Noise

by Hal Clement

  Another of the huge floating mysteries was sighted in the next few days. Wanaka steered Mata as close as even she dared, but that was not enough to let them see any significant difference from the first one. ’Oloa, on request, reported that they were just forty-five degrees from the equator, plus or minus its—or her, as Mike was beginning to think—current accumulated three-minute uncertainty, but Wanaka said nothing more about working back to city latitudes. Keo asked no questions, and Mike of course followed—or possibly had furnished—this example. ’Ao, he had decided, really didn’t care in the least where they went or how long they took, as long as she could earn an occasional few points toward adulthood. She was not exactly kept at the masthead by orders, but knew it was the most likely place to spot something useful. She would descend to eat, sleep, and salvage hailstones for the water breakers, or to sweep the deck clear of them if these were full, but that was about all. Her conversational needs seemed to be satisfied by the doll.

  Kaihapa, the twin world, was now almost at the western horizon. Kainui’s low haze made the other planet’s equatorial cloud belt—it matched climate zones closely with its slightly larger sister—almost indistinguishable; the crew now had to look through too much of their own world’s atmosphere. Its polar regions, where, as on Kainui, floe ice accumulated and raised the local albedo, were also hard but not impossible to distinguish. The apparent location of these features gave a very rough confirmation of Mata’s latitude, of course, but ’Oloa was much more reliable. Now that Mike had learned the doll’s nature and purpose, it—she—was frequently consulted.

  Days later still, and well south of latitude minus forty-five, there appeared yet another of the big mysteries. This one, however, did not rise nearly as high above the sea or appear nearly so spherical as the earlier ones, and ’Ao reported it as “something big” rather than a city. Wanaka, staring unblinkingly at it, shifted Mata’s heading to an almost straight-in approach. Mike was not alone in imagining a firm-set expression on the hidden mouth. None of them needed imagination to see that this thing was far lighter in color than the others and had many more of the bright, sparkling points that had proven in the others to be ice.

  The general opinion, voiced by Keo, was that this was actually much like the others but had recently completed a turnover. Approaching it should be relatively safe.

  No one wondered seriously why, if it had just turned over as a result of its formerly submerged ice’s melting, it should now be lighter in color than the earlier ones. Mike, without the benefit of anyone else’s opinion, guessed privately that since they were farther from the equator there might have been more ice in the mixture to start with.

  The captain again ordered the doll to calculate as best it could how far into the deep currents this one reached. She got the same nonanswer as before, more quickly this time. The currents were only known very loosely, as calculated from their latitude and generally accepted circulation theory; the depth the object might draw was completely unguessable.

  By this time even ’Ao knew about simultaneous equations. She had proved it with a navigation solution—done in her head, to Hoani’s astonishment but no one else’s, apparently—and now boasted several more points on her suit and displayed correspondingly higher morale. She had admitted to him once, when the others were out of hearing, that she hoped sometime to be the youngest shipmaster in history. Mike had, of course, no idea how much farther she had to go along this course, and the child herself was not very specific on the point. He couldn’t help wonder just how clear she was herself about it. By his standards she was a ten-year-old, with a ten-year-old’s vague ideas about adulthood; but her education had certainly followed a different course from that of his own childhood back on Earth. He couldn’t guess what and how much she still had to learn.

  No one was greatly worried about overturn risks as they approached the floating object, which was now looking less and less like a city and more and more like a very dirty and wave-worn iceberg. In spite of this change, Wanaka had again ordered ’Ao to keep alert for signs of people and water craft. Everyone else did the same from deck level without orders.

  And without success.

  There was far less flotsam this time as they approached under greatly reduced sail—Keo and Mike were kept busy trimming, following the captain’s orders from her own station at the tiller. These were sometimes vocal and sometimes in Finger, as the thunder far overhead varied in volume. It was no accident that symbols in that language that had to do with ship handling could always be managed by one—either—hand. What small floating objects there were seemed to consist, to everyone’s surprise, of nearly pure ice. There was coral in occasional pieces of this, but it was lighter in color, much closer to yellow than the dark red they had seen earlier, and surprisingly regular in size and shape. It was much less fragile, too; at Wanaka’s order, Mike gathered several specimens and had no trouble this time with their breaking up.

  Keo had been watching very carefully on his own initiative for what he had seen earlier—any signs that this big mass might be rising, however slowly; but they hove to only a few dozen meters from the huge but apparently uninhabited object with no reason other than recent memory to make them worry.

  “Keo, the water is very shallow; the ice goes out a lot farther from the water line than we are. Toss two grapnels. Bow and stern.” The mate complied without comment. Wanaka gestured ’Ao down to the deck, without bothering to look up herself. All remained silent for some minutes, examining every detail close enough to be seen clearly through the haze. Mike, still much more conscious of each thunderclap than any native, focused his own attention on items that looked less stable than most, wondering what effect the heavy sound waves might have on them. There were actually very few such features; he felt pretty sure that, however stable the whole mass might be, the lower parts they could now see had spent some time close enough to the water line to have experienced wave action. Most irregularities seemed rounded.

