by Hal Clement
The white cloud reappeared at once, but this time grew and spread. It enveloped the near side of the Kwembly, including the bridge, blocking the view for Dondragmer and the communicator lens. Illuminated by the outside flood lamps, it caught the attention of the crew, now nearing the edge of the valley, and of Stakendee and his men miles to the west. This time the entire length of the wire was submerged in melted ice, which bubbled away from around it as hot vapor, condensed to liquid a fraction of a millimeter away, evaporated again much less violently from the surface of the widening pool, and again condensed, this time to ice, in the air above. The steaming pool, some three quarters of the Kwembly‘s length and originally some six feet in width, began to sink below the surrounding ice as its contents were borne away as ice dust by the gentle wind faster than they were replenished by melting.
One side of it reached the cruiser, and Dondragmer, catching a glimpse of it through a momentary break in the swirling fog, suddenly had a frightening thought. He donned his airsuit hurriedly and rushed to the inner door of the main lock. Here he hesitated; with the suit’s protection he could not tell by feel whether the ship was heating dangerously, and there were no internal thermometers except in the lab. For a moment he thought of getting one; then he decided that the time needed might be risky, and opened the upper safety valves in the outer lock, which were handled by pull-cords from inside reaching down through the liquid trap. He did not know whether the heat from outside would last long enough to boil ammonia in the lock itself—the Kwembly‘s hull was well insulated, and leakage would be slow—but he had no desire to have boiling ammonia confined aboard his command. It was actually an example of a little knowledge causing superfluous worry; the temperature needed to bring ammonia’s vapor pressure anywhere near the current ambient value would have made an explosion the least of any Mesklinite’s concerns. However, no real harm was done by opening the valves, and the captain felt better as a result of the action. He returned hastily to the bridge to see what was going on.
A gentle breeze from the west was providing occasional glimpses by sweeping the ice fog aside, and he could see that the level of the molten pool was lower. Its area had increased greatly, but as the minutes passed he decided that some sort of limit had been reached in that respect. His two men were visible at times, crawling here and there trying to find a good viewpoint. They finally settled down almost under the bridge, with the breeze behind them.
For some time even the liquid level seemed to reach a steady state, though none of the watchers could understand why. Later they decided that the spreading pool had melted its way into the still-liquid reservoir under the Kwembly, which took fully fifteen minutes to evaporate. By the end of that time, cobbles from the river bottom began to show their tops above the simmering water, and the problem of turning the power unit off before another length of wire was destroyed suddenly occurred to Dondragmer.
He knew now that there was no danger of the power unit blowing up; however, several inches of the wire had already melted away, and there was going to be trouble restoring the refrigerator to service. This situation should not be allowed to get any worse, which it would if more metal were lost. Now, as the water level reached the cobbles and the wire ceased to follow the melting ice downward, the captain suddenly wondered whether he could get out to the controls fast enough to prevent the sort of shut-off which had occurred before. He wasted no time mentally blasting the scientists for not attaching a cord to the appropriate controls; he hadn’t thought of it in time either.
He donned his suit again and went out through the bridge lock. Here the curve of the hull hid the pool from view, and he began to make his way down the holdfasts as rapidly as he could in the poor visibility. As he went, he hooted urgently to Borndender, “Don’t let the wire melt again! Turn off the power!”
An answering, but wordless, bellow told him that he had been heard, but no other information came through the white blankness. He continued to grope his way downward, finally reaching the bottom of the hull curve. Below him, separated from his level by the thickness of the mattress and two thirds the height of the trucks, was the gently steaming surface of the water. It was not, of course, actively boiling at this pressure; but it was hot even by human standards, and the captain had no illusions about the ability of an airsuit to protect him from it. It occurred to him, rather late, that there was an excellent chance that he had just cooked his two missing helmsmen to death, but this was a passing thought; there was work to be done.
The power box lay well aft of his present position, but the nearest surface on which he could walk had to be forward. Either way there was going to be trouble reaching the unit, now presumably well surrounded by hot water; but if jumping were going to be necessary, the hull holdfasts were about the poorest possible takeoff point. Dondragmer went forward.
This brought him into clear air almost at once, and he saw that his two men were gone. Presumably they had started around the far side of the pool in the hope of carrying out his order. The captain continued forward, and in another yard or two found it possible to descend to solid ice. He did so, and hastened on what he hoped was the trail of his men.
He had to slow down almost at once, however, as his course brought him back into the ice fog. He was too close to the edge of the pool to take chances. As he went he called repeatedly, and was reassured to hear each hoot answered by another. At least, his men had not yet fallen in.
He caught up with them almost under the cruiser’s stern, having walked entirely around the part of the pool not bounded by the hull. None of them had accomplished anything; the power unit was not only out of reach but out of sight. Jumping would have been utter lunacy, even if Mesklinites normally tended to think of such a thing. Borndender and his assistant had not, and the idea had only occurred to Dondragmer because of his unusual experiences in Mesklin’s low-gravity equatorial zone so long before.
