by Hal Clement
“What’s the use? The only other charges we had were in the tractor. Thank goodness they were nuclear instead of H. E. If it didn’t work we’d have more trouble to get back than we’re having now.”
“If it didn’t work, is there any point in going back?”
“Stop quibbling and keep walking. Dr. Burkett, are you listening?”
“Yes, Captain.”
“We’re fresh out of tractors, but if you want to try it on foot you might start a set of flow measures on the lava. Arnie wants to know whether our landslide slid properly.”
However, the two were able to tell for themselves before getting back to the Albireo.
The flow didn’t stop all at once, of course; Nit with the valley feeding it blocked off by a pile of volcanic ash four hundred feet high on one side, nearly fifty on the other and more than a quarter of a mile long, its enthusiasm quickly subsided. It was thin, fluid stuff, as Burkett had noted; but as it spread it cooled, and as it cooled it thickened.
Six hours after the blast it had stopped with its nearest lobe almost a mile from the ship, less than two feet thick at the edge.
When Mardikian’s tractor arrived, Burkett was happily trying to analyze samples of the flow, and less happily speculating on how long it would be before the entire area would be blown off the planet. When Marini’s and Harmon’s vehicles arrived, almost together, the specimens had been loaded and everything stowed for acceleration. Sixty seconds after the last person was aboard, the Albireo left Mercury’s surface at two gravities.
The haste, it turned out, wasn’t really necessary. She had been in parking orbit nearly forty-five hours before the first of the giant volcanoes reached its climax, and the one beside their former site was not the first. It was the fourth.
“And that seems to be that,” said Camille Burkett rather tritely as they drifted a hundred miles above the little world’s surface. “Just a belt of white-hot calderas all around the planet. Pretty, if you like symmetry.”
“I like being able to see it from this distance,” replied Zaino, floating weightless beside her. “By the way, how much bonus should I ask for getting that idea of putting the seismic charges to use after all?”
“I wouldn’t mention it. Any one of us might have thought of that. We all knew about them.”
“Anyone might have. Let’s speculate on how long it would have been before anyone did.”
“It’s still not like the other idea, which involved your own specialty. I still don’t see what made you suppose that the gas pillar from the volcano would be heavily charged enough to reflect your radio beam. How did that idea strike you?”
ZAINO THOUGHT back, and smiled a little as the picture of lightning blazing around pillar, cloud and mountain rose before his eyes.
“You’re not quite right,” he said. “I was worried about it for a while, but it didn’t actually strike me.”
It fell rather flat; Camille Burkett, Ph.D., had to have it explained to her.
1965
RAINDROP
Harmless little Raindrop! It was life or death to one human, and feast or famine to the race!
I
“It’s not very comfortable footing, but at least you can’t fall off.”
Even through the helmet phones, Silbert’s voice carried an edge that Bresnahan felt sure was amused contempt. The younger man saw no point in trying to hide his fear; he was no veteran of space and knew that it would be silly to pretend otherwise.
“My mind admits that, but my stomach isn’t so sure,” he replied. “It can’t decide whether things will be better when I can’t see so far, or whether I should just give up and take a running dive back there.”
His metal-clad arm gestured toward the station and its comfortable spin hanging half a mile away. Technically the wheelshaped structure in its synchronous orbit was above the two men, but it took careful observing to decide which way was really “up.”
“You wouldn’t make it,” Silbert replied. “If you had solid footing for a jump you might get that far, since twenty feet a second would take you away from here permanently. But speed and velocity are two different animals. I wouldn’t trust even myself to make such a jump in the right direction—and I know the vectors better than you do by a long shot. Which way would you jump? Right at the station? Or ahead of it, or behind it? And which is ahead and which is behind? Do you know?”
“I know which is ahead, since I can see it move against the star background, but I wouldn’t know which way to jump. I think it should be ahead, since the rotation of this overgrown raindrop gives us less linear speed than the station’s orbit; but I wouldn’t know how far ahead,” Silbert said.
“Good for you.” Bresnahan noted what he hoped was approval in the spaceman’s tone as well as in his words. “You’re right as far as you committed yourself, and I wouldn’t dare go any farther myself. In any case, jumping oft this stuff is a losing game.”
“I can believe that. Just walking on it makes me feel as though I were usurping a Biblical prerogative.”
The computerman’s arm waved again, this time at the surface underfoot, and he tried to stamp on it at the same moment. The latter gesture produced odd results. The material, which looked a little like clear jelly, gave under the boot but buldged upward all around it. The bulge moved outward very slowly in all directions, the star patterns reflected in the surface writhing as it passed. As the bulge’s radius increased its height lessened, as with a ripple spreading on a pond. It might have been an ultra-slow motion picture of such a ripple, except that it did not travel far enough. It died out less than two yards from Bresnahan’s foot, though it took well over a minute to get that far.
“Yeah, I know what you mean. Walking on water was kind of a divine gift, wasn’t it? Well, you can always remember we’re not right on the water. There’s the pressure film, even if you can’t see it.”
