Still River

by Hal Clement

  “Get off while you’re still on the outer slope?” cried Charley. “We can figure out how to follow the machines later, if we decide it’s worth the risk.”

  “Wait till I get to the top,” retorted Molly firmly. “At least I’m going to get a look at that hole. Bring the boat down so I can reach some of the climbing grips on the hull; that will be better than rolling back down the hillside and maybe getting buried in the sand.”

  Again Charley made no vocal objection. The boat was now almost over the center of the crater. He lowered it until the bow entrance port was about level with the rim of the cone and worked his way slowly toward the point where his friend should appear over the edge in a few seconds.

  He judged the position properly, unfortunately. Suit and cylinder appeared directly in front of him. At almost the same moment, the wind from below, deflected by the hull, raised another puff of blinding dust; the Kantrick was using long-wave pickup for his screen, but not long enough. Both he and the Human were cut off from view of each other. Simultaneously the robot swerved, in response to the change of wind, in the direction in which Molly had stepped to avoid its path. Its push was gentle—too gentle to feel at first, or in time. Joe would probably have realized he was falling soon enough to react properly; the Human, already at only a fifteenth of her normal weight, did not. By the time either she or Charley could see clearly, she was sliding down the inner sand slope, well ahead of the robot.

  The latter was following, and she made every effort to scramble up toward it, or at least to slow her descent enough to let it catch up. Charley moved the boat ahead of them and tried to lower it so as to block the paths of both, but the craft was too big. Its stern, two hundred meters away, encountered the far side of the pit and caused an unplanned dip at the bow end; Charley frantically manipulated keys to level off, forgetting for a moment that there was no absolute need to be level and that he could have blocked the hole at the bottom with the vessel’s bow. By the time this occurred to him, Molly was out of sight of his screen, and he did not dare lower for fear of crushing her with the hull until he could find her again. This took perhaps half a minute.

  She was now at the very bottom of the slope, apparently standing on something solid, with sand that she had displaced still pouring past her feet and vanishing below and the wind from the crater now marked by another rising plume of fine dust. The robot was half a dozen meters up the slope, descending straight toward her in its unhurried fashion.

  Charley manipulated keys, ignoring the items in the boat that were not fastened down; the stern went up, the bow down, until its long axis was vertical. Gingerly he eased the craft toward his friend, trying to keep its central axis over the hole. Again the change in wind caused by the ship ruined his good intentions.

  As the nose of the vessel entered the nearly circular opening, it left a smaller and rapidly decreasing annular space for the emerging gas to use. Molly realized what was happening, since she could see the wind, but not in time.

  “Charley! Wait! Stop!” she screamed. The Kantrick obeyed, but the damage was done. The wind lifted another cloud of sand and dust, as well as Molly herself, partway up the slope. “I’m blowing away! The boat’s funneling the wind!” she called. It might have been better for her to keep quiet; if Charley had lowered enough to bring the hull against at least part of the hole’s rim, she would have had a good chance of catching some handhold.

  As it was, her friend hastily reversed the descent. The blast of local air dropped. So did Molly, nearly buried in falling sand and invisible in the dust anyway. She missed both boat and robot as she went over the edge.

  Of course, she thought as she finally realized she was falling, there’ll be a lot of sand where I hit, and in this gravity I needn’t worry. Still, I hope it’s not level ...

  Chapter Nine

  Of Course I’m Collecting It

  Even on Enigma, Molly’s fall wasn’t long enough for her to formulate any more thoughts, or for that matter to come out with any words. The passage feeding the “volcano’s” crater was not vertical; its slope was so small that she struck the bottom in a few seconds, and in a few more was able to bring herself to a halt. Irritated but still in control of her temper, she started to climb back toward the faint light she could still see.

  Then something pushed her gently but firmly in the opposite direction, knocking her off her feet again. She guessed that this must be the robot, but with practically no help either from her eyes or her semicircular canals she had trouble making either her feet or her hands steer her in the right direction. She was only partly on her feet when she was bowled over again in slow motion.

  This time she bounced gently twice, taking much longer to hit the ground the second time, and realized that the floor had become steeper. She eventually collected enough of her senses to use the hand lamp that was part of her armor’s equipment.

  By this time Charley’s frantic voice was clamoring for attention.

  “Molly! I can’t see you! There’s sand still flowing into the hole; are you buried? Can you tell if you’re moving? I don’t dare bring the boat down again until I know where you are!”

  “I’m not buried, and you needn’t worry about crushing me,” the Human answered as calmly as she could. “I’m down the hole, apparently. I can see no light but my own, I’m sliding and rolling down a bare rock slope, and I seem to be well ahead of the robot. I don’t think I can have come very far, but I don’t at the moment see how I’m going to get back. The boat will certainly never get in here, I can’t re-program the robot to carry me back downwind, and I don’t think I can climb back on my own; there isn’t enough traction. Any ideas?”

  “Just to do what you said if you got in trouble—head back for the others at top speed. Do the rest of you know what’s happened?”

