by Ian Stewart
Early, small preadolescents, third-instar metamorphs, generated copious quantities of liftgas and rose in a mere forty days from the crushing pressures of the abyssal oceans to the thin air of the troposphere, hugging the upper levels of Secondhome's cloud layer but remaining above them. By the time they got there, their lift-sacs had metamorphosed into regular hydrogen-filled gas-sacs. Up in the weak daylight, the preadolescent colony creatures could begin to extract energy from the sun, grow, and change. Borne this way and that on the alternating jets that separated the atmospheric bands, now soaring, now plunging on convection currents and storm surges, assailed by turbulent swirls, they were relatively safe from predation—for although they would have provided a rich source of protein for any hungry predator, the troposphere was suitable only for a semi-vegetative existence. Nevertheless, the occasional raid by a desperate snark pack, gasping for breath in the thin air, disturbed their otherwise tranquil existence. And many accidents could happen during the lengthy childhood of a preadolescent.
The audience (eager, attentive) could see it now, an increasingly panic-stricken adolescent dropping toward the city, desperate in its search for protection from the predators cruising hungrily below. Instinct, honed by evolution, drew the pathetic creature toward the comforting bulk of the city, and wafted pheromones from the congregation of sexually excited adults attracted it to the birthing arena and the trimming pond. A squadron of midwives rose to meet it, in a glorious display of massed aerobatics, guiding the youngster down to the waiting sculptor-surgeons, calming it with soothing grunts and chanted birth-poems. Already they were assessing its hugely redundant mass of gas-sac-riddled tissues in the hope of determining the True Adult that according to mythology and custom was supposed to be buried within.
The adolescent was chivied into position, tied down with thick fleshy ropes, and half submerged in the anesthetic balm of the trimming pond. The sculptor-surgeons readied their trimming knives—sharp blades of symbiautic metal mounted on long, slender poles, some joined in pairs to pivot like scissors, others bearing ugly, serrated edges.
The midwives splashed liquid from the pond onto the adolescent's quivering exterior, to ensure that there would be as little pain as possible. Balladeer winced as a sympathetic ache shot through his trunk tips.
Satisfied, the midwives drew back . . . and the surgeons advanced. Symbiaut assistants sampled genetic imprints from the outermost sacs, comparing them to the city's records, seeking profiles that were most needed or that hinted at unusual gifts. Unwanted sacs were sculpted away by the skilled surgeons, who took care to maintain the structural integrity of the sacs that remained. The carving of a True Adult was a matter for experience and compromise: the adolescent must be left with a sustainable harvest of sacs, as well as an approved genetic makeup and a functional procerebral organ. More than one promising citizen had been ruined because the sculptor-surgeons had placed too much value on genetically pleasing combinations, choosing sacs that lacked adequate physiological cohesion. Most juveniles would be edited clean away in the search for acceptable combinations, a strategy that helped keep the population of near-immortals within bounds.
Balladeer felt his body trembling with emotion as the trimming pool became discolored by seeping body fluids. Discarded gas-sacs were towed away by the midwives, and teams of symbiauts distributed small morsels of afterbirth to the audience, who ate them. Balladeer's hide rippled with joy as he gulped down a dripping gobbet of flesh. As the adolescent's unwanted fluids dribbled down their hides and ran back down the conical sides of the amphitheater to pool at the edges of the birthing arena, the audience convulsed in a collective orgy of sexual secretion. A blizzard of nanogametes filled the amphitheater, so dense that for a time it all but obscured the view. It was a scene of extreme beauty and emotional significance, and it left the audience sated and drained of energy, trembling as they rode the bars of the tethering ring and surged from side to side in great moaning waves of crowd-sway. Balladeer found it hard not to swoon into first-stage estivation, and he was by no means alone.
As the blizzard began to clear, the dozy postclimactic audience could see the outline of a recognizable adolescent emerging from the carnage, drenched in anesthetic liquid and its own body fluids, dripping thick yellow gore.
