“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 Enigma’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.
“As long as we call it a guess, sure. Just let’s not say it until I get there,” replied his Human friend. Molly was learning caution.
“Is the glow uniform, or can you make out features?” asked Carol.
“It’s still hard to be sure, but there seem to be lighter and darker patches when my light beam is fairly wide. When I narrow it down and sweep it around, it’s harder to compare.”
“Keep watching with the wider beam, and let us know when you feel sure the features are increasing in size. That will tell us you’re near the bottom, whatever the bottom is,” Joe pointed out.
“All right. I rather hope there’s no wind down there; I’m starting to feel cramped on this thing. It would be nice to take a walk.”
“There’s good reason to hope the wind will be straight up from whatever you land on, isn’t there?” came Charley’s voice.
“There’s hope. I’m not going to claim good reason.” Molly did not feel like mentioning the word ice for the time being; she was still on the emotional backswing from the jump at a conclusion that had carried her into her present trouble. If Charley wanted to keep his optimism, all right.
There were features below, spreading and growing more distinct as she approached. Nothing really clear yet; just some places a little darker—really darker, or a little deeper?—than others. Her mind came back to full concentration on business, and she reported tersely to the others as the picture clarified.
“It’s not a level bottom. I thought for a minute the dark places must be deeper—farther from the light—but it’s the other way. One of them is higher than I am now…”
“Which way?”
“That way. Please, Charley; what possible direction reference do I have? Even if this cylinder hasn’t turned during descent, and I’m willing to believe it hasn’t, I have, often enough to forget which way I was originally facing. The lighter stuff is coming up now, and I’m going to meet what seems to be a steep slope close to a fairly sharp boundary between light and dark. There. Descent has stopped, Joe. How far down did I go? At least roughly, in kilometers.”
“About six hundred fifty meters.” Still no detectable emotion, but the Nethneen had to be laughing; Molly herself was. “Are you moving at all? Is there still wind?”
“Yes, apparently. I can’t feel it through armor, and I don’t plan to step off as long as this thing is traveling, but it is traveling, so I assume it senses impact pressure.”
“What’s the ground like?” cut in Jenny. “Any visible difference from what we’ve already analyzed?”
Molly swung her light downward and looked carefully for the first time, and a grin spread on her freckled face. “I can’t see the ground, Jen,” she said softly. “It’s covered with feathery, silvery-looking crystals.”
“What?” Carol almost screamed.
“Yes, dear. I…”
“Get some! Are they really dense, like an actual metal, or could they be conducting hydrocarbon—the stuff Jenny mentioned earlier?”
“I can’t tell the density, for several reasons. Even if there were decent gravity, I have no way of telling how loose or open the structure of this fluffy stuff may be; even its inertia won’t tell me anything. It’s bound to be low. Maybe if I’m here long enough I can tell you whether it’s growing or not, but I rather hope to get specimens back to you for that sort of check.”
“What are the temperature and pressure? Not much different from the surface, I’d suppose.”
Molly consulted the environment checkers on her armor. “No significant pressure difference—in this gravity and with this gas mixture that would take several kilometers change in altitude, I’d think. The temperature may be a trace higher; unfortunately I didn’t think to record it to a hundredth of a Kelvin before I started down. It’s a hair over two thirty-five. For practical purposes, you have surface conditions here except for light.”
“And that difference would be in favor of life!” said Carol happily.