Noise

I Overture

Poetically and almost literally, Kainui’s mantle is at endless war with its overlying ocean. Perhaps they are simply too intimate; they confront each other directly, with no identifiable intervening crust. The underside of the interface is not quite liquid most of the time; the upper is technically gas, since the ocean at that depth is far above water’s critical temperature.

What pass for tectonic plates, from township to county size, are solid enough to crack and tilt and be carried as individual units by mantle convection. Tsunamis are generated constantly, sometimes by abrupt plate shifts—quakes—sometimes by vulcanism, though there is nothing at all like a Terrestrial volcano on the world.

When magma emerges from the mantle to become lava and meets the sea there is of course violence, but Kainui has never experienced a Krakatoa-type steam blast. The weight of twenty-eight hundred kilometers of water, nearly all of it far saltier than any Earth ocean, provides some eighty thousand atmospheres of pressure. A few hundred kelvins rise in temperature has no real effect on either phase or volume.

So when, one day, a tenth of a cubic kilometer of glowing liquid silicate was suddenly exposed to ocean bottom along the line between two spreading plates, the result was merely a linear-source sound wave.

Its front spread out as wave fronts do, trying to become flatter and flatter as it left its source behind. It failed miserably. It passed through layers of differing salinity, temperature, and tonnage of suspended matter. Sometimes locally it turned concave and was focused so narrowly as almost to regain its original pressure. Sometimes it diverged, but its total energy degraded only gradually toward heat.

Nearly an hour later, when parts of it were nearing the ocean surface, that energy had been distributed over much of the planet, but there were still local, focused, high-pressure regions. Now the background pressure was getting low enough to let the water molecules move noticeably with the front.

When it actually reached the next real interface, between ocean and atmosphere, the water—long since actually liquid—was able to rise, and a tsunami was born. Most of it was imperceptible to human senses, since it covered a large area and had no coast to overwhelm; but even in the last few kilometers there had been some local refraction. In several places smaller microtsunamis originated, and Mike Hoani was very aware of one of these.

Its bulge was three or four hundred meters across and perhaps twenty above the general sea level, but this was not itself an easily spotted reference. The Malolo’s upward acceleration was only barely noticeable to anyone on board, but her tilt was another matter.

Mike had been trying to get his sea legs for two days now, since his first and last real view of a local tsunami. That had been during launch, when either the arm supporting the dock had been swinging downward or Muamoku had been rising. Cities were massive enough to respond rather slowly to changes in ambient pressure. The ship was different.

Ocean swells, on the rare occasions that they were the only disturbances present, Mike could usually handle; if they were too long-waved to see, they were, under Kainui’s one-third Earth gravity, too slow to be a problem. The sometimes strangely shaped and always unpredictable microtsunamis, analogous to the streaks of light focused on the bottom of a washbasin when the water is stirred, were quite another matter; he didn’t merely lose his footing, he was often thrown from it.

The catamaran’s deck was railed in many places and rigged with safety lines in most of the rest, but not continuously or everywhere; the need to dive overboard or climb back was random in both time and place. It was wet, since there was enough wind to break wave tops and provide spray. It was slippery. This time Mike slid.

He was not hurt, being encased in sound armor fifteen centimeters thick except near joints, but he was frightened. Surprising both himself and the witnesses, however, he did the right thing. He swung the helmet hinged between his shoulders forward over his head, latched it, and then grasped at a passing line. He managed to catch this and stop his slide before actually going overboard. The deck was still rocking, and without shame he crawled away from its edge before trying to regain his feet.

Even the child at the masthead was watching him, lookout duty ignored for the moment, and the three native faces showed expressions of approval around their breathing masks. Maybe all four, counting Mike himself, were thinking that this Hoani fellow mightn’t be too much of a burden after all, but nobody said anything. Especially Mike. He just stood up, carefully.

A mere day later, that particular wave had long gone to warm the surface water and the air above it. Mike’s reflexes had improved even in that time, and he had some attention to spare now when the lookout’s shrill voice sounded from above. It was hard to distinguish words over the endless thunder, but he followed them fairly well.