The surgeon-in-chief sliced away a few remaining strands of unwanted flesh, ate them, discussed the genetic and physiological indicators with its retinue of symbiauts, and pronounced the infant blimp to be both viable and socially desirable. Two vital questions now had to be answered. Was the infant sane? Was it competent at offcasting? To find out, the midwives bore the infant away to a specially prepared blisterpond. Now the healing would begin, and the Fourth Change . . . and the Life Trials.
In its specially cultivated nursery blisterpond, the juvenile blimp's consciousness seeped into being. At first it could sense nothing except an all-embracing dampness. As the days passed, other sensations began to impress themselves upon the rapidly developing young mind, pruning the overcrowded network of neural pathways to those that gave the mind its texture of awareness and its computational/processing abilities . . . The juvenile's sense of touch became many times more sensitive as pathways began to specialize for temperature, roughness, stickiness, gel-idity, and the detection of edges, corners, sharp spikes . . . textural boundaries and orientation gradients . . . gradually a new world of feel took coherent spatial order ("shape" is the wrong word).
The juvenile's sense of molecular vibrations also began to tailor itself to key features of important compounds—both micromolecules and macromolecules, for this was an adaptive learning process and it could learn complex patterns as readily as simple ones. Indeed, to the incipient neural network there was no distinction ... for all were just input/ouput reinforcement associations. The watching psychodacts made sure that the infant was subjected to a steady stream of culturally significant molecules, from liftgas in trace amounts to social pheromone suites that were likely to be encountered during focal occasions—group nanogametogenesis, conclave bureaubonding, and the nine levels of estivation.
Only now did the psychodacts begin to initialize the infant's longer-range senses. First hearing, as nerve-laden membranes dried out and began to detect the airborne vibrations that filtered through the blisterpond's insulating rind . . . Then vision, as the photochemistry of the blisterpond's interior was altered by the psychodacts so that the damp surfaces began to glow in all the colors of the mistbow The lenses of blimp eyes were made from a rare substance: water ice. They were therefore receptive only to wavelengths to which water was transparent.
There was one further sense to be initialized, but not yet. First, the juvenile had to prove itself fit for adulthood. It had to offcast.
The juvenile's newly established sense of molecular "taste" informed it that the mix of liquids seeping through the blisterpond's membranous walls had suddenly changed, becoming far richer in metallic salts. Now its metabolism had to kick into a new gear to deal with compounds that were essential for life, yet, if they overaccumulated in normal bodily tissues, were fatal poisons.
Possibly . . . Yes! This juvenile was functional! Its tissues had created a sealed cavity near a weak section of hide! Within, electrolytic reactions were bleeding off liftgas and sequestering metal atoms into a burgeoning crystalline matrix. The atoms were segregated according to atomic number, and unwanted elements were excreted as small flakes. In the normal world of the city, roving cyclers would collect any flakes that they encountered, store them if they had any intrinsic value, and unceremoniously dump them over the side if not. As unwanted flakes fluttered down into the darkness, acids and alkalis would convert them back into salts, to be selectively ingested by aeroplankton and cyclozygotes ... or to fall for hundreds of thousands of years, all the way to the core.
The psychodacts rejoiced as the juvenile's metabolism laid down its metal atoms layer by later, creating macroscopic monocrystalline forms that meshed with hair-thin tolerances to form a complex t
hree-dimensional structure. When that first reflex-engineered symbiaut was complete, the thin skin of the juvenile's body cavity split, peeled back ... A muscular spasm ejected the symbiotic mechano-chemical construct/growth, and it tumbled to the bed of the blisterpond. Worryingly it was a poor construct, and at first they doubted it could be functional; but perhaps it would suffice after all . . . Lying in warm damp slush, it began to absorb electromagnetic energy from the photoactive walls.
When its stored energy was adequate, the symbiaut self-activated. Awkwardly and with much grinding of gears, it struggled over to a sensitized area of the blisterpond's wall and began to burrow a ragged tunnel through the rind.
