“Molly! What are you up to?” cried Charley.
“I’m getting a look at that hole in the ground, and I’m getting gas samples out of it?” she replied firmly. “Besides, if the robot tries to go out of sight, shouldn’t we stop it?”
“How?” came the pointed query in at least two voices. The Human thought as quickly as she could.
“If I block its pressure sensors except on one side, won’t it suppose that way is upwind?”
“No,” replied Joe. “The actual sensors are inside, fed by microscopic openings in the shell. You couldn’t block them all without wrapping the whole machine in something. You probably can’t even see them. If a few are totally blocked, the controller will assume that that’s what’s happened and omit them accordingly from the wind calculation. How do you suppose Carol and I were able to ride one awhile ago, without upsetting its guidance?”
“Get off while you’re still on the outer slope?” cried Charley. “We can figure out how to follow the machines later, if we decide it’s worth the risk.”
“Wait till I get to the top,” retorted Molly firmly. “At least I’m going to get a look at that hole. Bring the boat down so I can reach some of the climbing grips on the hull; that will be better than rolling back down the hillside and maybe getting buried in the sand.”
Again Charley made no vocal objection. The boat was now almost over the center of the crater. He lowered it until the bow entrance port was about level with the rim of the cone and worked his way slowly toward the point where his friend should appear over the edge in a few seconds.
He judged the position properly, unfortunately. Suit and cylinder appeared directly in front of him. At almost the same moment, the wind from below, deflected by the hull, raised another puff of blinding dust; the Kantrick was using long-wave pickup for his screen, but not long enough. Both he and the Human were cut off from view of each other. Simultaneously the robot swerved, in response to the change of wind, in the direction in which Molly had stepped to avoid its path. Its push was gentle—too gentle to feel at first, or in time. Joe would probably have realized he was falling soon enough to react properly; the Human, already at only a fifteenth of her normal weight, did not. By the time either she or Charley could see clearly, she was sliding down the inner sand slope, well ahead of the robot.
The latter was following, and she made every effort to scramble up toward it, or at least to slow her descent enough to let it catch up. Charley moved the boat ahead of them and tried to lower it so as to block the paths of both, but the craft was too big. Its stern, two hundred meters away, encountered the far side of the pit and caused an unplanned dip at the bow end; Charley frantically manipulated keys to level off, forgetting for a moment that there was no absolute need to be level and that he could have blocked the hole at the bottom with the vessel’s bow. By the time this occurred to him, Molly was out of sight of his screen, and he did not dare lower for fear of crushing her with the hull until he could find her again. This took perhaps half a minute.
She was now at the very bottom of the slope, apparently standing on something solid, with sand that she had displaced still pouring past her feet and vanishing below and the wind from the crater now marked by another rising plume of fine dust. The robot was half a dozen meters up the slope, descending straight toward her in its unhurried fashion.
Charley manipulated keys, ignoring the items in the boat that were not fastened down; the stern went up, the bow down, until its long axis was vertical. Gingerly he eased the craft toward his friend, trying to keep its central axis over the hole. Again the change in wind caused by the ship ruined his good intentions.
As the nose of the vessel entered the nearly circular opening, it left a smaller and rapidly decreasing annular space for the emerging gas to use. Molly realized what was happening, since she could see the wind, but not in time.
“Charley! Wait! Stop!” she screamed. The Kantrick obeyed, but the damage was done. The wind lifted another cloud of sand and dust, as well as Molly herself, partway up the slope. “I’m blowing away! The boat’s funneling the wind!” she called. It might have been better for her to keep quiet; if Charley had lowered enough to bring the hull against at least part of the hole’s rim, she would have had a good chance of catching some handhold.
As it was, her friend hastily reversed the descent. The blast of local air dropped. So did Molly, nearly buried in falling sand and invisible in the dust anyway. She missed both boat and robot as she went over the edge.
Of course, she thought as she finally realized she was falling, there’ll be a lot of sand where I hit, and in this gravity I needn’t worry. Still, I hope it’s not level ...
Chapter Nine
Of Course I’m Collecting It
Even on Enigma, Molly’s fall wasn’t long enough for her to formulate any more thoughts, or for that matter to come out with any words. The passage feeding the “volcano’s” crater was not vertical; its slope was so small that she struck the bottom in a few seconds, and in a few more was able to bring herself to a halt. Irritated but still in control of her temper, she started to climb back toward the faint light she could still see.
Then something pushed her gently but firmly in the opposite direction, knocking her off her feet again. She guessed that this must be the robot, but with practically no help either from her eyes or her semicircular canals she had trouble making either her feet or her hands steer her in the right direction. She was only partly on her feet when she was bowled over again in slow motion.
This time she bounced gently twice, taking much longer to hit the ground the second time, and realized that the floor had become steeper. She eventually collected enough of her senses to use the hand lamp that was part of her armor’s equipment.
By this time Charley’s frantic voice was clamoring for attention.
“Molly! I can’t see you! There’s sand still flowing into the hole; are you buried? Can you tell if you’re moving? I don’t dare bring the boat down again until I know where you are!”
“I’m not buried, and you needn’t worry about crushing me,” the Human answered as calmly as she could. “I’m down the hole, apparently. I can see no light but my own, I’m sliding and rolling down a bare rock slope, and I seem to be well ahead of the robot. I don’t think I can have come very far, but I don’t at the moment see how I’m going to get back. The boat will certainly never get in here, I can’t re-program the robot to carry me back downwind, and I don’t think I can climb back on my own; there isn’t enough traction. Any ideas?”
“Just to do what you said if you got in trouble—head back for the others at top speed. Do the rest of you know what’s happened?”
“It seems pretty clear,” said Joe. “Carol’s trouble, amplified, I gather. It would seem best to stay near or even on the robot if you can, Molly; at the moment I am still picking up its broadcast, though if this is what happened to the other one we must expect it to get far enough below the surface to lose the telemeter waves eventually.”
“At the moment I can’t see it, and I think I’m going downhill faster than it does.”
“We’ll have to hope that downhill is also upwind. Keep looking for it, and if you do see it, do your best to get hold of it. Charley’s ropes should be extremely useful. Charley, I assume you’re on your way back for us. I’ll check out the receiver I used for finding the other robots, and we’ll try to get back to your neighborhood in time to measure how far from the original entrance you may have traveled. It should be possible to make a long enough rope in the shop to let one of us follow you and help you climb back, regardless of traction and slope. Jenny, will you see about that?”