“That’s so. Well, let’s get on to the lock. Being inside this thing can’t be much worse than walking around on its surface, and I have a report to make up.” Silbert started walking again at this request, though the jelly-like response of the water to his footfalls made the resulting gait rather odd. He kept talking as he led the way.
“How come that friend of yours can’t come down from the station and look things over for himself? Why should you have to give the dope to him second-hand? Can’t he take weightlessness?”
“Better than I can, I suspect,” replied Bresnahan, “but he’s not my friend. He’s my boss, and pays the bills. Mine not to reason why, mine but to act or fry. He already knows as much as most people do about Raindrop, here. What more he expects to get from me I’m not sure. I just hope that what I can find to tell him makes him happy. I take it this is the lock.”
They had reached a disk of metal some thirty feet in diameter, projecting about two feet from the surface of the satellite. It continued below the surface for a distance which refraction made hard to estimate.
Its water line was marked by a ring of black, rubbery-looking material where the pressure film adhered to it. The men had been quite close to it when they landed on Raindrop’s surface a few minutes before, but it is hard to make out landscape details on a water surface under a black, starfilled sky; the reflection underfoot is not very different from the original above. A five-mile radius of curvature puts the reflected images far enough down so that human depth perception is no help.
Waves betrayed themselves, of course, and might have shown the lock’s location—but under a gravitational acceleration of about a tenth of an inch per second squared, the surface waves raised by spacesuit boots traveled much more slowly than the men who wore them. And with their high internal energy losses they didn’t get far enough to be useful.
As a result, Bresnahan had not realized that the lock was at hand until they were almost upon it. Even Silbert, who had known about where they would land and could orient himself with Raindrop’s rotation axis by celestial reference features, did not actually see it until it was only a few
yards away.
“This is the place, all right,” he acknowledged. “That little plate near the edge is the control panel. We’ll use the manhole; no need to open the main hatch as we do when it’s a matter of cargo.”
He bent over—slowly enough to keep his feet on the metal—and punched one of the buttons on the panel he had pointed out. A tiny light promptly Hashed green, and he punched a second button.
A yard-square trap opened inward, revealing the top of a ladder. Silbert seized the highest rung and pulled himself through the opening head first—when a man weighs less than an ounce in full space panoply it makes little real difference when he elects to traverse a ladder head downward. Bresnahan followed and found himself in a cylindrical chamber which took up most of the inside of the lock structure. It could now be seen that this must extend some forty feet into the body of Raindrop.
At the inner end of the compartment, where curved and flat walls met, a smaller chamber was partitioned off. Silbert dove in this direction.
“This is a personnel lock,” he remarked. “We’ll use it; it saves flooding the whole chamber.”
“We can use ordinary spacesuits?”
“Might as well. If we were going to stay long enough for real work, we’d change—there is local equipment in those cabinets along the wall. Spacesuits are safe enough, but pretty clumsy when it comes to fine manipulation.”
“For me, they’re clumsy for anything at all.”
“Well, we can change if you want; but I understood that this was to be a fairly quick visit, and that you were to get a report back pronto. Or did I misread the tone your friend Weisanen was using?”
“I guess you didn’t, at that. We’ll go as we are. It still sounds queer to go swimming in a spacesuit.”
“No queerer than walking on water. Come on, the little lock will hold both of us.”
The spaceman opened the door manually—there seemed to be no power controls involved—and the two entered a room some five feet square and seven high. Operation of the lock seemed simple; Silbert closed the door they had just used and turned a latch to secure it, then opened another manual valve on the other side of the chamber. A jet of water squirted in and filled the space in half a minute. Then he simply opened a door in the same wall with the valve, and the spacesuited figures swam out.
This was not as bad as walking on what had seemed like nothingness. Bresnahan was a good swimmer and experienced free diver, and was used to being suspended in a medium where one couldn’t see very far.
The water was clear, though not as clear as that sometimes found in Earth’s tropical seas. There was no easy way to tell just how far vision could reach, since nothing familiar and of known size was in view except for the lock they had just quitted. There were no fishes—Raindrop’s owners were still debating the advisability of establishing them there—and none of the plant life was familiar, at least to Bresnahan. He knew that the big sphere of water had been seeded by “artificial” life forms—algae and bacteria whose genetic patterns had been altered to let them live in a “sea” so different from Earth’s.
II
Raindrop was composed of the nuclei of several small comets, or rather what was left of those nuclei after some of their mass had been used in reaction motors to put them into orbit about the earth. They had been encased in a polymer film sprayed on to form a pressure seal, and then melted by solar energy, concentrated by giant foil mirrors.
Traces of the original wrapping were still around, but its function had been replaced by one of the first tailored life forms to be established after the mass was liquid. This was a modification of one of the gelatin-capsule algae, which now encased all of Raindrop in a microscopically thin film able to heal itself after small meteoroid punctures, and strong enough to maintain about a quarter of an atmosphere’s pressure on the contents. The biological engineer who had done that tailoring job still regarded it as his professional masterpiece.