“I’a’uri! One hand, port bow, half a kilo, past ripe!” The captain’s response was a wave, and Keokolo at the tiller simply changed heading. The breathing leaf had not yet been deployed that morning, and steering was straightforward. Mike, guided by the child’s words, made out a dark-colored patch of what might have been seaweed in the indicated direction. It seemed more than a hundred meters across. He assumed it was a sample of the pseudolife they had come to harvest, but it meant nothing specific to him until after Malolo had been brought to at its edge.

Even then he could make out no real details, except that the weed seemed to be growing on something clear suspended a meter or so under the surface.

At that point both adult crew members expressed approval of ’Ao’s judgment. She had descended from the mast without orders and was waiting with just a faint expression of anxiety visible around her mask. The passenger, who had a youngster of his own on Earth, could interpret this; the child had been afraid of being wrong. She relaxed visibly at the captain’s words.

Mike Hoani couldn’t quite decide whether he should be surprised or not. None of the crew had seemed to be, and it was reasonable that the youngster would be the first to spot the i’a’uri, whatever that was, since she spent much of her waking time at the masthead; but like Mike she was on her first sortie. Unlike him, she was barely forty years old and still carried her doll even on duty.

Her ability not only to identify the i’a’uri but to give details seemed to say more about Kainuian education than Mike had guessed so far. Apparently her instructors had more or less outgrown the notion that experience is the best teacher even though she had been sent to sea while still a child.

That was a point to be noted; it might possibly fit in with the convergent-evolution language thesis he was hoping to complete while on the planet. Different floating cities had been built by colonists from different Polynesian islands, but generations of trade among them had gradually caused a blending of tongues that was still far from complete.

Nothing much else had seemed surprising, either, during the time they had now been sailing. The weather had been fine; there had seldom been more than a dozen of the world’s immensely tall thunderheads in view at any one time, though of course the ubiquitous ionized haze hid such things long before one’s line of sight reached the distant horizon. The thermals had not forced Malolo to change her basically northward course; they were routine. Even little ’Ao had needed no verbal orders; she obeyed a simple gesture from the captain whenever the ship had driven into the hail column under one of them, darting over to the collecting sheet and standing by to sweep the hailstones either into the drinking and bathing breakers before they melted and absorbed too much carbon dioxide or, if there was too much of the material, overside.

Only one other vessel had been seen during that time. Wanaka, Malolo’s captain, had logged—and reported to the others with some amusement, as though they couldn’t see for themselves—that it bore the same name as their own craft, but was a single-hulled double-outrigger of about twice their own tonnage flying the flag of Fou Savai’i and, like themselves, the “nothing to trade yet” pennant. Both adults seemed a little surprised that it was sailing at search speed; their own craft at the moment had its kumu’rau deployed, since the suns were high and it was rare for any craft to miss an opportunity to top off on oxygen. This of course could not be done at night, and at least some of each day had to be spent searching for metal.

The name went into Mike’s mental notebook, too. Malolo meant “flying fish” in more than one classical Polynesian language—on a planet that had no native bacteria, much less vertebrates, as far as anyone had been able to find out.

The thing ’Ao had just seen and identified had been visible enough at half a kilometer, of course. The weather was unchanged, with Kaihapa barely visible through the haze, hanging high in the western sky and the suns nearly at the meridian. There was enough wind to move the ship at a reasonable clip, but not enough to break the swells; and by now, with his improving reflexes, the seismic bumps and hollows in the ocean surface were becoming merely a minor background nuisance to the passenger. They caused the top of the mast to swerve and jiggle in a way that made him avoid watching it, but ’Ao typically held on without apparent trouble and with her doll clinging to her shoulder, neither showing any sign of being bothered.

Malolo was now hove to at the edge of twenty thousand or so square meters of rippling jelly floating just under the surface. Wanaka, the vessel’s owner and captain, was still aboard to make sure it stayed there. ’Ao, Mike, and Keokolo had flipped their helmets on and gone overboard to harvest.