  The few exceptions even he could explain. They were far up, almost too high for details to show, but they were possible pits and certainly fragments and shatter marks that might have been left by explosions.

  This did not have to indicate habitation, recent or otherwise; as far as he had heard, chemical explosives were not used on Kainui. He had certainly never heard a word recognizably close to that meaning in any locally spoken language, and couldn’t offhand think of any use for such material here—though that, he realized, was not a reliable guide. There would always be lots he didn’t know about the Kainui people.

  The explosions could be natural, though. The lowest few hundred meters of Kainui’s atmosphere was much too good a conductor to allow electrical charge to build up locally; all the lightning was higher, ordinarily cloud-to-cloud. ’Ao’s normal duty station was perfectly safe. The organically grown cities, however, had to be grounded to salt water; that, he knew, was one of the principal uses of copper on the planet. The grounds didn’t last very long; they corroded, melted, or otherwise succumbed to electrochemical action.

  This city-sized object seemed to extend quite far enough above sea level to be vulnerable to lightning, and lightning striking a surface composed largely of ice would certainly experience explosions. Mike began looking for items that might represent scattered fragments on the lower, presumably wave-smoothed areas.

  He said nothing, as usual, hoping that one of the others might make a remark that would tell him how far his planetary ignorance was misguiding him.

  The captain eventually spoke, but not very helpfully.

  “Mike, I’ve heard that ice is more slippery than a wet deck, even on slopes. Do you have any experience with it?”

  “Yes. Lots. You get it on Aotearoa’s South Island, which has many high mountains. I’m a good—” he paused, and had to spend a minute or two getting the basics of skiing and the meaning of “mountain” and the differences between snow and ice across to his listeners. Wanaka finally nodded.

  “
Will it be hard or dangerous to walk or climb on this thing, then?”

  “Quite likely. If there are enough small chips of the coral mixed in as there seemed to be in the others it may be safe enough, but all we’ve seen here are pretty big. I suggest you let me try it first. If I do slip, at least I won’t be taken by surprise.”

  “Neither will I,” interjected ’Ao. “I’ve slipped on deck lots of times.”

  “On a deck with lots of grab lines, and which is rocking so that downhill turns to uphill before you’ve gone very far. Do you think you’d be safe on one that kept you going downhill for thirty of forty ship lengths, interrupted here and there by a piece of coral big enough and sharp enough and hard enough, if the ones we’ve been picking up here are any indication, to rip off half your armor as you went by—toward the water?”

  The child seemed unconvinced, but the captain wasn’t.

  “How safe will you be?” she asked Hoani. He shrugged, though his noise armor concealed the gesture pretty well.

  “Not perfectly, of course. Who expects to be? At home, I’d carry a small pointed axe, or even two, to get a grip if I did start to slide, and I might have metal points strapped to my feet to forestall it. We don’t have anything like that on board, though I suppose those people you mentioned who tried to build and sell icebergs probably did. But look at the shape of these bits of coral; they’re fair-sized cylinders with pointed ends. Spikes, of a sort. I could use them pretty well as ice axes, though it would be nicer if they had real handles. I suggest I go ashore on the flattest place we can find, and look for some more; I want to find out why the ones we’ve been finding near this ice are all so uniform. I’m getting an idea about that.” He paused, not for breath since he was using Finger, but to his relief Wanaka didn’t ask for details. “If my suit gets a few cuts and scratches, they’ll heal, after all.”

  The captain hesitated. Both Mike and Keo could practically read her mind, though neither could guess which tack she’d take.

  “All right,” she said at last rather slowly. “Hook on a safety line, though. You’re not going to climb far. Keo, hold the other end, but give him plenty of slack. If you pull him off his feet you’ll make at least two enemies.”

  “Three,” said ’Ao.

  “If I go off my feet, the chances are it won’t be Keo’s fault,” Mike pointed out. “But do give me lots of slack. Even if I do slip there’ll be no need to haul in until I reach the water, if I haven’t stopped myself sooner, and not much then unless I’ve been knocked out.”

  “You mean you’re going to keep your helmet open?” asked ’Ao in tones suggesting shock.

  Mike paused. “I was. I hadn’t thought of that. Thanks. The work would be a lot easier with it open, but I’d just as soon live through it, and getting it closed while I’m sliding downhill could be awkward. It would certainly get in the way of trying to stop the slide.”

  ’Ao’s own reflexes in such a situation would have been wholly concerned with her helmet, so this sentence also startled her; but she said nothing. Having caught an adult in one error was enough for a few days. The second one, after all, might have some sense behind it; she herself had never slid downhill, since Muamoku used railed stairs rather than ramps between levels, and could only guess what it might feel like. The remark about tearing armor also deserved some thinking, even if armor did eventually heal itself. Eventually did not mean instantly.

  Wanaka would have been very happy to read the child’s mind just then. It seemed as though the loss of points she had taken so indignantly so many weeks before had indeed been good for her.