The methane present in the original comet material had been oxidized by other bacteria to water and carbon dioxide, the oxygen of course coming from normal photosynthesis. A good deal of the ammonia was still present, and furnished the principal reason why genetic tailoring was still necessary on life forms being transplanted to the weightless aquarium.
The men were drifting very slowly away from the lock, though they had stopped swimming, and the younger one asked, “How do we find our way back here if we get out of sight?”
“The best trick is not to get out of sight. Unless you want to examine the core, which I’ve never done, you’ll see everything there is to see right here. There is sonic and magnetic gear—homing equipment—in your suit if you need it, though I haven’t checked you out on its use. You’d better stay with me. I can probably show you what’s needed. Just what points do you think Weisanen wants covered?”
“Well, he knows the general physical setup—temperature, rotation, general current pattern, the nature of the skin. He knows what’s been planted here at various times; but it’s hard to keep up to date on what’s evolved since. These tailored life forms aren’t very stable toward mutation influences, and a new-stocked aquarium isn’t a very stable ecological environment. He’ll want to know what’s here now in the way of usable plants, I suppose. You know the Agency sold Raindrop to a private concern after the last election. The new owners seem willing to grant the importance of basic research, but they would sort of like a profit to report to the stockholders as well.”
“Amen. I’m a stockholder.”
“Oh? Well, it does cost something to keep supply ships coming up here, and—”
“True enough. Then this Weisanen character represents the new owners? I wonder if I should think of him as my boss or my employee.”
“I think he is one of them.”
“Hmph. No wonder.”
“No wonder what?”
“He and his wife are the first people I ever knew to treat a space flight like a run in a private yacht. I suppose that someone who could buy Raindrop wouldn’t be bothered by a little expense like a private Phoenix rocket.”
“I suppose not. Of course, it isn’t as bad as it was in the days of chemical motors, when it took a big commercial concern or a fair-sized government to launch a manned spaceship.”
“Maybe not; but with fourteen billion people living on Earth, it’s a little unusual to find a really rich individual, in the old Ford-Carnegie tradition. Most big concerns are owned by several million people like me.”
“Well, I guess Weisanen owns a bigger piece of Raindrop than you do. Anyway, he’s my boss, whether he’s yours or not, and he wants a report from me, and I can’t see much to report on. What life is there in this place besides the stuff forming the surface skin?”
“Oh, lots. You just aren’t looking carefully enough. A lot of it is microscopic, of course; there are fairly ordinary varieties of pond-scum drifting all around us. They’re the main reason we can see only a couple of hundred yards, and they carry on most of the photosynthesis. There are lots of nonphotosynthetic organisms—bacteria—producing carbon dioxide just as in any balanced ecology on Earth, though this place is a long way from being balanced. Sometimes the algae get so thick you can’t see twenty feet, sometimes the bacteria get the upper hand. The balance keeps hunting around even when no new forms are appearing or being introduced. We probably brought a few new bacteria in with us on our suits just now; whether any of them can survive with the ammonia content of Raindrop this high I don’t know, but if so the ecology will get another nudge.
“There are lots of larger plants, too—mostly modifications of the big seaweeds of Earth’s oceans. The lock behind us is overgrown with them, as you can see—you can look more closely as we go back—and a lot of them grow in contact with the outer skin, where the light is best. Quite a few are free-floating, but of course selection works fast on those. There are slow convection currents, because of Raindrop’s size and rotation, which exchange water between the illuminated outer regions and the
darkness inside. Free-floating weeds either adapt to long periods of darkness or die out fast. Since there is a good deal of hard radiation near the surface, there is also quite a lot of unplanned mutation over and above the regular gene-tailoring products we are constantly adding to the pot. And since most of the organisms here have short life spans, evolution goes on rapidly.”
“Weisanen knows all that perfectly well,” replied Bresnahan. “What he seems to want is a snapshot—a report on just what the present spectrum of life forms is like.”
“I’ve summed it up. Anything more detailed would be wrong next week. You can look at the stuff around us—there. Those filaments which just tangled themselves on your equipment clip are a good example, and there are some bigger ones if you want there—just in reach. It would take microscopic study to show how they differ from the ones you’d have gotten a week ago or a year ago, but they’re different. There will be no spectacular change unless so much growth builds up inside the surface film that the sunlight is cut down seriously. Then the selection factors will change and a radically new batch—probably of scavenger fungi—will develop and spread. It’s happened before. We’ve gone through at least four cycles of that sort in the three years I’ve worked here.”
Bresnahan frowned thoughtfully, though the facial gesture was not very meaningful inside a space helmet.
“I can see where this isn’t going to be much of a report,” he remarked.
“It would have made more sense if you’d brought a plankton net and some vacuum jars and brought up specimens for him to look over himself,” replied Silbert. “Or wouldn’t they mean anything to him? Is he a biologist or just a manager?”
“I couldn’t say.”
“How come? How can you work for him and not know that much?”
“Working for him is something new. I’ve worked for Raindrop ever since I started working, but I didn’t meet Weisanen until three weeks ago. I haven’t been with him more than two or three hours’ total time since. I haven’t talked with him during those hours; I’ve listened while he told me what to do.”
