“I’ve thought of a way to narrow the search,” Molly put in rather diffidently.
“How?” Again several voices sounded together.
“It would mean interrupting part of your mapping project. You could start another robot at the same place the first one was and watch to see where it went.”
“We don’t know that the air currents haven’t changed. It’s been hours now, and that storm that blew me away when we first landed certainly wasn’t permanent.”
“I realize that. I still think it’s worth trying. Even if the second robot doesn’t go to the same place, it will be investigating currents in the area where the first vanished; and that would seem to me to be worth doing in any case.”
“It would mean staying here, away from the tent and the main work.”
“Not for all of us. We could take turns—or just one of us budget a few hours, since that’s all it took the first one to vanish. You could stay at the tent and watch your map grow—maybe other information would appear there that would help—and Jenny of course must get back to her chemistry; but Charley or I could stay here for a while, and Carol might enjoy it—except she might forget to watch the robot if the landscape got too interesting.”
“Wouldn’t that interfere with your work?” asked Joe.
“I don’t think so. Much of my thinking is going to depend on what Jenny’s analyses tell me. I’m sort of hung up until I can either find ice or get some evidence that it’s just not here. Charley has been working along with me, unless that new idea that he won’t describe is a branch-off. I’ll be glad to ride herd on a robot for a few hours. Which one do you think would be best to pull out of your pattern?”
A little more than three hours later, the boat settled back to the ground at the starting site of the lost machine. Joe, after some vacillation, had decided which of the robots to pull from his pattern, and the group had collected it and its slaves. This had taken most of the time, as the slaves were by now scattered over a fairly large area.
The device was placed precisely where its predecessor had been, Carol’s memory serving as the final check, and Joe made sure that the original programming was still set up. None of them could be sure whether the local wind was just as it had been before; Carol had not been outside to feel it. Since no one had been present when the first one had started to move, only the original instrument log could have been used as a check; and, as Charley remarked—no one else bothered to—if that had been to a large enough scale, the present reenactment would not have been necessary anyway.
Possibly.
“All right, it’s ready,” said Molly as Joe closed the access plate of the metal cylinder and stepped away. “Charley, you take the others back to the tent and then come back to keep an eye on me. It shouldn’t take you very long, maybe three quarters of an hour. It was much longer than that before we lost track of the other one, so there’s no need to worry about me. My batteries are charged, emergency chemical cells loaded—I’d be all right for days if I had to. Don’t worry, just get the others back to their work.”
Charley, rather to her surprise, made no objection, and she watched the two-hundred-meter torpedo lift from the rock and vanish into the bright dust clouds.
She did not keep her eyes fixed on the robot, though she watched with some interest as the slaves detached themselves from its top and drifted upward. She knew the master would not start its motion until they had all reached their planned altitudes, so she spent some minutes looking over the ground in the hope of finding some evidence of the ice he so badly needed for her theory—no, she corrected herself, her hypothesis; at the present rate she would have to be very lucky for it to graduate to theory status.
Still, there had to be ice somewhere; the surface material Jenny had analyzed up to this point was far above Enigma’s average density. More and more it seemed likely that the stuff was inside; that Enigma, like a middle-aged comet, had lost much of its outer ice and concentrated the silicate to a real crust. If all the surface had been sand, or salt, or dust, this would be easy to believe; but rock? She found an exposed patch of the dark, hard stuff and examined it as closely as she could by eye. She had ordinary tools, and chipped off a few more pieces with laser and hammer; but there was nothing about them, or the flare as they vaporized under the laser beam, to suggest that these were any different from the earlier ones. Sodium, of course, as any human eye could tell, but that ubiquitous element was not very informative.
She glanced up at the robot. It had started to move, so she suspended her planetological research for the moment. The metal cylinder drifted along, into the wind as planned, its base a few centimeters from the ground, much more slowly than a comfortable walk. She amused herself by marking its path with her own footprints whenever it passed over anything soft enough, and by the time Charley came back with the boat she had decided that the wind was fairly steady. While she could locate the foggily visible sun at times—the combination of filters and eyeshades that even she had to use to protect skin and eyesight from the tiny, blazing disc had startled her friends considerably—she was at a latitude where it was above the horizon all day and was in no position to judge absolute direction.
The situation was getting rather boring by the time the boat settled down near her again. She was, for once, as glad to see Charley as he was presumably relieved to see her.
“Let’s establish some direction around here!” was her greeting. “Will you get the inertial system to line up the boat’s long axis with the local meridian? I feel lost not knowing which way is north.”
“No problem,” replied the Kantrick. “Are you sure you’ll feel any less lost when you do, though? You don’t know what there may be in any direction, whether the latter is named or not.”
“Maybe not, but I’d feel happier knowing whether I’m walking azimuth twenty or three hundred twenty. I admit it would also be nicer to know where I’ve been—well, I do; I was at Joe’s Station Fifteen—and where I’m going, but knowing which way is some help. Don’t be so individual, Charley. Haven’t you ever tackled an idle problem when you were bored?”
“I prefer to find an important one. However ...” The craft lifted, swung slowly, and settled once more. “To within a grad or so, the axis is pointing along a great circle through the planet’s poles of rotation, with the bow toward the nearer one.”
“Good. Thanks. By my convention, that’s north—it’s northern hemisphere summer. The robot is drifting toward azimuth sixty-five or so, not that my line of footprints is very precise. What can we do now to keep busy? It didn’t occur to me that this job would be simple snail-watching. If this thing is going to disappear, I wish it would get about it.”
Charley was of course able to infer something about snails from the context, but giving him more details killed a little time. Molly was rather amused at part of his reaction; he was not quite sure whether to add the words in question to his translator’s vocabulary, vast as the memory capacity of the equipment was. He wasn’t convinced that they were worth the space. The Human had calculated long before that she could add words as fast as she was likely to be able to talk for the rest of her life without reaching the storage limit of the fifty or so cubic centimeters of doped synthetic diamond at her throat. This was one reason she had deliberately made the attempt to program the device to handle tone inflections—or whatever Nethneen, Rimmore, and the other team members used instead of tones—as well as formal symbols.
She spent some time at this now, chatting idly with Charley, trying to read likely emotions into his answers and assigning different tonal values to them. She had no real confidence in the result, but it was fun.