Shell A.D. 4,101,214 "I've found a bird from the Shell—a bird from space!" Allel ran into the village bursting with her news, her baggy bark shirt flapping. But nobody was impressed. She couldn't understand it. Younger children turned back to their games in the dust. Her mother, Boyd, absently cuffed Allel's fourteen-year-old head. "Don't bother me," she growled, and went about her business. Boyd's face was a scarred, complex mask as she moved amongst the groups of men and women, massive and formidable in her coat of quilted cow-tree bark, planning and talking urgently. It was already late afternoon; that evening Boyd would be leading this ragged army south in another assault on the defense of the Bridge. Allel knew how important this was to her mother; eventually they had to secure a crossing over the river Atad and gain access to the south—otherwise the northern glaciers would surely crush their tiny village before many more winters. Boyd's fists were clenched white as she argued. Allel knew she was brooding over the prospect of another bloody failure, and decided to keep out of her way. She found her grandfather, Lantil, ferrying bowls of excrement and other waste from the bark teepees to the clusters of cow-trees at the heart of the village. Lantil dumped out the bowls into the trees' root systems and tiredly tolerated his granddaughter's chatter. She told him how she'd gone out of the village alone and scrambled over the rocky shoulders of Hafen's Hill, a mile or so away. At the summit she'd thrown herself flat, panting, and stared up in wonder: in the afternoon light the Shell was a glowing quilt, and she'd soon forgotten the wind from the northern ice fields that probed at the crude seams of her shirt... Allel's was a world without a sky. Instead the Shell swept from horizon to horizon, covering the land like a glowing lid of blue, green and startling orange. She'd traced the familiar lines of the ocean boundaries and watched clouds wind themselves into an upside-down storm directly above her. She reached up a finger as if to stir the storm on that great plate hanging over her— —and the bird had tumbled out of the air. She'd scuttled to her knees and cupped the bird in her hands; its heart rattled as ice droplets melted from its wings. The bird was an ice blue, a spectacular color she'd never seen before. And in its beak was a vivid orange flower. The precise color of those strange orange splashes on the Shell. The bird recovered and clattered away, but that didn't matter. Allel knew it must have lost its way and crossed the Gap between the worlds. She'd run off down the heathered slopes to her home. She dogged Lantil's footsteps as he trudged wearily among the teepees. "But if the world and the Shell are globes, what holds them apart?" Perhaps there were great pillars beyond the horizon... Lantil pushed a lank of dirty hair back from his brow. "What does it matter?" "I want to know," she stamped. Her grandfather sighed. "All right." He knelt beside Allel and made a gnarled fist. "There's the world, Home, round like a ball." He cupped his other hand around the fist. "And there's the Shell, a hollow sphere around Home." Now he broke the fist and twirled a fingertip in a helix inside the cupped hand. "The Sun moves through the Gap, giving us day and night, summer and winter." Allel nodded impatiently. "I know all that. But who built it all?" "People, of course." He straightened up, massaging his back. "To keep out monsters called the Xeelee." Allel, wide-eyed, imagined giants stalking beyond the Shell, beating their fists against ocean bottoms and tree roots. "Now I've got to get on," Lantil snapped. "Get on with you, child. Get on..." Grumbling, he went back to his chores. Allel ran off, savoring her newest fragment of knowledge. She imagined flying up to a saucer-shaped land where a world hung in the sky, a ball plastered with rocks and trees. The next morning she rose at dawn. She pushed her way out of the teepee's bark flap, letting the gray cold scour out her night fug. She shivered her way to a cow-tree and sucked icy milk from one of its nipples. The village was hushed in the continued absence of the warriors. A group of old folk and children were at work already, making the most of the precious summer day; they were peeling a fresh sheet of clothlike bark, barely formed, from one of the cow trees. Allel peered furtively up at the Shell. The morning terminator was a gray bar that straddled the horizons, scouring eastward. The night lands beyond were broken by