The first two were connected by a safety line, since the visitor knew practically nothing of Kainui hand language, and vocal communication would have been hopeless below the surface even if helmets had been unnecessary. Noise from the ocean bottom was continuous, and deafening, and often deadly in overpressure. Mike had been told firmly to stay with the child, as though the connecting rope allowed anything else. He watched her carefully. He already knew why she avoided the nearly black leaves, which spread just at the surface and shadowed more than half the slimy stuff underneath, but he had been told practically nothing about the actual mechanics of harvesting. The items they wanted, he did know, were in the sheet of jelly itself, whose upper surface oscillated vertically under the push of the endless random microtsunamis and more regular swells, varying from half a meter to something like two and a half below that of the even more violently rippling water. Sometimes Mike found himself wading unsteadily on jelly, sometimes swimming. The meter-and-a-quarter-tall child always had to swim.

It seemed simple enough. ’Ao’s thinly gloved hands groped over the jelly and every few moments found a slit not visible to the man. Reaching a few centimeters into this she would feel around briefly and pull the hand back either empty or grasping a black purselike object ten or twelve centimeters long that reminded Mike of a shark’s egg case. This she would deposit in a circular basket being towed behind her, and resume groping. ’Oloa, the doll, clung to her shoulder still, but ’Ao paid no attention to it; she was working.

Keokolo seemed to be doing the same thing, except that the objects he gathered were clear and glassy in appearance, and the container in which he placed them, unlike the girl’s, seemed to need no floats. Periodically one of the harvesters would return to Malolo and hand the collecting basket up to the captain, who transferred its contents quickly to something Mike couldn’t see, since the salt-stained gunwale was more than a meter above him. Wanaka would then return the bucket to the harvester.

It was a long, rather boring, and tiring process. The noise armor was heavy and much less flexible than Mike would have liked, and the harvesters seemed to be taking a completely random course over the i’a’uri’s surface; the visitor could not even guess how nearly finished they might be. They stopped and ate for three-quarters of an hour while Kaihapa eclipsed the suns, then resumed work until the latter set. Mike had tried to calculate how many of the items being collected there might be on the vast surface of the pseudoorganism, and suspected Malolo might be there for several days; but when he suggested this aloud, the captain shook her now-exposed head negatively.

“No,” she said through her breathing mask, rather regretfully he thought. “If we’d come across it sooner we might have been able to get a full load, but as ’Ao said when she spotted it, this one is quite a bit past ripe. Its batteries are nearly full, and there’s no way to keep it from sinking out of reach after the leaves are gone. It’s a rather old design, though a very efficient collector. Its iron is very pure and its water drinkable. It’s too bad to see so much of it get away, though of course having only one cargo item to trade isn’t good policy anyway.”

Mike figuratively kicked himself for not having figured out that the pseudoorganism’s name probably came from a blend of a Samoan word for “fish” and a Tahitian one for “iron,” and added several notes to his mental collection.

“D’you think we should split it, or let it die?” asked Keokolo.

“Oh, split it. It’s still a useful type, and if it ever can’t compete with newer stuff the problem will take care of itself,” answered his wife. “We have about a third of what I want, and should get the rest before sunset tomorrow. When we do, you can show ’Ao and Mike how to divide it without depowering one of the halves.”

“I already know about that!” the child cut in.

“Your badge doesn’t say so, but you can show Keo if you want. We’ll be glad to upgrade you.”

Mike had a pretty good idea of what they were talking about. ’Ao was not the child of the adult crew members, though they were married and had a daughter in Muamoku. No children of the same Kainui family ever sortied on the same vessel with their parents or usually even at the same time, but children started their practical education early. ’Ao was not quite forty, nearly ten in Mike’s years. Family separation was a custom retained from their Terrestrial ancestors, who had placed high importance on the preservation of family lines. ’Ao’s parents and small brother were not afloat just now and none, except the brother, was likely to embark until she herself had either come home or been away long enough to justify assuming that she had been lost at sea or adopted by another city.

Mike said nothing; he listened, fitting what he heard into his increasingly detailed mental picture of the colony world’s society and, most particularly, its pattern of languages. By ancestry he was himself as pure Maori as Earth could now provide. By training he was a historian and philologist, and he had already found in trade-centered Muamoku, the only Kainuian city that hosted space craft, that he could make sense out of the Babel of mixed and evolved Polynesian languages in that one Kainuian settlement more readily than most of its citizens could adapt to that of another. He had met and talked extensively with many visitors and adoptees there, where he had stayed until embarking on Malolo a few days before.

