“That seems reasonable,” admitted Molly.
“In that case,” Carol pointed out promptly, “we might as well stay right here, as we wanted to do awhile earlier, and let them catch up with us.”
“Two minor objections,” replied her big friend. “They might not encounter the same river, and there should be more of this ecology to be seen as we keep going.” Carol was silent but made a hand gesture of agreement. Molly, too, forbore to pursue the subject further; she did not want to admit how much more the first of the two points now meant to her. Not, at least, in Joe’s hearing, and of course it would be going out of her way to shift to private channel just to make the remark to Carol.
The Nethneen’s voice sounded on top of her thought of him.
“Molly, I don’t suppose your robot’s power is on yet. About how much time do you two have left in your batteries?”
“I’m about eighty hours,” Molly replied promptly—she had no need to look at her gauges for that information. “Carol’s batteries carry more energy, but her size gives her a poorer surface-to-volume ratio than mine, and she must have had to use more on temperature control. How about it, Carrie?”
The smaller woman had no need to look, either.
“About ten hours less than you. I’m taking it easy on eating until we can charge up again.”
The Nethneen spoke thoughtfully. “It might be a good idea for me to join the underground mapping. It won’t take long to finish another machine; I started the parts on automatic down in the shop as soon as I finished the radars for Charley and Jenny.”
“You mean you aren’t back at your map yet?” Molly asked with mock severity.
“I have just reached the tent for a quick look—I suppose the data might be useful, even in the present emergency ...” His voice trailed off; none of the others could even guess what he was thinking.
“For Pete’s sake—if that doesn’t translate, never mind—get into the tent and look your own work over.” Molly was not entirely mocking. “We’ve been guided by air currents most of the time since we’ve gone underground. We haven’t the faintest idea what the rules about wind are on this silly world, except that there’s something peculiar about them—Jenny found out before we got here that the high ones were circulating toward the summer pole, which I at least would expect the surface currents to be doing instead. Stay there for a few hours and see if you can figure out enough of the pattern to make a real guide for us. Rivers have their good points, but this one seems to be taking us toward the middle of the planet, and there’s a limit to how far I want to go in that direction. Get to your map and think!”
The Human caught her breath and blushed; she hadn’t meant to get so intense, and just what Joe did probably wouldn’t make that much difference. Maybe nothing would. Was she, Mary Warrender Chmenici, getting panicky? Thoughts of Rovor, and Buzz, and planets where one could walk around without armor, and even swim or sleep outdoors, went flashing through her mind; she suppressed them sternly. Reality right now was Enigma.
“All right, Molly.” Joe’s voice was as quiet as ever; she couldn’t tell how much he had read of her feelings. “I’ll let you know how the map is doing; you can help in the analysis, perhaps. I’ll be in the tent in a few seconds, but will no doubt be longer working up a meaningful description for you.”
Carol looked at her huge friend curiously, but decided to say nothing. No doubt the Human would explain the thought behind her outburst in good time. The Shervah, with a real research problem holding her attention, was genuinely unable to get her mind onto the fact that she was in actual physical danger—though the suggestion that her mind was at all similar to Charley’s would have been taken as a serious insult.
Molly, more aware of the danger than of anything else but quite ashamed of the fact, deliberately turned her attention to the robot. Carol might not have been serious when she suggested that the heat from the Human’s armor might help dry the machine out, but the point seemed well taken anyway. She was beginning to wish that her heat pump exhausted almost anywhere except between her shoulders; she had used it so often as a tool lately that the problem of aiming its microwave beam was becoming a major nuisance. She seated herself, most uncomfortably, on the field disc of the robot in front of its control access port and bent forward as sharply as the armor itself permitted. She was reminded emphatically of a lab exercise she had had to do in crystallography, involving some hours of looking into a microgoniometer, the week before Buzz’ birth. She couldn’t see whether she was really throwing heat into the open port; she wasn’t contortionist enough to see the port itself, or enough of a cold-worlder to detect the beam with her own senses. She comforted herself with the thought that the radiation had to be striking some part of the machine and producing at least a little effect.
“Carol,” she remarked, very carefully on private channel, “I’ve just thought of another attachment for the next robot design. They should have internal heaters to dry them out automatically.”
“I don’t think even Charley would have suggested that seriously,” the Shervah replied.
“I certainly hope not. You know, little friend, your suit must be refrigerating much more enthusiastically than mine at this point; the environment is really hot for you. Wouldn’t you do as much, or more, good than I here—quite aside from the fact that you’d fit better?”
“Maybe. Let me finish checking out this stuff here, and I’ll spell you.”
Molly forbore to ask how long the checking out might take and settled herself for an indefinite wait. She never knew how long she sat there, but was not too surprised that it was not Carol who brought the session to an end.
“Molly, I have a problem.” It was Joe’s voice, calm as ever.
“With your map? Isn’t it growing properly?”
“Very nicely, but very unexpectedly. Your remark that winds aloft were traveling from winter to summer pole, and that this surprised you, was what I checked first; the upperlevel robots seem to be agreeing with you. Naturally I assumed that the surface circulation would be in the opposite direction, but the lower-level machines don’t agree. Except for minor deflection one would expect from inertial effects—the rotation is slow, but Enigma does rotate—the air at all levels is going from winter to summer hemisphere.”
“Then the return circulation must be underground—that must be the wind pattern we need for guidance!”
“No, Molly. Think. The air is coming out of every cave in your area that you, or Charley, or Jenny have found—there was even some coming up through the sand where Carol was trapped, and that was all in the summer hemisphere. Where does it come from?”
“And where does it go? You need a sink as well as a source!”
“Precisely. I think I have an answer to the sink, but not to the source question—or rather, I think that Jenny provided us with the sink answer.”
“How?” grated the chemist. Molly simply waited for an answer. She was not surprised that Joe had one; he would probably not have mentioned the question until he did.