  “It seems pretty clear,” said Joe. “Carol’s trouble, amplified, I gather. It would seem best to stay near or even on the robot if you can, Molly; at the moment I am still picking up its broadcast, though if this is what happened to the other one we must expect it to get far enough below the surface to lose the telemeter waves eventually.”

  “At the moment I can’t see it, and I think I’m going downhill faster than it does.”

  “We’ll have to hope that downhill is also upwind. Keep looking for it, and if you do see it, do your best to get hold of it. Charley’s ropes should be extremely useful. Charley, I assume you’re on your way back for us. I’ll check out the receiver I used for finding the other robots, and we’ll try to get back to your neighborhood in time to measure how far from the original entrance you may have traveled. It should be possible to make a long enough rope in the shop to let one of us follow you and help you climb back, regardless of traction and slope. Jenny, will you see about that?”

  The Nethneen’s calm efficiency slowed Molly’s heartbeat to something near normal, though no Human tumbling through darkness in near-free fall is ever likely to be completely at ease.

  A gradual realization that her fall had ceased helped even more to restore her equanimity. At least, she reflected, there was one good point to Enigma: the worst thing about a fall was not the sudden stop at the end. Both the light and her sense of touch, through her thin gloves, told her that she was on sand once more. The rock must have leveled, or even formed a hollow, where the blowing grains could collect. First things first, however; where was the robot?

  She twisted the lamp control to narrow beam and swept it back and forth in the direction from which she thought she must have come, widening the search angle more and more as she saw nothing and grew less and less sure of her own sense of direction. After several tense minutes, there was a gleam of light on metal nearly ninety degrees from where she had thought to find it. She nearly panicked again as it occurred to her that she might have been right and the robot was now passing her to one side, but she retained enough self-control not to leap toward it. Holding the light beam as steadily as she could, she finally decided that the cylinder was comin
g almost straight toward her and reported the fact to the others, receiving a variety of nonverbal sounds of relief in response.

  “You know,” Molly added, “if you folks get back soon enough, it might be worth trying to block that hole completely with the ship. If the wind stops, the robot will also, I suppose, and I won’t get any farther in.”

  “But don’t you want to find your ice?” asked Charley innocently. Molly, for once, found herself with no answer ready.

  “It may be worth trying.” Joe also ignored the Kantrick’s question. “That won’t start the machine back this way, though.”

  “But if it turns out that it’s not too far from the hole, you or Carol could come and fix the controls. You could go on down to the ice with me, or at least look for it for a reasonable time. Would either of you be willing?”

  “Of course, it’s planetary structure,” Carol remarked thoughtfully. “I don’t really suppose Joe wants to spend more time than he can help away from his map, but it certainly sounds like fun to me. We’ll see what things look like when we get there.”

  “But how…” began the Kantrick.

  " ’Scuse me a minute, Charley,” Molly cut in. “Sorry to interrupt, but the robot is getting close and I’m going to have to travel a little to be sure I’m in its path. With no horizon, I’m even less sure of up and down than usual, and walking is awkward. Remember I’m out of control when I’m off the ground, just as everyone but Joe is. Please let me concentrate for a minute.”

  “Please keep us informed.”

  It was Joe who uttered the words and Charley rather than Molly who was surprised at his doing so after her request. He must have good reason, she assumed, and started talking.

  “It’s about fifteen meters away, still traveling at its set pace. I think I’m right in front of it now, and it’s heading right at me. It’s back at its basic height above the ground, Joe; it must have decided it was past the eddy. Here it comes. I’m getting onto its field shaper—no, I think it will be easier to ride right on top. I see you put some tie-downs there, too, Charley, and I’ll use some of this rope—there. You can talk now. I’m safely aboard, and riding with the thing wherever it’s going.”

  “Can you see where?” asked Carol. “What sort of place are you in? Is it more of a tunnel or a real cave?”

  Molly swept her beam around. “Tunnel fits it better so far, though it’s a very big one—forty or fifty meters high and three times or more that width. I’m fairly close to one side.”

  “Is the robot following a straight path?” asked Joe.

  “I can’t be sure. It doesn’t leave any track even in the sand, of course, and we’re over plain rock again.”

  “Would it be convenient for you to drag a foot and leave an occasional mark, if you do cross any more sand, so that we—I—could get some idea of your actual track? I admit I should set up some larger-scale recording procedures here, but I may not have time to do that before the boat arrives and we have to come for you; and of course I am to blame for not thinking to do it beforehand, anyway.”

  “If any of us gets to the end of this operation without bumping our heads on something we’ve left undone, he or she will be very lonely,” replied Molly. “Sure, I’ll make tracks whenever I can, and look back at them for as long as the light allows. At the moment it doesn’t look promising; the floor is getting steeper again, and there doesn’t seem much chance of sand or anything else loose collecting on it. I’ll watch, though. I certainly don’t want to fall asleep.”

  “Better tie yourself on, just in case.”

  “Thanks, I’ve already done that, Charley. Do I really need to keep talking? There’s nothing new to see or to say for the time being, and so far at least you can keep track of the robot.”