Not all the time after the suns set was spent in talking; food, sleep, and exercise were all essential for the crew as well as their visitor; the three crew members could not all sleep at once; and maintenance of the breathing and food supply apparatus was always needed. Just now Malolo had to be kept close to, or at least in sight of, the i’a’uri. Once lost, this would be nearly impossible to find again—certainly not before it had finished ripening, released its water and iron back to the ocean, and sunk back to the deeps to collect and purify more. There was no telling when another useful pseudoorganism would be encountered, though the chances were reasonably good that it would be within a few days.

“Chance” was unfortunately the key word.

Mike’s mental notes had to be recorded more permanently. The others knew what he was doing, and the adults paid little attention to him beyond the needs of courtesy.

’Ao’s curiosity seemed more genuine. She asked many questions and explained his answers carefully to her doll, who probably didn’t understand but at least remembered. Mike questioned the child in turn, trying to learn how she had recognized the iron-fish through Kainui’s haze. She had some trouble explaining; color was understandable, but she was also trying to describe leaf pattern, which still seemed entirely chaotic to the visitor. They had not, obviously, been close enough at the time of spotting to recognize the detailed shape of the palm-wide two-meter-long ribbons of leaf. Mike still felt sure of that when the child finally sought her hammock, and still very unsure of what had actually guided her.

There were more clouds the next day than before—still all thunderheads—but the wind was lighter. Hoani had made no sense yet out of the planet’s meteorology, and wasn’t sure the colonists had either. A world with no land whatever, unless an occasional floating mass of pseudobiology or slab of coral from a detached city raft or dock counted, might be expected to have a very simple air circulation pattern. Kainui did, as far as climate was concerned, but weather was different. It seemed to be simply chaotic.

The tsunamis were as variable as usual, but even the visitor was getting accustomed to them; he had only fallen twice during the short time he had spent on deck that morning. It was the small ones that were troublesome; the really big humps of water extended beyond the range of vision and could barely be felt either tilting the ship or accelerating her up and down. Even in the low gravity the Earth native was usually quite unconscious of such small changes. It was when the deck really tilted that his troubles came.

When the kumu’rau was deployed he had had to develop a separate set of reflexes, since the scaly-looking strip of tissue, ten meters wide and two hundred long, trailing from Malolo’s stern greatly modified the catamaran’s response to waves in general; that was today’s problem. The “tree-leaf” was deployed when they were not under way by daylight.

On the i’a’uri the swimmers were affected only by the very smallest, most local bumps. These changed the depth of the jelly mass as it humped and hollowed, and meant that a collector floating at a set depth was sometimes within reach of the mass and sometimes not. No one had suggested that Mike should try collecting, and the other two seemed not to be bothered by the irregular motion.

The drinking breakers were now full, so Keo was also collecting iron today. This time they were trusting their guest without a safety line, and ’Ao was working with visibly greater speed. Mike wasn’t sure whether he should feel guilty or not. If Malolo couldn’t get the load Wanaka wanted before their iron mine sank again, perhaps he should; and even he could see the change in the leaves. They were lighter in color and shrinking in length. He had worked out for himself that they must be using radiation from the suns to make something like ATP or azide ion or some other battery molecule, and that the pseudoorganism’s hunger for whatever it was must be almost appeased. He himself must therefore be somewhat at fault for delaying the harvest and decreasing the amount of cargo the crew could collect, though he couldn’t think of any way just then to frame an apology. He wished he could do something helpful himself.

Hours rolled by, however, with pods of iron still coming aboard, and Mike kept feeling better and better until shortly after the suns reached the meridian. Then the captain gestured ’Ao out of the sea as she arrived with a full bucket, and a few minutes later did the same for Keo.