But there could not be much more time. Looking over the edge of the ice, the three could catch glimpses of the rounded tops of the rocks, separated by water surfaces which narrowed as they watched. The wire must be practically out of water by now; chance alone would not have let it settle between the stones to a point much lower than their average height, and the protecting water was already there. The captain had been weighing the various risks for minutes; without further hesitation, and without issuing any orders, he slipped over the edge and dropped two feet to the top of one of the boulders.
It was the energy equivalent of an eight-story fall on Earth, and even the Mesklinite was jolted. However, he retained his self-command. A single hoot told those above that he had survived without serious injury, and warned them against following in case pride might have furnished an impulse which intelligence certainly would not. The captain, with that order issued, relegated the scientists to the back of his mind and concentrated on the next step.
The nearest rock with enough exposed area to accommodate him was two feet—well over a body length—away, but it was at least visible. Better still, another one only slightly off the line to it exposed a square inch or so of its surface; and two seconds after analyzing this situation, Dondragmer was two feet closer to the power box and looking for another stopping point. The lone square inch of the stepping stone had been touched by perhaps a dozen feet as the red-and-black length of his body had ricocheted from it to the second rock.
The next stage was more difficult. It was harder to be sure which way to go, since the hull which had furnished orientation was now barely visible also, there were no more large surfaces as close as the one from which he had come. He hesitated, looking and planning; but before he reached a decision the question was resolved for him. The grumbling sound which had gone on for so many minutes as water exploded into steam against the hot wire and almost instantly collapsed again under Dhrawn’s atmospheric pressure abruptly ceased, and Dondragmer knew that he was too late to save the metal. He relaxed immediately and waited where he was while the water cooled, the evaporation sl
owed, and the fog of ice crystals cleared away. He himself grew uncomfortably warm, and was more than once tempted to return the way he had come but the two-foot climb up an ice overhang with hot water at its foot, which would form part of the journey, made the temptation easy to resist. He waited.
He was still alive when the air cleared and crystals of ice began to grow around the edges of the rocks. He was some six feet from the power unit, and was able to reach it by a rather zigzag course over the cobbles once the way could be seen. He shut off the power controls, and only when that was done did he look around.
His two men had already made their way along the ice cliff to a point about level with the original front bend of the wire; Dondragmer guessed that this must be where the metal had melted through this time.
In the other direction, under the bulking hull, was a black cavern where the Kwembly‘s lights did not reach. The captain had no real wish to enter it; it was very likely that he would find the bodies of his two helmsmen there. His hesitation was observed from above.
“What’s he waiting there at the power box for?” muttered McDevitt. “Oh, I suppose the ice isn’t thick enough for him yet.”
“That’s not all of it, I’d guess.” Benj’s tone made the meteorologist look sharply away from the screen. “What’s the matter?” he asked. “You must know what’s the matter. Beetch and his friend were under there. They must have been. How could they have gotten away from that hot water? I bet the captain only just thought of it—he’d never have let them use that way if he’d seen what would happen, any more than I would have.”
McDevitt thought rapidly; the boy wouldn’t be convinced, or even comforted, by anything but sound reasoning, and McDevitt’s soundest reasoning suggested that Benj’s conclusion was probably right. However, he tried.
“It looks bad, but don’t give up. It doesn’t look as though this thing melted its way all the way across under the ship, but it might have; and either way there’s some hope. If it did, they could have got out the other side, which we can’t see; if it didn’t, they could have stayed right at the edge of the liquid zone, where the ice could have saved them. Also, they may not have been under there.”
“Water ice save them? I thought you said that this stuff froze because it lost its ammonia, not because the temperature went down. Water ice at its melting point—zero centigrade—would give heatstroke to a Mesklinite.”
“That was my guess,” admitted the meteorologist, “but I’m certainly not sure of it. I don’t have enough measurements of any sort. I admit your little friend may have been killed; but we know so little of what has happened down there that it would be silly to give up hope. Just wait—there’s nothing else to do at this distance anyway. Even Dondragmer is staying put. You can trust him to check as soon as it’s possible.”
Benj restrained himself, and did his best to look for bright possibilities; but the eye he was supposed to be keeping on Stakendee remained fixed on the captain’s image.
Several times Dondragmer could be seen to extend part of his length onto the ice, but each time he drew back again, to the boy’s intense annoyance. At last, however, he seemed satisfied that the ice would hold his weight, and inch by inch extended himself entirely onto the newly frozen surface. Once off the power box he waited for a moment as though expecting something to happen; but the ice held, and he resumed his way toward the side of the Kwembly. The human beings watched, Benj’s fists clenched tightly and even the man more tense than usual.
Of course they could hear nothing. Not even the hoot which suddenly echoed across the ice penetrated the bridge to affect their communicator. They could not even guess why Dondragmer suddenly turned back from the hull as he was about to disappear under it. They could only watch as he raced back across the ice to a point just below his two men and waved excitedly at them, apparently indifferent to whatever there was to be learned about the fate of his helmsman and Benj’s friend.
XII
Dondragmer was far from indifferent, but by his standards it was normal to focus attention on a new matter likely to require action rather than clear up an old one where action was unlikely to help. He had not dropped the fate of his men from mind, but when a distant hoot bore the words: “Here’s the end of the stream” to him his program changed abruptly and drastically.
