“I don’t see anything very different about them, she admitted at last. She was embarrassed again; if Joe had spotted a difference, surely there must be one. What could be expected to show this quickly? The region was presumably getting more heat, of course—potentially higher winds, but if anything the patterns of radiating lines were smaller suggesting slower air currents. It couldn’t be that.
“See the wind strength?” Carol still sounded sarcastic. Would Joe be drawing conclusions already about general circulation? It was a temptation common to Human minds—she wasn’t sure about many of the other species—to notice things that supported one’s one preconceived ideas. Surely Joe was above that, though; or was he: Did the robots measure vertical components? She tried to remember.
Then she suddenly saw the larger pattern. “Oh! Of course! What can have happened? When did it happen?”
“I only noticed it a few minutes ago,” replied Joe. “I’ve had to take some readings from other sensors on the slaves to make sure, but the air is generally rising over that area, and…”
“But I meant the other thing—the missing robot!” exclaimed Molly. “Isn’t that what you were talking about?”
“Oh, no. That couldn’t happen. Of course they’re all…” Joe fell silent as he realized that Molly was quite right.
Chapter Eight
Of Course, It’ll Be Soft
The boat hovered a hundred meters above Enigma’s surface, with all five occupants staring intently into their screens. It was daylight, though dim, even by Molly’s standards, since they were close to the summer pole, and all were using the light that most nearly suited their own eyes. Meter by square meter they were searching the landscape for the missing robot.
The surface was different here. Rock and sand were interspersed, as they had been elsewhere, but crater-topped cones were scattered freely; they had seen dozens in the last two or three hundred kilometers as they approached the final recorded position of the lost machine, and five were visible from where they now hung. Nobody wanted to believe in active vulcanism on a planet this small and young, but nobody could think of another name, or another explanation, for the cones.
And nobody could see the glint of metal against the sand or the rock. Joe, dividing his attention between his visual screen and receivers set for the robot’s telemetry broadcast, had had nothing to report, either. Jenny had put her chemical work aside and was searching as earnestly as Molly, but neither had seen anything worthy of comment. Carol was very interested in the local topography and might conceivably have been paying more attention to the hills than to possible metal cylinders, but she was tactful enough not to make irrelevant comments. Charley was the least restrained, as usual.
“Joe, have you picked up anything from the slaves of the missing unit?” he asked after many minutes of futile circling.
“I haven’t tried. They were on a different frequency and were transmitting to the master to be relayed from it. Naturally, we lost touch with them when it went out.”
“But if they are anywhere around broadcasting, couldn’t we pick them up directly?”
“We should be able to. I’ll try it.” The Nethneen operated his keys briefly, and his voice showed emotion that might have been enthusiasm or might have been annoyance—Molly could have sympathized with the latter. Why did Charley have to be right? “Yes. They’re radiating—all five of them.”
“Where are they?” came several voices at once.
“That will take some work. The original setup was designed to locate them relative to the master. We may have to get directions and go back to crude triangulation ...” Joe fell silent and his tendrils worked keys again.
“What were their heights?” asked Molly from the boat controls. “I’ll get us level, or nearly level, with each of them in turn, and we can home in on it if you can get direction.” She sent the craft floating upward as she waited for Joe’s reply, knowing that the lowest of the slaves was at five or six kilometers. She also set up an outside pressure reading for her own screen, remembering that the things had been set for pressure rather than absolute altitudes.
Twenty minutes located all five of the devices, since Joe elected not to bother to bring them aboard. Horizontally, they were all within about fifteen kilometers of the spot where the master robot had last indicated its position, and very much closer than that to each other. There was still no sign of it in that neighborhood, however, and no obvious place where it could have been hidden. Enigma showed no evidence of tectonic activity hereabout unless the “volcanoes” counted; there were no canyons, caves, or cliffs with landslide evidence—or without, for that matter. There were no lakes within ten kilometers, and the few that lay within twice that distance seemed at casual inspection to be shallow, though this might have to be checked. There were no biological hiding places like forests.
“Will radar get through ammonia far enough to check those lakes, or will we have to do each one personally?” queried Joe.
“Depends on their depth,” replied Carol. “It won’t go very deep. The ammonia must have electrolytes in it—right, Jenny?—and will be a fairly good conductor. We’ll try. Who’s densest?”
“I’m made of water,” replied Molly, “and we can add enough weight to my armor to let me submerge. I can almost certainly see farther than any of you through the stuff, with my short-wave eyes. That would let me do a search most quickly.”
“That is all true,” replied Joe, “but any of the rest of us, except perhaps Carol, would be safer. Jenny’s done it so far, with no trouble. The ammonia is, for us, at a relatively comfortable temperature. While your armor should keep you alive, if anything should go wrong with it you would be in far more danger than one of us. I suggest that Jenny and I search the lakes, weighting our armor as she did before; I because it is my problem, and Jenny because she would be able to observe and sample the lake bottoms, in connection with her own work, at the same time.”
The Rimmore grated strong approval, and no one else objected. Four hours later Jenny was happily burdened with bottom samples from every lake within twenty kilometers—some of them had been over fifty meters deep—and Joe’s tendrils were empty.
The raspy voice was more enthusiastic than Molly had ever heard its owner before. “Look at this stuff! Clay minerals—a real likelihood of protolife compounds on their surfaces! I was hoping for a chance to do some structures. A lot of this sparkly stuff—it must really catch your eyes, Molly—you know, I have some ideas about that. It could be prelife stuff, too; remember the Dendender, and the Pahrveng, and—oh, at least a dozen others you sometimes meet at the School. They all look metallic, but its really carbon compounds with free electron channels in their structures that make them shiny and gives them real electric conductivity in their nervous systems. Some of them can handle this temperature range. I’ll have to get at that stuff I thought was free metal. And look at this slime! Beautiful! Docs somebody want to look it over with a simple microscope—I’ll bet it won’t take chemistry to tell the story here!”
“But who walked off with Joe’s robot?” asked Charley. “You mean what happened to it?” “Of course.”
“I don’t know. If it’s in any of those lakes, it’s sunk into the mud. It was dense enough for that, wasn’t it, Joe?”
“Yes, in principle. I don’t know how long it would take in this gravity. I’ll have to rig up some sort of metal detector and look for it under the mud, I suppose.”