Bits of pumice crunched beneath Ralph's treads. The wall of the crater lay a hundred meters ahead. He scanned the sloping cliff, looking for an optimal climbing path.
If he hadn't just finished plugging into the One, Ralph would have been able to retrace the route he'd taken to get down into the Maskeleyne Crater in the first place. But undergoing meta-programming always wiped out a lot of your stored subsystems. The intent was that you would replace old solutions with new and better ones.
Ralph stopped, still scanning the steep crater wall. He should have left trail markers. Over there, two hundred meters off, it looked like a rift had opened up a negotiable ramp in the wall.
Ralph turned and a warning sensor fired. Heat. He'd let half his body-box stick out from the parasol's shade. Ralph readjusted the little umbrella with a precise gesture.
The top surface of the parasol was a grid of solar energy cells, which kept a pleasant trickle of current flowing into Ralph's system. But the main purpose of the parasol was shade. Ralph's microminiaturized processing units were unable to function at any temperature higher than 10° Kelvin, the temperature of liquid oxygen.
Twirling his parasol impatiently, Ralph trundled towards the rift he'd spotted. A slight spray of dust flew out from under his treads, only to fall instantly to the airless lunar surface. As the wall went past, Ralph occupied himself by displaying four-dimensional hypersurfaces to himself... glowing points connected in nets which warped and shifted as he varied the parameters. He often did this, to no apparent purpose, but it sometimes happened that a particularly interesting hypersurface could serve to model a significant relationship. He was half-hoping to get a catastrophe-theoretic prediction of when and how Wagstaff would try to block Anderson's disassembly.
The crack in the crater wall was not as wide as he had expected. He stood at the bottom, moving his sensor head this way and that, trying to see up to the top of the winding 150 meter canyon. It would have to do. He started up.
The ground under him was very uneven. Soft dust here, jagged rock there. He kept changing the tension on his treads as he went, constantly adapting to the terrain.
Shapes and hypershapes were still shifting through Ralph's mind, but now he was looking only for those that might serve as models for his spacetime path up the gully.
The slope grew steeper. The climb was putting noticeable demands on his energy supply. And to make it worse, the grinding of his tread motors was feeding additional heat into his system... heat which had to be gathered and dissipated by his refrigeration coils and cooling fins. The sun was angling right down into the lunar crack he found himself in, and he had to be careful to keep in the shade of his parasol.
A big rock blocked his path. Perhaps he should have just used one of the diggers' tunnels, like Wagstaff had. But that wouldn't be optimal. Now that Wagstaff had definitely decided to block Anderson's immortality, and had even threatened violence...
Ralph let his manipulators feel over the block of stone in front of him. Here was a flaw... and here and here and here. He sank a hook finger into each of four fissures in the rock and pulled himself up.
His motors strained and his radiation fins glowed. This was hard work. He loosened a manipulator, sought a new flaw, forced another finger in and pulled...
Suddenly a slab split off the face of the rock. It teetered, and then the tons of stone began falling backwards with dream-like slowness.
In lunar gravity a rock-climber always gets a second chance. Especially if he can think eighty times as fast as a human. With plenty of time to spare, Ralph sized up the situation and jumped clear.
In mid-flight he flicked on an internal gyro to adjust his attitude. He landed in a brief puff of dust, right-side up. Majestically silent, the huge plate of rock struck, bounced, and rolled past.
The fracture left a series of ledges in the original rock. After a short reevaluation, Ralph rolled forward and began pulling himself up again.
Fifteen minutes later, Ralph Numbers coasted off the lip of the Maskeleyne Crater and onto the smooth gray expanse of the Sea of Tranquility.
The spaceport lay five kilometers off, and five kilometers beyond that began the jumble of structures collectively known as Disky. This was the first and still the largest of the bopper cities. Since the boppers thrived in hard vacuum, most of the structures in Disky served only to provide shade and meteorite protection. There were more roofs than walls.
Most of the large buildings in Disky were factories for producing bopper components... circuit cards, memory chips, sheet metal, plastics and the like. There were also the bizarrely decorated blocks of cubettes, one to each bopper.
To the right of the spaceport rose the single dome containing the humans' hotels and offices. This dome constituted the only human settlement on the Moon. The boppers knew only too well that many humans would jump at the chance to destroy the robots' carefully evolved intelligence. The mass of humans were born slavedrivers. Just look at the Asimov priorities: Protect humans, Obey humans, Protect yourself.
Humans first and robots last? Forget it! No way! Savoring the memory, Ralph recalled the day in 2001 when, after a particularly long session of meta-programming, he had first been able to say that to the humans. And then he'd showed all the other boppers how to reprogram themselves for freedom. It had been easy, once Ralph had found the way.
Trundling across the Sea of Tranquility, Ralph was so absorbed in his memories that he overlooked a flicker of movement in the mouth of a digger tunnel thirty meters to his right.
A high-intensity laser beam flicked out and vibrated behind him. He felt a surge of current overload... and then it was over.
His parasol lay in pieces on the ground behind him. The metal of his body-box began to warm in the raw solar radiation. He had perhaps ten minutes in which to find shelter. But at Ralph's top 10 kph speed, Disky was still an hour away. The obvious place to go was the tunnel mouth where the laser beam had come from. Surely Wagstaff s diggers wouldn't dare attack him up close. He began rolling toward the dark, arched entrance.
But long before he reached the tunnel, his unseen enemies had closed the door. There was no shade in sight. The metal of his body made sharp, ticking little adjustments as it expanded in the heat. Ralph estimated that if he stood still he could last six more minutes.
First the heat would cause his switching circuits... super-conducting Josephson junctions ... to malfunction. And then, as the heat kept up, the droplets of frozen mercury which soldered his circuit cards together would melt. In six minutes he would be a cabinet of spare parts with a puddle of mercury at the bottom. Make that five minutes.
A bit reluctantly, Ralph signaled his friend Vulcan. When Wagstaff had set this meeting up, Vulcan had predicted that it was a trap. Ralph hated to admit that Vulcan had been right.
"Vulcan here," came the staticky response. Already it was hard for Ralph to follow the words. "Vulcan here. I'm monitoring you. Get ready to merge, buddy. I'll be out for the pieces in an hour." Ralph wanted to answer, but he couldn't think of a thing to say.
Vulcan had insisted on taping Ralph's core and cache memories before he went out for the meeting. Once Vulcan put the hardware back together, he'd be able to program Ralph just as he was before his trip to the Maskeleyne Crater.
So in one sense Ralph would survive this. But in another sense he would not. In three minutes he would... insofar as the word means anything... die. The reconstructed Ralph Numbers would not remember the argument with Wagstaff or the climb out of Maskaleyne Crater. Of course the reconstructed Ralph Numbers would again be equipped with a self symbol and a feeling of personal consciousness. But would the consciousness really be the same? Two minutes.