“Keep your light and at least one eye on that stuff, please. In this gravity I can’t help feeling it may blow away, and some of this mud seems soft enough to lose small pieces in. It all seems pretty wet, too; you’d think in this wind we’d find a dry surface occasionally.”
“We didn’t have the ammonia drying, up at that level.”
“True. Our reflux unit doesn’t get very far below saturation, does it?”
Molly sat down again with air recycler beside her, mask still on her face and the connecting tubing carefully laid out to avoid tangles. The most important part of the suit was still to be removed.
This was the “blubber,” the skin-tight layer some four millimeters thick in most places that covered her entire body except face and hands and contained the lining that absorbed perspiration and body wastes and the capillary system that pumped it to the actual recycling machinery. None of this contained moving parts larger than molecules, and in theory should last for years of use and even abuse; but Molly peeled it off with the utmost care and spread it out beside the rest of the armor.
Then she entered the water and luxuriated for ten minutes. She climaxed the operation by holding her breath, removing the mask, and submerging completely for several seconds, rubbing the dried remains of sweat and, she admitted to herself, occasional tears from her cheeks. She stood up, accepted the mask handed to her by the Shervah, pressed it against her face, squeezed the tubing, and blew it clear around the edges; then she resumed normal breathing, only slightly afraid that she would detect the scent of ammonia.
She didn’t. There was something else, very faint, that she failed to identify, but it did not worry her. The water could not be expected to be absolutely pure. She picked up the inner suit and immersed it in the pool, scrubbing its outer and especially its inner surfaces carefully and as completely as possible with her hands. Then, not worrying about drying—the suit would take care of that when repowered—she redonned the equipment, and presently stood fully accoutered in front of her small companion.
“That was worth it. I’ve never wanted a bath so much in my life.”
“I can sympathize, but I think you were perfectly insane, just the same” was the response.
“Certainly I was, but that remark from someone who can pay more attention to a bunch of weeds than to the fact that her batteries are running down and the charger is out of action…”
Joe interrupted again. His exact words were not important, but they served to change the subject. Molly wondered if he ever felt any real emotion; it was possible that the embarrassment he occasionally seemed to show was just to keep his listeners from feeling inferior. She was soon to form a more definite opinion.
The journey was resumed, and they had been on the way for perhaps another two hours when the Nethneen’s voice came through again.
“My computer seems to have failed.”
“You have a backup, don’t you?” asked Charley.
“Certainly, but it is behaving similarly. The diagram being relayed back is quite impossible.”
“As impossible as the life on this planet?” asked Carol, perhaps too pointedly.
“At least. The model has just plotted a cavern nearly spherical in shape and approximately twelve hundred seventy-four kilometers in diameter.”
“That’s ridiculous, but not impossible.”
“You’ve been computing, too, Charley?”
The Kantrick evaded the question by ignoring it.
“The biggest I’ve encountered so far was less than twenty, I admit, but even that means this gravity just doesn’t count. We’ve known that all along. What’s your record?”
“So far, just over thirty-five in greatest dimension; it was not very spherical.”
“Your lead mapper probably has something wrong with its radar. Wait until some others reach the same point. What does your program do when two of them disagree with each other?”
“Checks against a third or a fourth, if necessary.”
“Then wait a few minutes. The others will reach the same point, or points farther on, and straighten things out.”
Joe made no answer, and everyone waited, except possibly Jenny, who might have been too absorbed in work to hear. After about ten minutes, Charley made himself heard again.
“Have any more mappers reached the area?”
“I would assume so. There is no easy way to check their location except by the model sections they have completed. There has been no change in the model.”
“Then either a lot of your mappers have the same fault, or you’ve lost a lot of mappers. What could happen to them? What would rivers like the ones we’ve been meeting do to them?”
“Nothing, as far as I can judge.”
“But there’s no way you can identify individual signals.”
“No. It could have been done, and I thought of it, but the arrangements would have been complex and time consuming. I was worried about Carol and Molly and wanted the devices ready quickly.”
“There is one possibility Charley didn’t mention,” Carol cut in.
“What is that?” asked Joe.
“That there really is a twelve hundred-kilometer cave below you. No one has really calculated the strength of this rock. We know the gravity is weak and the planet young. It may have started as an ice body, a sort of giant comet nucleus, and accreted silicates later.”
“And more comets,” added Molly. “Consider the other caves. That would make the center just a super-kame.”
“But how could such objects accrete without at least melting at the time?” Joe was more than doubtful; this was a worse blow than the life discovery.
“I don’t know offhand; there’s a lot of information to be collected before we do much calculating, let alone genuine theorizing: The first job would seem to be getting that machine you’re riding down to where your model says the big cave is and checking for yourself whether it’s really there. Maybe, if it is, we can get together more quickly than any of us were expecting. I certainly hope so. Have you met any rivers yet?”
“No. I don’t expect any. The air going in from the surface would be warmed both by compression and from the surrounding rock. If any liquid were filtering down, I would expect it to vaporize long before reaching my present depth.”
“I hope you’re right. That’s a very firm conclusion, and another mistake would be quite a jolt, wouldn’t it?”
“Yes, Carol. Facts can be most tactless at times. However, I am learning to put up with them—perhaps a little late in life. I am following what seems the best path that my model shows to the central hollow.”
“Central?” asked Molly.
“If real, yes. It commences eight hundred thirty-six kilometers below the surface and has a radius of six hundred thirty-seven. The planet, by our earlier measures, has a radius of fourteen hundred seventy-three. Unless the cavern is off-center on one of the axes at right angles to the rotation one, it is a hollow center to the planet.”
“I don’t really believe in hollow planets,” Molly said thoughtfully.
“Neither do I, yet,” replied Joe with what had to be genuine emotion, Molly was sure. “Suspend your judgment, young woman. I am trying to do the same. I am glad this machine can follow the indicated passage automatically; I am not sure I am in a state to guide it properly myself.”
“How deep are you now?”
“Six hundred fifteen kilometers from my entry point.”
“Two hundred twenty-one to go.”