Smith had managed to crack the code Saul had used to secure his small army of robots, but only for a short while before it underwent one of its hidden transforms, and so had not managed to take all of them away from him. Saul found the remaining robots scattered about the lattice walls lying between him and the rim, but most were concentrated around Tech Central, which now loomed up to his left, cast into silhouette by the sun. From their slumber he woke up five construction robots, which he summoned to him along with those smaller members of the robot ecology that Smith had ignored, perhaps because they were of little use against the power of Messina’s troops. Remiss of him, for Saul now linked into them, found twenty belonging to a specific subspecies of maintenance robot, and gave them instructions little different from the kind they would normally receive. He then dispatched them throughout the station to repair disabled readerguns and make them accessible only to him. However, he knew that those readerguns, and the construction robots now heading towards them, would not be enough to bring him victory.

Ahead of him lay a mining complex, out of which an ore transit tube rose, like a massive redwood, towards the station’s rim and the smelting-plant dock located there. A huge robot equipped with twin digging wheels sat there frozen, having been shut down in the process of hacking chunks of ore from the ground and transferring them into the fat carrier comprising much of its body. A giant drilling rig on gecko-treaded tracks stood at rest only thirty metres beyond it, its extended robotic arms clamped around an anchor pillar that speared up into the station’s inner structure above his head. It held a new section of pillar destined to fill the gap where a large mass of ore had been removed below. Of course, as they mined out the asteroid, they built the station inwards as well as outwards. All around Saul could see where massive I-beams had been extended downwards and re-anchored, even cases where a few, which had once abutted the asteroid surface some metres apart, now intersected each other and had been joined into one. After kilotonnes of ore had been mined from it to turn into bubblemetals, the asteroid was now substantially smaller than when first brought here from the asteroid belt.

Circumventing the complex put both it and Arcoplex One behind him, and now only the Arboretum cylinder lay ahead, bright in the sunlight peeking round Tech Central over to his left. As he rounded the base structure of the Arboretum, his suit grew uncomfortably warm in open sunlight. Here, no more cylinders lay ahead, just lattice walls rising above him to the station rim. However, these diamond-pattern partitions now terminated up against a solid wall rising sheer from the asteroid surface ahead, marking the near edge of the single break in the rim wheel. A series of ribs braced this great wall, on which monitoring stations and work habitats clung like shellfish to a sea cliff. This barrier hadn’t been here when he had researched the vicinity down on Earth, but it appeared on the station schematic inside his skull. He realized that it had been built to protect the girders of the inner station from the heat generated by the Traveller engine that lay beyond.