He could not see where the voice was coming from, since he was two feet below the general surface, but Borndender reported glimpses of a light perhaps half a mile away. At the captain’s order, the scientist climbed the hull part way to get a better view, while his assistant went in search of a rope to get the captain out of the ice pit. This took time. The sailors had, with proper professional care, returned the lines used in lowering the radiator bar to their proper places inside the cruiser; and when Skendra. Borndender’s assistant, tried to get through the main lock he found it sealed by a layer of clear ice which had frozen a quarter of an inch thick on the starboard side of the hull, evidently from the vapor emitted by the hot pool. Fortunately most of the holdfasts were projecting far enough through this to be usable, so he was able to climb on up to the bridge lock.
Meanwhile, Borndender called down that there were two lights approaching across the riverbed. At the captain’s order, he howled questions across the thousand-yard gap, and the two listened carefully for answers—even Mesklinite voices had trouble carrying distinct words for such a distance and through two layers of airsuit fabric. By the time Dondragmer was out of the hole, they knew that the approaching men were the part of Stakendee’s command which had been ordered to follow down the stream, and that they had reached its end less than a mile from the ship; but until the group actually reached them, no further details could be made out.
Even then, they could not entirely understand it; the description did not match anything familiar to them.
“The river stayed about the same size all the way down,” the sailors reported. “It wasn’t being fed from an; where, and didn’t seem to be evaporating. It wound among the stones a lot, when it got down to where they were. Then we began to run into the funniest obstructions. There would be a sort of dam of ice, with the stream running around one end or the other of it. Half a cable or so farther on there’d be another dam, with just the same thing happening. It was as though some of it froze when it met the ice among the stones, but only the beginning part. The water that followed stayed liquid and went on around the dam until it found some ice. The dams would build up to maybe half a body length high before the following water would find its way around We reached the last one, where it was still happening, just a few minutes ago. We’d seen the bright cloud rising over the ship before that, and wondered whether we ought to come back in case something was wrong; but we decided to carry out orders at least until the river started to lead us away from the Kwembly again.”
“Good,” said the captain. “You’re sure the stream wasn’t getting any bigger?”
“So far as we could judge, no.”
“All right. Maybe we have more time than I thought, and it isn’t a forerunner of the same thing that brought us here. I wish I understood why the liquid was freezing in that funny way, though.”
“We’d better check with the human beings,” suggested Borndender, who had no ideas on the matter either, but preferred not to put the fact too bluntly.
“Right. And they’ll want measurements and analyses. I suppose you didn’t bring a sample of that river,” he said, rather than asked, the newcomers.
“No, sir. We had nothing to carry it in.”
“All right. Born, get containers and bring some back; analyze it as well and as quickly as you can. One of these men will guide you. I’ll go back to the bridge and bring the humans up to date. The rest of you get tools and start chipping ice so we can use the main lock.”
Dondragmer closed the conversation by starting to climb the ice-crusted hull. He waved toward the bridge as he went, assuming that he was being watched and perhaps even recognized.
Benj and McDevi
tt had managed to keep track of him, though neither found it easy to tell Mesklinites apart, and were waiting eagerly when he reached the bridge to hear what he had to say. Benj in particular had grown even more tense since the search under the cruiser had been interrupted; perhaps the helmsmen had not been there after all—perhaps they had been among the newcomers who had arrived to interrupt the search—perhaps—perhaps . . .
McDevitt was a patient man by nature and liked the youngster, but even he was getting irritated by the time Dondragmer’s voice reached the station.
The report fascinated the meteorologist, though it was no consolation to his young companion. Benj wanted to interrupt with a question about Beetchermarlf, but knew that it would be futile; and when the captain’s account ended, McDevitt immediately began to talk.
“This is not much more than a guess, Captain,” he began, “though perhaps your scientist will be able to stiffen it when he analyzes those samples. It seems possible that the pool around you was originally an ammonia-water solution—we had evidence of that before—which froze, not because the temperature went down, but because it lost much of its ammonia and its freezing point went up. The fog around you just before this whole trouble started, back on the snowfield, was ammonia, your scientists reported; I’m guessing that it came from the colder areas far to the west. Its droplets began to react with the water ice, and melted it partly by forming a eutectic and partly by releasing heat—you were afraid of something of that sort even before it happened, as I remember. That started your first flood. When the ammonia cloud passed on into Low Alpha, the solution around you began to lose ammonia by evaporation, and finally the mixture which was left was below its freezing point. I’m guessing that the fog encountered by Stakendee is more ammonia, and provided the material for the rivulet he found. As it meets the water ice near you they dissolve mutually until the mixture is too dilute in ammonia to be liquid any more—this forms the dam your men described, and the liquid ammonia still coming has to find a way around. I would suggest that if you can find a way to divert that stream over to your ship, and if there proves to be enough of it, your melting-out problem would be solved.” Benj, listening in spite of his mood, thought of wax flowing from a guttering candle and freezing first on one front and then another. He wondered whether the computers would handle the two situations alike, if ammonia and heat were handled the same way in the two problems.