Outside, a small crowd of blimps had gathered, the juvenile's prospective squod, or socioeconomic bonding group. They listened in to the young mind's strong but uncontrolled squark emissions, tapping directly into its untrained sensorium, their excitement growing as the new citizen successfully surmounted each of the fifty-five traditional stages of awareness and the thirty-four cusps of sentience.
A small region of the blisterpond's rind crumbled, and the newly offcast construct emerged into the pale light of the Secondhome day . . . and seized up.
Baby's first symbiaut.
There would be many more offcast mechanisms, and better ones—constructed to different "designs" determined by culturo-chemical feedback mediated by pheromone profiles. If a blimp did not excrete its ingested metals, it would die, so the ability to excrete had evolved along with the earliest proto-blimps. Subsequent evolution had refined the excretion process from simple expulsion to the tumorlike growth of rudimentary tools—needles, blades, pounders—and thence, with increasing rapidity as the production process became increasingly sophisticated and eventually self-referential, into a versatile range of symbiotic machines without which blimp culture could no longer function.
These were the symbiauts and their many variants. They had no genetics, since the blimps' genes, physiology, and culture ensured that the symbiaut adhered to mechanically viable "designs." Yet there had never been any designer. Were symbiauts a form of life, or not? It was pointless to debate, and the blimps had never given the question serious consideration. Symbiautic constructs were what they were: complex organizations of metallic matter that were adaptable, autonomous, and without doubt as conscious as the blimps themselves.
The blimps knew that symbiaut minds were the equal of their own because they could bureaubond with them by squark telepathy. A symbiaut's senses were different from those of a blimp— sharper and more "digital," discrete rather than continuous, combinatorial rather than topological/analytic. Philosophers from both macrotaxa—organic and symbiometallic—speculated that subtle overtones were lost in the "translation" from organic minds to selectronic ones. Many blimps were convinced, for example, that no symbiaut could truly appreciate the exquisite anguish of a deathsong. Symbiauts knew that the blimp mind was insensitive to the beauty of well-crafted algorithmic topography.
The symbiaut's tunneling allowed the outside air to flow into the blisterpond. This sudden influx had two effects. The blis-terpond opened like a flower, its rind splitting into half a dozen segments that peeled back in tightening coils. And the juveniles mind became aware of incoming squark wavepackets, as well as broadcast them wholesale. In a single timeless instant, the adolescent blimp imprinted on its squod-elect. Adult patterns of thinking downloaded into its receptive memory. Unlike the symbiauts, whose symbi-engineered digital mind could hard-download operational code, this was a soft download of approximate patterns, nuances of neural flow, fuzzy-edged templates that would have to be sharpened by subsequent experience. Yet, in that instant, the adolescent grew up. It ceased to be an animal and became a citizen.
The squod's group mind bonded, merged, and became one.
Tentatively, the group mind explored itself, accommodating the new member—its first for a quarter of a million years.
When the mind later separated, the juvenile/citizen would carry with it vague memories from long before its birth, soft-downloaded from others in its squod. Most importantly, it would register its own sense of identity, an indelible shared memory of its own Commencement—its emergence from the blisterpond as a true citizen with its symbiaut construct as proof. As its body metamorphosed into adult form, its mind would forever retain these powerful memories and be shaped by them.
The squod explored the newcomer and hoped that she would be an adequate replacement for Pungent Whimsy. Whimsy, sorely missed by them all, had been detonated by a freak stroke of lightning while illicitly observing the Forbidden Storms during a risky circumnavigation of the Whirl. This dangerous diversion had been occasioned by an unusually severe vortex season in the south fringe of the Equatorial Belt, but in retrospect the city had made a bad choice.
The squod explored, contemplated, and considered itself moderately satisfied. Encouragingly, the newborn had a huge potential for unorthodoxy ... a vice that this particular squod secretly rehshed, for they were subversives, every one.
They cemented her membership with a Ceremony of Nomination, dubbing her Bright Halfholder in recognition of her shining clarity of thought and her semi-competent grasp of offcasting.