“That had better do,” she said when all helmets had been flipped back. “’Ao, take down the ‘not yet’ pennant. You’ve spotted the nucleus?” Both heads nodded; that bit of body language was standard even on the colony world. “All right. Keo, get the gen kit. ’Ao says she knows mitosis; let her show you. If she messes it up, it won’t be very important with this one, so don’t interrupt her unless things get dangerous. Mike, you may go back with them and watch if you like, but you won’t be able to understand much. They’ll—or she will—be installing a chromosome unit which will make this machine grow a new nucleus and then divide. Just once.”

“They’re not built to reproduce indefinitely?”

“This is a small planet.” Hoani almost pointed out that it had a third more surface than his own, then saw the point the captain probably had in mind. Any planet is small when confronted with the exponential behavior of life. “We can’t afford to let anything reproduce uncontrolled. We could, no doubt, design a set of predators to hold down the metal-fish population, but it seems more comfortable to do our own planning than to depend on that sort of statistic, which never worked very well on Earth. Escaped Terrestrial microlife we worry about, but so far it seems to be balancing itself off. The varieties that can survive in the ocean here have both prey and predator types, and the cycles phase locally. With large pseudolife forms, phases would be worldwide, and the times when the predators reach a high count but haven’t quite run themselves out of food would be very unproductive.”

The visitor nodded. His own world had been painfully slow to learn that lesson, and was still far from being back to its calculated half billion equilibrium human population. His own child had been permitted as a result of an agreement with authorities that either both parents or the child would emigrate when the latter reached self-supporting status.

“You didn’t seem to hesitate when Keo asked you what to do this time,” he remarked, returning to the question of the iron-fish’s disposal.

“I did my hesitating earlier. I’d made up my mind when he asked.”

“So this thing you’re planting won’t reproduce itself; it will just cause the i’a’uri to divide once.”

“Right.”

“Even if ’Ao makes a mistake in the installation?”

“Yes. All she could probably do wrong would either prevent it from dividing at all, or kill it—effectively, the same result. It wouldn’t be a catastrophe. I’d’ve suggested that she try the job even if she hadn’t asked to. I’m glad she did; some youngsters are afraid to try anything they haven’t done before.”

“I’ve known some who went the other way—were too eager to show off and got badly burned mentally and sometimes literally by failure.”

“So have I. We’ll hope Keo’s judgment about helping turns out to be sound. Here they come. Do you want to go with them?”

“Am I likely to do any damage?”

“Not as long as you do nothing but watch. Come to think of it, you could even help. Ask her to explain things to you as she goes along. That should make her stop to think at each step—though I think she would anyway, with Keo looking over her shoulder.”

“But how can she explain to me in the sea? I don’t—”

“You can’t speak Finger, of course. I forgot. Well, it was a good idea while it lasted. Please don’t mention that slip to Keo. Husbands are hard enough to keep properly respectful as it is. But you may as well watch ’Ao anyway, if you wish; I expect you’ll learn something, and you seem to have normal human curiosity.”

Mike nodded and donned his helmet, fastening it under the critical gaze of the captain. The child had already dived overboard; Keo entered the water more carefully, burdened with a rectangular case about forty centimeters in its longest dimension and a little less than half that in the other two. The visitor followed them over the rippling slime, ’Ao leading the way. All were swimming, the yellow tops and white soles of the child’s flipperlike foot armor providing an easy guide for the others.

Mike couldn’t tell how close to the center of the huge pseudoorganism they got, but their course seemed straight; there was no wandering around to find their target. Once within a dozen meters or so, even he was pretty sure he could recognize it.

A bulge of darker-tinted jelly swelled almost to the ocean surface, the area for several meters around entirely devoid of leaves. The guest couldn’t remember having seen the thing before, but realized that it might not have been so distinct during the harvesting. That was something he could ask later, if the development cycle of this particular form of pseudolife ever seemed to be important to anyone but harvesters. He wouldn’t be expected to know about that in advance.

Keokolo and the girl squeezed air from their buoyancy controls and settled to the bulge. Mike remained drifting above them. Keo handed over the case he had been carrying, and ’Ao unlatched and swung back one of its narrower sides. No bubbles rose; it had apparently contained water all along—water of about the same density as that around them. This was probably, Mike realized, about the same as the general upper ocean value at this distance from the equatorial endless rain belt, since there had been no major storms in the last couple of days. Rain and hail could dilute the surface layers almost to fresh water density, at least by percentage salinity and osmotic factors, but more than an hour or so after an ordinary storm even surface water was likely to have too high a concentration of nasty ions like nickel or cadmium to be safely drinkable.

