He hazarded a rough guess: "It will take me months! Years, if I stop to sleep."
"Nonetheless. That is your only legal course of action."
Phaethon rotated his floating body to peer once more over the edge of the rim. He could see the energy units, like lines in a Greek column, descending away from him, infinitely.
There would be no danger until gravity started to reassert itself. He could just drift down, slowly at first, never noticing the gently mounting acceleration, never seeing the danger until it was too late, until he was speeding down, faster and faster, with no way to stop himself. No way except to engage the energy units with a magnetic grappling field. Would they truly fail to support him?
Surely there was an emergency circuit to catch falling objects, to prevent damage to the bottom, if nothing else. Surely the Sophotechs, who were so wise, would not simply stand by idly, and watch him fall and watch him die? Would they protect Vafnir's property rights so jealously, when a mere flick of a switch to the energy units, a few micrograms of power, would save a human life? Wouldn't Vafnir's lack of action be a crime?
Foolish thoughts. No law would protect a man who voluntarily walked off a ledge.
Suicide, after all, was not against the law in the Golden Oecumene.
Curled into a ball like a fetus, barely able to keep his eyes on his target, Phaethon ejected a few desultory squirts of steam and bobbed over to the air lock entrance of the service stair. The air lock was the size of a coffin. It whined as it cycled. The atmosphere beyond was thin, high in inert gasses, meant to maintain basic pressure, not meant for humans to breathe. The stairwell beyond was dark, narrow, and barren.
Stairs in microgravity?! Obviously no one had ever bothered to program this segment of the service access way to react intelligently to the surrounding circumstances.
There was hardly enough room to maneuver. He kicked off the door and fell to the next landing, rotating at the halfway. His foot hit the far wall with a dull clang. He kicked off again. He fell down to the next landing. The far wall clanged under his boot. The echo resounded down the long, long, shaft underfoot, a large, hollow, endlessly empty noise.
Already he was exhausted. And there were roughly fifteen million flights of stairs left to go.
He kicked off the wall again. The metallic echoes clanged through the emptiness.
THE DESCENT
Slowly, gradually, the weight grew heavier and heavier. Slowly, the air grew heavier. Slowly, the burden in his mind grew heavier.
There were things he did to keep despair and grief at bay. All he had to do, he told himself, was think about it later. Let him get down the tower first. Let him get to Talaimannar in Ceylon. Harrier Sophotech must have had something in mind when he named that city; Phaethon had that as his goal, as his hope. He saw no further.
Flying, one long kick after another, down the first hundred flights of stairs, he had exhaustively inventoried the macro-commands and routines loaded into his personal thought-space, the vast mental hierarchy of (now useless) controls in his armor, the amount and composition of the nanomachinery in his black cloak and skin garment.
Then he busied himself by arranging a priority list for his cloak and inner garment, which he expected could shelter, feed, water, and nurse him. He went through a system check on the armor. When he was done with that, because he had nothing else to do, he did it again. Then a third time ...
There came a time when he had to skip; a push of the toe was enough to send him down the next flight of stairs. Each landing slapped his feet more heavily. Then there came a time
when he had to walk. He walked, he marched. Then he trudged. Then he plodded. The weight seemed always to grow more. Each time he thought that he was finally far enough down the tower length to suffer the normal Earth gravity, the next hour or so of descent seemed only to make it all heavier.
For some of the flights of stairs, he rested his legs, letting the leg motors do all the work, folding his legs in lotus position on the open belly plate of the armor's midriff. But once his priority list was done, and he calculated the drain on his suit energy, he realized that the batteries could not be recharged indefinitely, and perhaps should be conserved.
But conserved for how long? No one was ever going to sell him a gram of antimatter again. Perhaps he could build a simple solar converter out of the nanomaterial in his cloak. But was this cost-effective? He had only a limited amount of nonrecyclable cloak material. Clearly he had to use it for some things and not others, such as the production of food and water for himself.
He told himself not to think about the future. Get to Ta-laimannar in Ceylon. That was the goal.
He shut off his leg motors, folded his cape, and walked down the stairs using his legs.
Down more stairs he trod. And then more, and more.
The last hour before he slept, he began accumulating carbon out of the air around him into his cloak. The weight began to slow him, but he spent some of his power to increase the action of his leg motors to tolerate the extra burden. He stopped to rest on a landing, consulted the thousands of ecological programs he had loaded in his thoughtspace, and built a place to sleep out of the nanomaterial of his cloak.
His little encampment spread across the landing and up several steps. He had accumulated enough carbon, nitrogen, and water vapor out of the air to combine complex amino acids in a life-filter canister he grew from his cloak. He car-
peted the landing with soft moss on which he could rest, and his vapor canister, converted to a condenser, and placed at the top stair, was able to put out a little streamlet of water. This trickled down the mossy stairs, and fell into his helmet. Inside the helmet he had his nanomachines construct a nuclear recycler to break up the water, store the hydrogen, and release the fresh oxygen back into the atmosphere. The mildly higher partial pressure of oxygen refreshed him without leading to drunkenness.
He decided that it would not be too wasteful of his limited material to construct a few simple microorganisms, which he introduced into the streambed, and which he programmed to a symbiotic interrelationship with the moss of the stair. Nanomachines gathered nitrogen from the air and herded it together into floating spores; inside the spores, other machines rearranged the materials into simple nutrients to keep the moss green and healthy during the night, and to convert the moss into sugars and carbohydrates, starches and vitamins, so that Phaethon could have a bland, if nourishing, meal in the morning. Wastes from the groin piece of his armor he buried and filtered in a mound of moss which he then dotted with perfumed flowers; and the recycling spores gathered here like flies, to draw out elements to feed the moss. There was no sunlight here, of course. The energy for his little ecosystem came from his armor, for he had adjusted the outer plates to radiate in the infrared, and draped the whole affair in a ther-mophilic fungus organism like pale seaweed, to photosynthe-size heat energy and start the simple food chain.
The control hierarchies within the armor, designed to run the complex interconnected machine-and-organic ecologies of a starship, would have had more than enough capacity to track and control this tiny plot of moss ten steps across; but Phaethon did not have a responder, or a radio set, or a point-to-point system that a child could buy for a pfennig from a thought shop, and so there was no way for any command to reach from the suit-mind to the microorganisms. Phaethon had to content himself with a crude, old-fashioned binary chemical tag system, loading each cell with little viruses to
disintegrate them if they passed outside of the area, or a time, or the behavior, defined by his preset chemical cues.
He folded himself in spun silk polymer sheets, and sat on other sheets inflated with air to form a pillow beneath. He propped the armor up, so it sat facing him, and the warmth from the glowing red breastplate and vambraces was like a camp stove.