  Mike was able to give an immediate demonstration of the problems of climbing a slippery slope. He couldn’t even get out of the sea until he had found, after some search and extracted after some effort from the submerged ice near the shoreline, two pieces of imbedded coral, each about twice the volume of a fist, in the ice just below the water line. Conveniently and, to everyone involved most interestingly, they were almost exactly the same shape as those picked up floating in the last few minutes and that were still on board—rods small enough in diameter to be held in a gloved hand, and sharp and hard enough to be usable as crude ice axes. With these Hoani dragged himself away from the water’s edge and a short distance farther, to where the slope became almost level over a few square meters. There he succeeded without too much trouble in rising to his feet.

  To the captain’s unexpressed impatience, he examined his surroundings for several minutes before reporting any details. When he finally began to talk, stowing his pieces of coral in two of the tool loops in his noise armor to free his hands, he raised more questions than he answered.

  “The ice I can see through, this flat part, is full of coral just like my pieces. Same size, same shape. They average half a meter to a meter apart, they’re all lying horizontally and, within a few degrees, parallel to each other. My first thought is that we’d better look around for people.”

  “Mine is that this thing has been grown,” Wanaka answered. Mike was relieved; this was the suspicion he had been hoping not to have to voice. “Are any of the rods really close beneath the surface you’re standing on?”

  “Yes. A dozen or more have less than a centimeter of ice over them.”

  “Then get down as close to one or two of them as you can. Look for details around them, especially threads connecting any of them to their neighbors. And look over the ones you have at your belt for anything similar. ’Ao, hook on to a safety line—I’ll hold it—and swim over there. Don’t try to climb out of the water, but look for more of those things where it’s shallow. They should be as near to the surface of the ice as possible. I want to melt some of them out without breaking anything.”

  “How would we do that?” asked Hoani, who had kept his eyes on the captain’s fingers rather than immediately following her orders. She had looked back at him as ’Ao had leaped for a length of cord, and saw the question.

  “I’ll show you when we do it. Do your own job now.”

  This was as near as the captain had yet come to addressing him as tersely and impersonally as an ordinary crew member; Mike felt more pleased than embarrassed. The embarrassment would no doubt come later, when he was shown or told about the melting technique and realized he should have guessed it for himself. The effort to guess took some of his attention from his work, but fortunately Wanaka couldn’t see this. He hoped the child would not find a spicule, if that were an appropriate word for the things, too quickly; the longer she took, the better his chances of—

  His safety line jerked twice. He looked toward the ship. Keo stopped pulling the line, and Wanaka shifted to Finger.

  “’Ao’s found one of them just starting to float. I suppose they’re melting out all the time. There—she has another. You needn’t spend time on the ones still under ice, at least for a while. Try climbing some more—no, come back here. Keo would have to keep an eye on you, and I want everyone to look these things over. Even you. You have no experience with anything like it, I suppose, but that could turn out to be useful.”

  Mike obeyed, closing his helmet again and allowing himself to slide the few meters to the water’s edge. By the time he was standing on Mata’s deck, ’Ao was there, too, holding the objects she had picked up in each hand. The captain addressed her vocally.

  “Keo and I will hold them. Take the lens and look for any trace you can find of anything even slightly like fine hair or any other fiber. Remember what Mike said and what you saw; these things are lined up with each other in the ice. I want to know whether they’re connected with each other in any way.”

  “I didn’t think of that,” ’Ao replied. “If they were, I probably broke the fibers when I brought them over.”

  “Maybe, but you said they’d started to float. Don’t worry about it. If you did, they’re probably sticking to the sides of the pieces, since everything there is wet. Mike may have to go back over there to study the ones still in the ice, but we’ll try this way first.”
/>   “May I go with him this time?”

  “Maybe. If you do see anything here, I’ll want you to look for the same thing still in the ice. If you don’t, maybe I’ll want you to look anyway.”

  Mike silently admired the captain’s technique, but concerned himself more with what details he could see on the spicule the child wasn’t examining. He could spot nothing remarkable without the lens, other than a vague pattern that might have been scales or shingles on the main body of the cylinder. Even the lens, when his turn came to use it, showed him nothing more. There seemed little doubt that the captain was right about the objects being some form of pseudolife, but there was no sign of material connection at least between these two specimens. It was back to the main berg.

  ’Ao accompanied Hoani. So did Keokolo. Safety lines connected them—’Ao and Keo to Mike, the heaviest—but not to the ship, where Wanaka remained. The three reached the nearly level area that Mike had examined earlier and took turns applying the lens to the rods of coral that were close enough to the ice surface to be inside its focus. None could see anything running from any one of them to another; either the connections, if they existed at all, were too fine to be seen, or were of some more subtle type. All of them, including ’Ao, were familiar enough with pseudobiology to know the possibility of solute gradients around one “organ” controlling the growth and even the orientation of the next. They finally reported their lack of success, and even the obvious conclusions, to the captain, and without consulting either her or each other began to climb. Mike used the spicules he had collected earlier as ice axes. Keo and the child imitated him with ones they had picked up from the sea before climbing aboard the berg.