus and make that decay, and the neutron products of that event would initiate more decays – on and on, in the cascade of collapsing nuclei the physicists called a chain reaction.

  Under Rubaga's mountain, the action of water, over billions of years, had washed uranium ore from the rock and caused it to collect in seams at the bottom of a shallow sea. The uranium had then been overlaid by inert sand, and the rocks compressed and uplifted by tectonic forces, the uranium further concentrated by the slow rusting of surrounding rocks in the air. Thus had been created seams of uranium, great lenticular deposits, two or three meters thick and perhaps ten times as wide, under their feet, right here.

  At first there had been no chain reaction. But then water and organic matter, seeping into cracks in the uranium seams, had served as primitive moderators, slowing the neutrons down sufficiently for the reaction process to start.

  "The reaction probably started as a series of scattered fires in concentrations of the uranium ore," Nemoto whispered. "Then it spread to less rich areas nearby. It was self-controlling; as the water was boiled by the reaction's heat it would be forced out of the rock – and the reaction would be dampened, until more water seeped back from the surface layers above, and the reaction could begin again." She smiled thinly. "And that is what the Neandertal community here discovered. It took them a couple of centuries, but they learned to tinker with the process, inserting burned wood – graphite – as secondary moderators..."

  The workers in the pile maintained it with their bare hands. At times the workers had to haul heaps of yellow-cake from one part of the pile to another; or they mixed the yellow-cake, by hand, with other moderator compounds; or they cleared out the coolant-water pipes – the small fingers of children were well adapted for that particular chore. And as well as the regular operation of the pile, they had to cope with accidents, types of which Nemoto listed in the local language: leakages, spill-outs, crumbles, hot beds, slaps.