flickering sparks: fires that showed that people lived on the Shell, like flies on that great ceiling. She'd brought a small bark satchel from the teepee; now she arranged it over her shoulder and scurried over the rough track to Hafen's Hill. From the summit she could see the Atad river, a glistening track to the south; the Bridge looked like an indestructible toy, one of the few of the old structures not yet swallowed by the ice. Smoke blurred the scene. She wondered if that was a good sign. She soon forgot the distant battle as she got to work. She opened her satchel and drew out a small lamp, a gourd filled with alcohol fermented from cow-tree fruit. She cut a length of wick with the big stone knife her grandfather had made for her. She held a flint to the wick; it curled and popped as black smoke seeped into the crisp air. Now she opened out a small bag, a rough globe. She held its narrow neck over the flame, and soon her fingers were coated with lamp-black— —and the simple balloon filled up and lurched a few feet into the air. Then it turned belly-up and flopped to the ground. Allel bared her teeth at the Shell as if she owned it already; her heart beat as had that lost bird's. Now then, a little more weight around the mouth... A sandal stamped down, crushing the balloon. The bark of the sandal was crusted with blood and dust. "Get up." Boyd spat the words; blood leaked from a new wound over her eyes. Allel stood, furious. Her anger collided with her mother's contempt. Save for the scars of battle, the years had been easy on Boyd. Mother and daughter faced each other like twins, images in a dark mirror. "Our attack on the Bridge failed," Boyd ground out. "Those bastards holding it want to keep the whole bloody south to themselves. Good people died. And you—you won't even help the old folk with their chores. What do you think you're doing?" Allel picked up the sputtering lamp. "I doubt if you'd understand," she said haughtily. Boyd slapped the lamp from her hands. It smashed against a rock; alcohol pooled and puffed into flame. "You waste your time on rubbish. Don't dare to speak to me like that." Allel bit back her rage. "I fill the bag with smoke. It flies. Build one big enough and I could fly with it—" "More rubbish." Boyd hawked and spat out a ball of bloodstained phlegm; it sizzled in the alcohol fire. "If it's ever left up to you, we'll all die of rubbish." She grabbed a handful of Allel's tunic; her breath was sour. "Or I'll kill you first. And that's not rubbish." She strode off down the Hill's broken flank. "Come on. You'll be grown soon. It's time I put a stop to your questions." Allel didn't move. "Where are we going?" "North. To the place where our people once lived, before the cold drove them out. North to the City." "Why should I come?" Without looking back, Boyd said simply: "Because if you don't I'll break your rubbish neck." Allel looked back ruefully at her home, where the fires of the recent night were still burning. Then she clutched her crumpled shirt closed against the wind and followed her mother. The breeze lifted the abandoned balloon; its final flight ended in the ruins of the lamp, where it began to burn fitfully. The Sun wove its helical web around the world. When night fell Boyd and Allel sheltered beneath a wild cow-tree. In silence, they drank from its milk nipples and broiled slices of meat fruit over a small fire. Boyd slept sternly beneath her quilted coat. Allel shivered in her thin garments, and burrowed into a nest of leaves. She peered up sourly at the Shell's seamless dark, picking out clustered fires. In the morning she stuffed leaves inside her clothes and fashioned herself a rough cap of cow-tree bark. After some days of this the frost grew more persistent, until their feet crunched over thin ice. Light snow fell. They passed a few abandoned settlements; even the hardy cow-trees grew sparse here. A blizzard closed around them like a white mouth. They staggered up to the milkless corpse of a cow-tree. Allel stared at the shrunken nipples and withered fruit. Boyd laughed at her, her eyelids sprinkled with snowflakes. "Comes as a shock, doesn't it? A dead cow-tree. We were given a world filled with beautiful buildings, and cow-trees to feed and clothe us like mothers. A home safe from the Xeelee. "But the world's old and falling apart. The Sun seems to be failing. Ice has covered the cities and frozen the milk in the cow-trees. We trudge through the snow." She began digging into the snow packed against the dry wood. "Come on. We'll