Molly was tempted to express her annoyance at the lost time even more vehemently than Charley, but again found that she would rather not reveal such a feeling in Joe’s hearing. It had happened; there had been no way to foresee it, and there was nothing to be done about it now. Complaint, or even remark, was meaningless. Leave that sort of thing for Buzz, until he outgrew it.
She was getting sleepy, and the surrounding darkness, relieved only by her own light, was more and more oppressive. She had used most of the rope Charley had loaded on the robot to fasten herself securely; she would not fall off even if she did go to sleep. Now, however, she began to wonder whether that were wise. If Carol were really close on her trail, was it best for Molly herself to stay with her own machine so faithfully—perhaps beyond the reach of the Shervah’s kilometers of guideline? If she did fall asleep, she would be unable to report anything that might give warning of another branch in the trail; she might descend into another cavern as large as or larger than the first, with equally variable winds, without ever knowing it. She was certainly descending, much too fast for her own peace of mind when she thought of the length of Carol’s line.
If only this tireless, indifferent thing that was carrying her would stop! If only—
She smiled and then grinned broadly as an idea took shape. For a moment she thought of calling Joe, but he must be busy on the mapping machine by now; and even if that weren’t going to be needed for her own rescue, the Rimmore and Carol would be annoyed if work were delayed on it. No, there was no need for discourtesy yet; she could report in a few minutes. She remembered now what Joe had said about the pressure sensors on the robot—a point she had known herself during their construction, though she had forgotten it for the moment.
Her armor recycled everything chemical, of course, with negligible leakage; all it needed in any normal—or over ninety-nine percent of all abnormal—usage was replacement of energy. It had water and food buffers, some full and some empty at the start, to handle lack of uniformity in use versus production of these. In other words, she had spare water.
She could get at the spare water. The processing units of the armor were around her midsection, making her feel at times, where freedom of motion was concerned, a little as she had in the weeks before Buzz had been born. There was no risk of mistake, deadly as the environment around her was; she could have taken the armor apart and reassembled it blindfolded—Humans sometimes retired to Earth, but they grew up in other environments; and a Human who did not know armor was simply not adult. One was expected to design and build one’s own.
The fact that she could open it without looking did not mean that she did. Carefully she unsealed a panel near her left hip, closed four valves, and removed a flexible container that held rather less than a liter of water. Two of the valves were on the container itself, the other two on the other side of the breaks with the armor tubing. Now, carefully, she reopened one of the former, and with gentle pressure began to squirt a fine stream of liquid over the front surface of the robot.
The metal was some forty degrees below water’s freezing point, and a film of ice quickly formed over its surface. Well before the task was complete, Molly could tell her plan was working; the robot’s direction of travel began to veer to one side. Using the brook as her direction guide, she covered the cylinder until the machine was moving back in the direction from which it had come.
She thought briefly of coating its entire surface and waiting where she was for Carol, but decided against it for several reasons.
One was economy of water. Another was the robot’s computer; it was, as Joe had said, ready to allow for and discount plugged pressure ports. If she covered most of the surface with ice, she might miss a few tiny areas and find the machine moving in some unpredictable direction while she wasted even more water trying to find and block a single microscopic opening.
“I’m heading back toward you, Carol,” she reported briefly. The response from three incomprehensibly mixed voices was completely satisfying. Carol, Jenny, and Joe all produced variations of “What did you do?” and “How did you do it?” Charley said nothing on the general channel; his voice came through on private. “I wondered when it would be. Are you sure the rope will still reach?”
The Human described her technique briefly, not trying to comment on Charley’s words.
“None of us can feel too guilty for not coming up with that one,” commented Jenny. “Who would have water in her armor?”
“I’m not bragging,” assured Molly. “I should have gotten the notion long ago. Now, if you’ll forgive, I intend to stop observing for a while. I’m not sure I can really sleep on top of this thing, but I’m going to try.”
“Are you sure that’s wise?” asked Charley.
“No, I’m not at all sure; but it’s going to have to happen some time soon, and I feel safer right now than I have for some time past. I won’t turn the light out, and if anything really out of the way happens, the chances are I’ll notice—I hope. Right now, sleep is my prime order of business—unless I spot some life forms, of course, Carol and Jenny.”
Joe, in the shop working on the new mapping robot, said nothing, and none of the others was in sight of him. If they had been, they would probably have been unable to guess his concern. Even Charley, who resembled him fairly closely in the eyes of the other three, was of a widely different body chemistry, physical engineering, and evolution, and would not have noticed or interpreted the suddenly increased effort the Nethneen put into his work as Molly finished talking.
Joe might have been worried, but Carol, presumably in far more danger at the moment, was not. She rode the rim of her robot, holding on with one hand and grasping a collecting can in the other. Like Molly, she had clipped her light to her helmet for convenience; unlike the two males, she could turn her head, though her eye arrangement made this unnecessary. She was noticing only incidentally where she was going; like her Human friend, she could not feel the wind that was guiding the robot. She was, of course, hoping for more life forms; in spite of Joe’s emphatic denial of the possibility and her own knowledge that Enigma could not be a million years old and should not have evolved anything like the things she had collected, she knew what she had seen and had little doubt of its nature. A really close examination might prove her wrong, of course; she was burning to get the material back to the instruments in the bout and the tent, and the even more sophisticated equipment on Classroom, but she could postpone that while there was a chance of getting more data on Enigma. Her work, as initially planned, bridged that of Jenny and Molly; she was interested in the planet itself, physically, structurally, chemically, and biologically. She had not really expected the last aspect to appear, but since it seemed to have done so ...
Carol’s emotions were less obvious than Charley’s, but she had them.
She had found a stream, presumably the one that Molly had reported, and confirmed its composition with some of the safety equipment on her armor; it was not pure enough for her to drink, being loaded with dissolved salts, but it was ammonia. The robot was following fairly close to it, as Molly’s had done. The Human, when last heard from, had been following it back up, and it seemed likely that they would meet soon. Carol wondered in passing what Joe’s program would do with two robots in collision, but she didn’t waste any real time worrying about the matter. If anything of the sort seemed imminent, she could steer her own machine out of the way.
The only thing that caused her anything like worry was the rope. She had made no effort to go back to her first landing point in the cave and lay a straight line to the new passage, so about a kilometer of it had been wasted by the supposed wind change. There was not very much left in the coil now, and she had not considered what to do if it ran out before she met her friend. She found herself keeping one eye more and more constantly on what was left, and as this dwindled to a few hundred meters she slipped one of her tiny, almost human hands into the control access opening in the body of the robot.