take good care of yourself. I’d keep you here, but… You take care of yourself, Sam. You hear me?”
Sam had nodded. “Yes, sir. Do you mean you can make other brains exactly like mine?”
“Technically, the control computer can duplicate ypur design,” DeMatre had answered. “It won’t be just like your brain. Too many random factors in any really advanced mechanical mind unit. But with similar capabilities. That’s why you’re worth more money than this whole project without you. You’re worth quite a few million dollars, and it’s up to you to see that valuable property like that isn’t destroyed. Right, Sam?”
Sam had agreed and been shipped back to the Moon, along with the first of the Mark Three robots. And maybe his trip to the research center had been of some use, since the new Mark Three models worked as well as their limitations permitted. They were far better than the preceding models.
Maybe he wasn’t valuable enough to men for them to come for him now. But by DeMatre’s own words, he was one of their most valuable possessions. If it was up to him to see that he wasn’t destroyed, then it was up to him also to see that he wasn’t lost to men.
If they couldn’t come for him, he had to get to them. The question was: How? He couldn’t project himself by mind power like John Carter. He had to have a rocket!
With the thought, he went dashing out through the entrance and heading toward the old wreck. It stood exactly as it had after the landing that had ruined it, with half its hull plating ripped off and most of its rocket
motors broken. It could never be flown again. Nor could the old supply capsules. They had burned out their tubes in getting here, being of minimum construction. There wasn’t even space inside one for him.
Sam considered it, making measurements and doing the hardest thinking of his existence. Without the long study of all the technical manuals of the dome library, he could never have found an answer. But eventually he nodded.
A motor from the big ship could be fitted to a capsule. The frame would be barely strong enough. But the plating could be removed to lighten the little ship; Sam needed no protection from space, as some of the cargo had required. And the automatic guidance system could be removed to make enough room for him. He could operate it manually, since his reaction and integrating time were faster than that of even the system.
Fuel would be a problem, though there was enough oxygen in the dome storage tanks. It would have to be hydrogen, since he could find rocks from which that could be released by the power of the generator. Fortunately, lunar gravity was easier to escape than that of Earth.
He went back to the dome and found paper and pencil. He was humming softly to himself as he began laying out his plan. It wasn’t easy. He might not be skilled enough to pilot the strange craft to the station. And it would take a great deal of time. But Sam was going to the men who wouldn’t come to him!
4
It takes experience to turn engineering theory into practice. Almost three years had passed since Sam’s awakening before the orbital station swam slowly into view before him. And the erratic takeoff and flight had been one that no human body could have stood. But now he sighted on the huge metal doughnut before him, estimating its orbit carefully. There were only a few gallons of fuel remaining in the tanks behind him, and he had to reach the landing net on the first try.
His first calculations seemed wrong. He glanced down at the huge orb of Earth and flipped sun filters over his eyes. Something was wrong. The station was not holding its bottom pointed exactly at the center of Earth as it should have done; it was turning very slowly, and even its spin was uneven, as if the water used to balance it against wobbling had not been distributed properly. Beside it, the little ferry ship used between station and ships from below was jerking slightly on the silicone-plastic line that held it.
Sam felt an unpleasant stirring in his chest where most of his brain circuits lay. But he forced it down and computed his blast for all the factors. He had learned something of the behavior of his capsule during the minutes of takeoff and the later approach to the station. His fingers moved delicately, and fuel metered out to the cranky little motor.
It was not a perfect match, but he managed to catch himself in the net around the entrance to the hub. He pulled himself free and began scrambling up to the lock as the capsule drifted off. A moment later, he was standing hi the weightlessness of the receiving section. And from the sounds of his feet, there was still
He froze motionless as he let himself realize he had made it. Then he began looking for the men who should have seen his approach and be coming to question him.
There was no sound of steps or of any other activity, except for his own movements. Nor was there any light from the bulbs above him. The only illumination was from a thick quartz port that faced the sun.
Sam cut on the lamp built into his chest and began sweeping the sections of the hub with its light. Dust had formed a patina here, too. He sighed softly into the air. Then he moved toward the outer sections, his steps determined.
Halfway down the tube that ran from the hub to the outer hull, Sam stopped and cut off his light. Ahead of him, there was a glow! Lights were still burning!
He let out a yell to call the men and began running, adjusting for th^j increasing feeling of weight as he moved outwariSv’Then he was under the bulb. He stared up at it—a single bulb burning among several others that were black, though they were on the same circuit. How long did it take for these bulbs to burn out? Years surely, and probably decades. Yet most of the station was in darkness, though there was still power from the atomic generator.
He found a few other bulbs burning in the outer station, but not many. The great reception and recreation room was empty. Beyond that, the offices were mostly open and vacant. Some held a litter of paper and other stuff, as if someone had gone through carelessly, not bothering to put anything back hi place. The living section with its tiny sleeping cubicles was worse. Some of the rooms were simply bare, but others were in complete disorder. Four showed signs of long occupancy, with the sleeping nets worn almost through and not replaced. But nothing showed how recently they had been left.
He went through another section devoted to station machinery and came to a big room that was apparently now used for storage. Sam had seen a plan of the station in one of the technical books in the dome. He placed this room as one designed as a storage for hydrogen bombs once. But that had been from the precivi-lized days of men, and the bombs had been dismantled and destroyed more than sixty years before.
It was in the hydroponics room that he was forced to face the truth. The plants there had been the means of replacing the oxygen in the air for the men, and now the tanks were dry and the vegetation had been dead so long that only desiccated stalks remained. There could be no men here. He didn’t need the sight of the bare food section for confirmation. Some men had stayed here until the food was gone before they left the un-tended plants to die. It must have been many years ago that they had abandoned the station.
Sam shook his head in anger at himself. He should have guessed it when he saw that there were none of the winged rocket ships waiting outside the station. So long as men were here, they would have kept some means for return to Earth.
The observatory was dark, but there was still power for the electronic telescope. The screen lighted at his touch, showing only empty space. He had to wait nearly two hours before the slow tumble of the station brought Earth into full view.
Most of it was in daylight, and there was only a thin cloud cover. Once a thousand cities could have been scanned plainly from here. When seeing was best, even streams of moving cars could be seen. But now there were no cities and no signs of movement!
Sam emitted a harsh gasping sound as he scanned the continent of North America. He had seen pictures of New York, Chicago, and several other city complexes from this view. Now there was only dark ruin showing where they had been. It came to him with an almost physical shock that perhaps millions of human beings had died in those wrecks of cities.
There were still-smaller towns where he could make out the pattern of houses. But there was no movement, even there.
He cut power from the telescope with an angry flick of his finger, trying to blot the things he had seen from