let this lot blow itself out. The snow will keep you warm." As she worked, Allel considered a changeless life of endless summer. What would there be to do all day? Her bare fingers grew numb. When the storm blew over they continued the journey. With the Shell like a map over them it was impossible to get lost, and at last they came to the lip of a great natural bowl. Snow pooled around the low buildings of the City, which were sprinkled in two matching crescents. Allel, used to crude teepees of cow-tree bark, touched walls that were as smooth as skin. But the interiors were cold and jumbled, and snow drifted waist-deep in the avenues. Lifting heavy legs out of the snow, they forced their way to the common center of the City's twin crescents. Here was a small cylindrical building, no more than three paces across. Allel helped her mother scrape snow from the door. Boyd blew on damp fingers. "Go ahead," she said slyly. "You first." Allel pushed through the light door— —and stared in astonishment at the far wall of the chamber, at least a hundred paces away. She stumbled backwards and landed in the snow, which soaked into her thin trousers. Boyd laughed, not unkindly, and hauled her to her feet. "A vast hall crumpled into a tiny hut. The people who built this had powers even you never imagined, eh?" Allel stumbled around the tiny building. Where was all that space stored? If not sideways—or behind—or up, or down—what fourth direction was there? The puzzle settled behind her eyes like a spider. The floor area was empty, but the paper-thin walls were covered with pictures, still lit and animated after uncounted generations. "The pictures tell our story," Boyd said gruffly. "How we rose and fell." She stamped snow from her sandals and led the way around the walls. Afterwards Allel thought they could have walked in the opposite direction and lost little of the sense, for the story of humankind had a symmetrical design. The bright side of the symmetry was expansion. From a world without a Shell, tiny ships like streamlined fish swam out on hyperdrive to the stars... "What was 'hyperdrive'? And 'stars'?" They were just words, Boyd said, passed on by other mothers on other days. Allel wondered if her balloon had risen on hyperdrive. She looked closely at the ships but could see no sign of burners. She tried to touch the picture— —and her hand passed into the depthless wall, in a direction she could not identify. She fingered a model ship; it was like a nut drawn on an invisible string. More mysteries... At its peak humanity was a master of many stars—which were evidently places very far away. And then— "And then we met the Xeelee," said Boyd, and they inspected a harrowing battle scene. Elusive fingers snatched at the little ships. "Whoever they were, they were too big for us." After the Xeelee wars came the dark obverse of humanity's conquest of the stars: its sad subsidence back to its home world, prodded by the dark fingers of the Xeelee. They came to the last two panels. Boyd said: "Finally we returned to our home and rebuilt it as a place safe from the Xeelee." The first panel showed a sphere, blue capped with fat brown poles. Painted onto the central cerulean band were clouds and a tiny Sun that twinkled along the equator. The fringes of the polar caps held a lot of detail: sideways-on pictures of trees and men, oriented as if the clouds were "up" and the poles were "down." "I don't understand this one," Boyd admitted. "Maybe it was a stage in the Shell's construction. But here's the world as it is now." The last image was crudely sketched on the surface of the wall, with no depth or animation. It showed a globe with a Shell around it. Allel picked at flaking paint. Boyd coughed self-consciously. "So, you understand now why I brought you here?" Allel inspected paint dust. "This is just dyed cow-tree milk. This last picture must have been added much later—" Boyd swore. She spat on the smooth floor and stalked out. ...And, thought Allel, excited, in that case maybe the world was more like the other image, the blue sphere. But what did it mean? Everyone knew there was a Shell around the world—you could see it... She became aware of her mother's absence. Cursing, she hurried out. Boyd stood a few paces from the door, fists clenched. Feathers of snow drifted around her legs. "I repeat. Why do you think I brought you here?" Allel tried to concentrate on the question. "To show me this place? To tell me its story?" "Yes!" The trackless snow softened Boyd's shout. "Once we rebuilt the