Mike suddenly could guess why Wanaka had decided Malolo was loaded enough for now, high as she was still riding.

With obvious care, ’Ao was taking something from the case. It was rather fish-shaped, though circular in cross section and lacking fins or tail. At first its skin was smooth; then, as the child ran gloved fingers along a set of reddish stripes—a dozen or more, though Mike couldn’t see well enough to count them accurately—a set of dangerous-looking spikes, each two centimeters or more in length, began to extend. They didn’t come straight out, but slanted toward what looked like the rear of the organism. The last quarter of its length remained smooth, and ’Ao held it in one hand by this “tail.”

With the other she groped around the iron-finder’s bulge, exploring a circle about a meter in radius around its top. After a minute or two of this a smaller bulge swelled on the slimy surface and at its top a sphincterlike opening appeared. With far more care than she had displayed up to this point, the child brought the spiny whatever-it-was close to the mouth—or whatever-it-was—and carefully suspended it, still by the tail, so that the outer curve of each of the “forward” spikes would touch the rim of the opening at the same moment if she lowered it much farther.

For the first time, she hesitated and looked at Keo. Even Mike could understand the answer—an encouraging circle-and-three-finger gesture of the gloved right hand. The child’s facial expression could of course not be seen, but both men could imagine the firmly compressed lips and fixed gaze as she very slowly eased the thing, which seemed to be a good deal denser than the surrounding water, downward again.

With only millimeters to go, her hand shook slightly, but she didn’t jerk it upward; she merely stopped, steadied herself, and resumed the letdown. Keo repeated the approval gesture, and an instant later contact was made.

As far as the visitor could tell, it was simultaneous all around the opening, though he had no idea why this should be important. For several seconds nothing more happened. ’Ao’s hand remained steady—unbelievably so, to Mike. Then a ring-shaped film of tissue pouted away from the opening and contracted around the first three or four rows of hooks. ’Ao let go, and almost instantly the spiky “fish” was swallowed and the opening closed. Thirty seconds later the smaller bulge had flattened to match the curvature of the big one, and the child relaxed visibly.

The job was not quite done, it seemed; the two knowledgeable watchers kept on watching, and Mike followed their example.

Nothing really obvious happened for something like a quarter of an hour. Then the top of the big bulge began to sink, along with a meridian stripe now visible on each side of it. Soon even Mike could tell that the bulge was dividing, and guess what was happening. The meridional groove grew deeper and wider, and when its depth had reached ten or fifteen centimeters Keo rested a hand on the child’s armored shoulder and waved presumably toward Malolo, though Mike was no longer sure of direction. He did not yet keep mental track of the sister world or the suns as a matter of habit.

They began swimming. The dividing bulge vanished behind them and presently the ship could be seen ahead. The Terrestrial wondered, as he had several times in the last day or two, whether the Kainuian sense of direction was simply an incredible memory for details, a habit of keeping aware of the few visible celestial bodies, or something more subtle.

He had no reason to believe that there was any local technology unknown on the older human-inhabited worlds, and ordinary communication equipment worked very poorly indeed on this planet; the ubiquitous thunderheads and charged haze droplets blocked or quickly damped out all electromagnetic transmission of much longer wavelength than visible light, even when frequency modulated. Only Muamoku had lights bright enough to guide a space craft to a specific point on the surface from directly above; none of the other floating cities could, or wanted to, spare the energy. He had not asked Wanaka or Keo why even Muamoku bothered—probably the reasons were economic—and didn’t plan to. The miners might not know, and might dislike showing ignorance as much as Mike himself did. He had no wish to make himself unwelcome, at least until his own project was done. Tact, he often pointed out when the subject arose, would have been his middle name if he had had one, and to him tact meant talking as little as possible when he wasn’t sure what to say.

They climbed aboard and doffed helmets.