Her squod was Violent Foam.
The city's thoroughfares were even more crowded than usual, yet most of the malls were deserted. There was an air of expectancy, especially among the younger blimps, and even Halfholder—whose ability to intuit mass consensus was still at a formative stage—was aware that something special must be happening.
She stopped to look at the crowds bubbling up from the lower levels, but the rest of her squod were in a hurry. They didn't want to miss the fun.
«Where are wehhh!hqqq!cpcp!cp+++» — she was still learning to direct her thoughts, too, and for a moment they tailed off into overspill from the nonlinguistic parts of her brain— «going?»
«We are going to see the fireworks display, Halfholder.»
Having access to a group mind is not the same as understanding it: juvenile blimps still had to learn to put the group knowledge into context. «What is a fireworks display?»
«It is a surprise. You will enjoy it. Fireworks are a lot of fun. But you must hurry, or all the best tethering rods will be taken, and then you will not get such a good view.»
That sounded promising, and Halfholder concentrated on staying with the rest of the squod. She had never seen so many blimps all going in the same direction, certainly not at night.
They found a good place to tether themselves, and Halfholder made sure she'd gotten a firm grip with several trunks. It would be embarrassing to start floating away in front of so many others.
The banks of tethering rods quickly filled up, and Halfholder was glad she'd hurried.
«What is going to happen?» If she had been more adept at bonding, she wouldn't have needed to ask—she could have called up the information from the memories of any member of the squod—but that was adolescents for you. She was quite advanced in most respects, and it was easy to forget that she was only a few hundred thousand years old.
«You will see. Nothing important will happen until they have dimmed the city lights and given our night-eyes time to adjust, do not worry.»
«Why are there so many blimps?»
«Because they want to see the fireworks, too.»
«Why?»
«Because everybody likes watching fireworks.»
«Why?»
«They just do, Halfholder. Blimps are like that.»
«W—» Maybe not. The squod often got irritated if she asked too many questions in a row.
The lighting began to dim, and the crowd took the hint and began to settle down. Overhead, skeins of lighter cloud ratcheted across the impenetrable darkness of the upper layers. At the city's own level, visibility was fairly clear: the city authorities had authorized a descent to a relatively cloud-free level.
«Look into the sky, Halfholder. No, not straight up, all you will see there is clouds. Look forward,
over the city's prow . . . yes, that is right. And get your chromatic-eyes ready, or you will miss the colors.»
Obediently, the young blimp exposed the color-sensitive elements in her eye-ring. Ahead, the cloud layer began to glow, a warm rich orange. Then a brilliant yellow streak split the sky, slanting across her field of vision and disappearing beneath the bulk of the city The crowd moaned with pleasure as the afterglow faded from violet to pale blue.
«That was a firework, Halfholder. Keep looking, there will be a lot more.»
The city's flight had been diverted months back to bring it close to the fireworks display, as soon as the Elders had passed on the information from the symbiautic watchers. The display would last for at least half an hour.
«What is that?»
«That sound? Almost like somebody wailing? That is the sound from the fireworks. It takes it longer to get here than the light.» This was new information, and Halfholder filed it away for later consideration. She hadn't realized that sound took time to go anywhere. In fact, she hadn't realized that it traveled at all—but of course it must; it was obvious once you thought about it.
Another streak sliced through the darkness, a third, a fourth. Then dozens, almost at the same time. One exploded into a brilliant green fireball right in front of them, followed seconds later by a loud bang. There was a sudden hiss of ejected lift-gas, an instinctive reaction of the crowd. «You are lucky, Halfholder. Those are rare. The last time I saw a banger was three million years ago.»
«Why did it go bang?»
«There must have been a gas bubble trapped inside the firework as it heated up. The bubble burst.»
They watched the pyrotechnic display until all trace of the last firework was gone. Halfholder noticed that afterward the air smelled fresh and clean.
«Yes. You may notice a lot more aeroplankton soon: keep