whole world, but now we can't even melt a few glaciers." She gripped her daughter's shoulders, not roughly. "People got soft and forgot. Allel—if I fail, you've got to carry on. Perhaps it will fall to you to take over, and lead our people to the Bridge. That's the truth of our world, the only truth. The only way to save ourselves that's within our power." Allel returned her mother's fierce stare. "I understand, but..." Boyd sneered: "But you want to ask the Shell dwellers what it's like living in a saucer." Her eyes were flat, impervious to the hard cold. Allel wondered how she and her mother had grown so far apart, becoming as symmetrical as opposing poles. The one pragmatic, the other—a visionary?—or a fool? Who was right? Perhaps that was a question without an answer— She knew Boyd was trying to force her to grow up. But the Shell arced over them like a roof coated with its own ice. Could she give up all her dreams and become a creature of her mother? "Listen," she said desperately. "I've thought of a way we can take the Bridge." Her mother whirled and drove her palm against Allel's cheek. Blood pumped into Allel's mouth and strange scents flooded her head. "You've learned nothing," Boyd said hoarsely. "I'd rather leave you here." She forced herself forward, fists clenched white. Allel mumbled: "I mean it." She felt blood freezing on her lip. She became aware she'd lost her cap. But Boyd was hesitating. "How?" "If I succeed..." She coughed and spat blood. It was vivid against the snow. "If I succeed, will you help me build a hyperdrive machine to fly to the Shell?" Boyd's eyes narrowed. "I don't believe it. You're bargaining with me..." Then she dug a bark handkerchief out of a voluminous pocket. "Here. Clean yourself up." The dozen warriors converged on the Bridge. They wielded branches hacked from cow-trees, their miraculous meat buds smashed away. To Allel, watching from above, the crude clubs were symbols of the depressing symmetry of humanity's rise and fall. The Bridge was a gleaming parabola plastered with teepees. From the teepees defending warriors emerged, grubby and yelling, brandishing rocks and clubs. Blood splashed over the seamless carriageway. But soon it was hard to separate the two sides, but Allel could see that as before the attackers were being driven away. The breeze picked up and the great balloon over her creaked into motion, its stitched bark straining. The canvas sling chafed her armpits, and she tended the alcohol burners clustered like berries just above her head. The balloon wallowed in the air. Soon its load would be lighter, she thought, uncertain of her feelings. Her shadow drifted over the melee, touching fighters, men and women alike, who wriggled together like blood-soaked termites. They looked up in fear or anticipation. She took a small alcohol lamp, one of a cluster tied to her belt. She lit the lamp, cut its cord with her stone knife, and dropped the lamp delicately into the defenders' muddled line. The lamp flared into flame; a toy man ran screaming, his shirt a torch. Another lamp, and another. Cries of anger sailed up at her, followed by whirling clubs. No weapons could reach her, and she dropped her lamps. Then the defenders' line broke and the battle surged across the Bridge. Teepees crumpled, and old folk screamed. Allel thought she heard her mother shout in triumph. Her lamps gone, Allel dropped the pouch and the balloon rose further. She stared up at the Shell's complex tapestry and waited for a breeze to take her home. She found the teepee's air filled with her mother's sweat and dirt. Boyd's left wrist was a stump of torn blood vessels and shattered bone. It had been cauterized; now Lantil bathed it with milk and tears. Boyd took Allel's forearm in a grip that pulsed with pain. "Daughter! Your damn bag of smoke worked..." Allel tugged gently, wanting only to be released. "Yes. And now you'll have to help me build a real machine to cross the Gap." Lantil pushed at Allel's chest, his liver-spotted hand fluttering like a bird. "You should be ashamed to speak to her that way. Can't you see she's hurt?" But Allel kept her gaze locked with her mother's. Slowly Boyd grinned. "Won't give up, will you? Determined to prove me wrong. All right. On one condition." "What?" "Take me, too. I've done my job here; maybe I want to see the Shell people, too... ah..." The pain silenced her. Lantil pulled his daughter's blood-spattered head against his chest. Allel loosened her mother's grasp, and went to her pallet to start her plans. She