  “All right, relax unless you really have something to say,” agreed Joe. “One of us will call you every few minutes to make sure nothing has taken you by surprise; please answer.”

  “Of course.”

  Nothing visible occurred before the party lifted off on its way back to the Molly-trap, as Carol was calling it, though more and more things were going on in the Human’s mind. She knew she was not traveling rapidly, but the passage never lost at least some downward slope; she was getting farther and farther below the surface. This was good in a way, as it was presumably bringing her closer and closer to the ice that she was still sure must be somewhere below; but as time went on, she began to think more and more often how nice it would be to have company in this vast expanse of darkness. Not just talking company, but touching company. Rovor, her husband, for first choice, or little Buzz, but they were parsecs away; and of course it didn’t have to be Human, Joe or Carol would have been quite acceptable, not merely because they could control the robot.

  “We’re well on the way.” It was Carol’s voice this time. “Joe is a little worried.”

  “I suppose the signal from the robot is getting lost,” Molly answered.

  “I’m afraid so,” said Joe himself. “I am doing everything I can with the sensitivity of the equipment on the boat, and I have already calculated as well as possible how far you are from the place where you fell.”

  “What’s your answer?”

  “About two kilometers.”

  “That’s reasonable, assuming it’s been a fairly straight line—which is something I wouldn’t have guaranteed. Have you any idea of the uncertainty?”

  “About the same, I’m afraid.”

  “Why? Electromagnetic timing is good to millimeters at planetary ranges.”

  “My fault again. I sacrificed resolving power for speed, and wanted only broad measures of the winds. It seemed likely that small local ripples would be more nuisance than help in working out planetary circulation.”

  Molly had to admit that he was probably right. “A two-kilo uncertainty still seems pretty big, though.”

  “It does to me, as well,” replied the Nethneen, “but inconsistencies in the measurements of the last hour or so force me to admit the figure.”

  For the first time, Mary Warrender Chmenici began to feel real worry about her own safety. Two minutes later the anxiety deepened.

  “Joe! All of you! There’s nothing around me!” she suddenly cried out.

  “You mean your light failed?” asked Charley. The prosaic question steadied her, and she actually checked by turning the beam on the robot under her.

  “You would think of something like that. The light seems to be all right, but there is no ground under the robot. It’s supposed to stay only a few centimeters up, Joe!”

  “Yes. Look in other directions than what you think is down.”

  “I can’t be wrong about that, unless the robot’s guidance system has quit. Upward—I think there is rock, but it’s too far to be sure. What has been ahead all along, nothing. Behind—that’s better. Rock. Only a hundred meters or so away, I think, though I don’t trust my depth perception at that range and there’s nothing to give me scale. I’m going down, slowly.”

  “You’ve entered a cavern at a point well above its floor, I’d say. The robot is going straight down, ignoring wind, just as it went straight up for the eddy. Can you guess how long it was after you actually entered this space before you noticed it? Was your light on?”

  “It was on, I assure you. I missed the floor right away and yelled within a split second.”

  “Good. Let us know when you get to the bottom, and we’ll be able to figure the depth; the descent rate is set.”

  For the first time in their acquaintance, Molly felt an urge to tie knots in Joe’s appendages; then she realized that he was probably not really indifferent to her feelings, but deliberately helping her to control them. She forced herself to slacken the death-grip she had taken on two of Charley’s improvised handholds. The robot wouldn’t fall, and if it did, there wasn’t much damage likely to result here, she reminded herself firmly. A cave could hardly be more than a few tens, or perhaps a few hundred, meters deep, without collapsing. Of course, wtih Eni
gma’s gravity, that figure might have to be refined upward, depending on how the cave might have formed. Lava bubble? Solution space? Carol’s question, really, and the little woman would need data. The question of getting herself back to the surface could be faced later; her armor was good. This was not an emergency, just an unexpected research incident.

  So far. She dismissed that codicil from her mind, emphatically.

  “All right. Nothing in sight yet below. Joe, this robot must be sensing ground distance. Can’t you tell how far we’re going to—well, fall?”

  “Yes, it does, and no, I can’t. I arranged no readout for that information. Given time, I suppose I could do so, but I did not foresee any such need.”

  “Carol, you should have ridden him harder; you could have used that sort of information.”

  “Next time,” replied the Shervah. “This one just counts as educational experience.” The sarcasm was again evident; Molly felt more and more confidence in her translator’s handling of Carol’s tones. She wished she were more certain of Joe’s.

  “Still nothing visible?” Charley’s voice cut into her thoughts. Molly leaned over the edge of the cylinder and directed her light downward.

  “Not sure. Very vague brightness; just a moment. It disappears when I turn the light out, so it must be real reflection.”

  “Anything horizontal?” asked Carol. “I can’t for the moment imagine what could happen on a planet like this to form a cavern.”

  “I couldn’t imagine what could form solid rock, either,” Molly replied. “We both have a touch of revision to do on our ideas. To answer your question, I can’t see anything at my own level in any direction, and the glow below doesn’t seem to be getting brighter with any speed. This place is pretty big.”

  “But you can guess what might be light-colored underneath!” remarked Charley.