lay with her face to the bark wall. The whole village turned out for the launch. They nudged each other and pointed out panels on the balloon which they themselves had helped stitch, forgetting Boyd's five years of bullying. Impeded by their harnesses, Boyd and Allel labored at the bellows-like fuel pumps. The great bark envelope filled slowly, throwing swollen shadows in the flat morning light. Allel eyed the low Sun warily. They'd timed their flight to avoid a collision—fantastic though such a prospect seemed. But, she had reasoned doggedly, the Shell was behind the Sun. They were going to fly to the Shell. Therefore they could hit the Sun, and had to navigate to avoid it. Her harness twitched twice, as if coming awake—and then, with a surprising surge, lifted her. The ground tilted away. People gave a ragged cheer and children chased the balloon's shadow. Boyd roared and waved her good hand at them. Her crippled arm was lashed to the rigging. "We're off, daughter!" she bellowed. The landscape opened out and swallowed up the huddled villagers. To the north the Atad river curved into view, and beyond the site of their old home Allel could see the glaciers prowling the horizon. She felt she was floating into a great silent box. The balloon's throat occluded the Shell's upside-down clouds. She hoisted herself into the rigging to tend the burners, prizing the stubby wicks from the resin-soaked barrels of alcohol. Gritty sweat soaked her eyes. She'd insisted they both wear quilted coats despite Boyd's protests; she remembered the frozen ice-blue bird she'd found on Hafen's Hill on another summer day, five years ago. And sure enough, not many minutes later the dampness at her neck chilled and dried. Her breath caught and soon grew labored. "Even the damn air has a Gap here," growled Boyd. "But you know, this harness isn't chafing so much as it did." Allel, too, felt oddly light; she had a sensation of falling. But they rose smoothly into blue silence. Soon they were miles up; clouds dissolved as they passed into them. Their world collapsed to a Shell-like map, shutting them out; above and below became symmetrical and Allel's stomach lurched. Their rate of ascent slowed. The breeze in the rigging grew softer. The craft lumbered, unstable. "What now?" demanded Boyd uneasily. "Watch the burners." "Yes. I wonder if—ah. The burners! Quick!" The balloon was collapsing. They worked grimly, dragging themselves into the rigging and cutting away the burning wicks. The envelope crumpled over the doused lamps. And Boyd was upside down. Or Allel was. Her harness was slack. The components of their balloon drifted in a jumble. Boyd thrashed in the air as if drowning—but there was no up to kick towards. Fear showed beneath her pale scars. But Allel understood. "It's the middle of the Gap!" Allel yelled, exhilarated by her mother's discomfiture. "The Shell dwellers live upside down. Up for us is down for them. Did we think we'd fly up and bump against the Shell like a ceiling? This is the place where up and down cross over!" Warm air spilled from the balloon and brushed her face. Ground and Shell were enormous parallel plates that careened identically around her. She laughed and swooped. But their equilibrium in the weightless zone was unstable, and soon invisible fingers clutched at them. Wind whistled in the tangled rigging and their harness grew taut again. "We're falling back!" Allel cried in disappointment. Boyd struggled to keep her good arm free. Now air resistance roughly righted them. The balloon opened out like a parachute but scarcely slowed their fall. Boyd roared above the wind: "We've got to light the burners!" They hunted for flints and cupped their hands around the wicks to keep out the snatching breeze. Heat roared up. Boyd thrust at the fuel pumps while Allel scrambled precariously into the tangled rigging to drag at the neck of the envelope, trying to trap all the warmed air. Their descent slowed a little. Allel's arms ached and her hair whipped at her forehead. The ground exploded into unwelcome details, rivers and hills and trees and pebbles— She rolled on impossibly hard earth, grass blades clutching at her face. Her blood was loud in her ears. The balloon folded as if wounded. In a sunlit meadow, mother and daughter lay amid the ruins of their bark spaceship. Sunlight scoured her eyes. Allel sat up, blinking, pushing at the knotted remains of her harness. She was surrounded by cool grass and flowers; a brook led to a stand of cow-trees and the horizon was made up of heather-coated hills. And, as it had always done, the Shell curved over it all like a great blue tent. Boyd slept peacefully in a tatter of the balloon. Allel hesitated for some minutes, vaguely fearful of her mother's reaction. Then she found a remnant of a shattered burner and woke her mother with a cup of brook water. Boyd sat up clumsily, favoring her bad arm. "We failed," Allel said. "Huh?" Allel pointed at the Shell above them. "Look. We must have fallen back. If we'd reached the Shell we'd see the world up there, a ball of rock, cupped by the Shell. And the land would tilt up at the horizon..." Boyd grunted. Sensitive to her daughter's mood, she drank in silence. She probed at her limbs. "At least we're still whole," she rumbled. She looked about. Then—unexpectedly—she grinned. "So we failed, did we? Eh?" She dug her good hand into the ground, and then shook it in Allel's face. "Look at that! Look!" At the heart of the clump was a bright orange flower. A Shell flower. Allel's thoughts swam like fish. "Now I really don't understand..." "We made it. We're on the Shell! That's enough for me." Then Boyd followed her daughter's gaze upwards, to the roof over the world. Her eyes narrowed. Allel said slowly, "Above us we see Home, not the Shell. Yet it looks as the Shell does. The two worlds are complete in themselves, yet they are—wrapped around each other. Symmetry. You see the same thing—a Shell—from whichever world you're on." Boyd nodded shrewdly. "Well, that much I understand. Like us, eh? Two halves of the same whole. No weak center, no protecting Shell. Just the two of us." Allel dropped her eyes, hotly embarrassed. She went on doggedly: "But how? If we're on the Shell, why doesn't the land curve up like a saucer? Why don't we see Home floating up there like a ball? How can it look like another Shell?" Boyd made a little growling noise, and flung the shard of burner into the grass. A small flock of ice-blue birds clattered off, alarmed. "Well, you're the dreamer. Dream up an answer." Allel lay flat. She rested her head on very ordinary loam and stared up through two layers of clouds. She thought of two worlds, each a ball yet each cupping the other like a shell round a nut. How could that be? Her vision of her universe was crumbling, like the flaking planet-in-a-box milk painting on that museum wall. She imagined reaching into the box to the truth— Boyd said gruffly: "Well, what now?" Allel gestured vaguely. "Fix the balloon and get home. We've got to make people understand. Build more balloons and go to the old Cities. Find a way to turn back the glaciers, or fix the Sun..." Boyd was staring past her shoulder. Allel turned—then sat up quickly. The boy stood at the edge of the stand of cow-trees. He was no better dressed than they were; teeth flashed in a dark face as he jabbered at them, smiling and pointing and cupping his hands. Allel watched, baffled. "What's he saying?" Boyd bellowed with laughter. "I think he's asking what it's like living in a saucer." Boyd stood up and, with some dignity, straightened the shreds of her quilted jacket. Allel got to her feet, stiffly. "Come on," said Boyd. "Let's see if his people can cook as well as your grandfather." They walked towards the boy across the meadow of bright orange flowers. "Lethe. I can't believe they fell so far. They've become utterly dependent on that artificial biosphere. They're reduced to technologies of stone and wood—" "But they survived," Eve said. "Humans survived, even beyond the evacuation of the Xeelee. In a world that cared for them. You could argue this is a Utopian vision..." "This world of theirs, with the Shell, is a four-dimensional sphere. No wonder they couldn't figure it out." I thought of three-dimensional analogies. Allel's people were like two-dimensional creatures, constrained to crawl over the surface of a three-dimensional globe. Home and Shell, the twin worlds, were like lines of latitude, above and below—each unbroken, each apparently cupping the other. Just as the diagrams in the "City" had tried to show them. "But they were capable of understanding," Eve said. "After a million years, humans had adapted in subtle ways. Allel had the capacity to visualize, to think in higher dimensions. She could have understood, if someone had explained it to her. As those diagrams in the place she called the City were meant to. And in time, she would figure out some of it..." "They were trapped," I said. "In a prison of folded space-time." "Perhaps," said Eve. "Perhaps. But they didn't give up..."