The hole wasn’t big enough. Horza saw it coming towards him and knew straight away. He used one shaking finger on the laser beam-spread control set in the semi-wheel of the controls, turning the spread up to maximum then firing once more. The screen washed out with light again, all around the perimeter of the hole. The CAT stuck its nose and then its body into another Smallbay. Horza waited for something to hit the sides or roof of the white-hot gap, but nothing happened; they sailed through on their three pillars of fire, throwing light and wreckage and waves of smoke and gas before them. The dark waves blasted out over shuttles; the whole Smallbay they were now moving slowly through was full of shuttles of every shape and description. They were floating over them, battering them and melting them with their fire.
Horza was aware of Wubslin sitting on the seat beside him, his eyes locked onto the view ahead, his legs drawn up as far as possible so that his knees stuck up above the edge of the console, and his arms locked in a sort of square over his head, each hand grasping the bicep of the other arm. His face was a mask of fear and incredulity when Horza turned round to glance at him, and grinned. Wubslin pointed frenziedly at the main screen. “Watch!” he shrieked over the racket.
The CAT was shaking and bouncing, rocked by the stream of superheated matter pouring from under its hull. It would be using the atmosphere around it to produce plasma, now that there was air available, and in the relatively confined space of the Smallbays the turbulence created was enough to shake the vessel bodily.
There was another wall ahead, coming up faster than Horza would have liked. They were slewing slightly again as well; he narrowed the laser angle again and fired, pulling the ship round at the same time. The wall flashed once around its edges; the roof and floor of the Smallbay flashed in loops of flame where the laser caught them, and dozens of parked shuttles ahead of them pulsed with light and heat.
The wall ahead started to fall slowly back, but the CAT was coming up on it faster than it was crumpling. Horza gasped and tried to pull back; he heard Wubslin howl, as the vessel’s nose hit the undamaged centre of the wall. The view on the main screen tilted as the ship rammed into the wall material. Then the nose came down, the Clear Air Turbulence quivered like an animal shaking water from its fur, and they were rocking and yawing into yet another Smallbay. It was totally empty. Horza gunned the engines a little more, took a couple of bursts with the laser at the next wall, then watched in amazement as this wall, instead of falling back like the last one, crashed down towards them like a vast castle drawbridge, slamming in one fiery piece onto the deck of the empty Smallbay. In a fury of steam and gas, a mountain of water appeared over the top of the collapsing wall and poured out in a huge wave towards the approaching ship.
Horza heard himself shouting. He rammed the motor controls full on and kept the laser fire button hard down.
The CAT leapt forward. It flashed over the surface of the cascading water, enough of the plasma heat smashing into its liquid surface to instantly fill all the space of Smallbays its passage had created with a boiling fog of steam. As the tide of water continued to pour from the flooded Smallbay and the CAT screeched above it, the air about the ship filled with superheated steam. The external pressure gauge went up too quickly for the eye to follow; the laser blasted even more vapour off the water in front, and with an explosion like the end of the world the next wall blew out ahead of the vessel — weakened by the laser and finally blasted away by the sheer pressure of steam. The Clear Air Turbulence shot out from the tunnel of linked Smallbays like a bullet from a gun.
Motors flaming, in the middle of a cloud of gas and steam which it quickly outdistanced, it roared into a canyon of air-filled space between towering walls of bay doors and opened accommodation sections, lighting up kilometres of wall and cloud, screaming with its three flame-filled throats, and seemingly pulling after it a tidal wave of water and a volcano-like cloud of steam, gas and smoke. The water fell, turning from a solid wave into something like heavy surf, then spray, then just rain and water vapour, following the huge flapping card of the bay door tumbling through the air. The CAT wrenched itself round, twisting and slewing through the air in an attempt to check its headlong rush towards the far wall of Smallbay doors facing it across that vast internal canyon. Then its motors flickered and went out. The Clear Air Turbulence started to fall.
Horza gunned the controls, but the fusion motors were dead. The screen showed the wall of doors to other bays on one side, then air and clouds, then the wall of bay doors on the other side. They were in a spin. Horza looked over at Wubslin as he fought with the controls. The engineer was staring at the main screen with a glazed expression on his face. “Wubslin!” Horza screamed. The fusion motors stayed dead—
“Aaah!” Wubslin seemed to have woken up to the fact that they were falling out of control; he leapt at the controls in front of him. “Just fly it!” he shouted. “I’ll try the primers! Must have over-pressured the motors!”
Horza wrestled with the controls while Wubslin tried to restart the engines. On the screen, walls spun crazily about them and clouds beneath them were coming up fast — beneath them; really beneath them; a dead flat layer of clouds. Horza shook the controls again.
The nose motor burst into life, guttering wildly, sending the spinning craft careering off towards one side of the artificial cliff of bay doors and walls. Horza cut the motor out. He steered into the spin, using the craft’s control surfaces rather than the motors, then he aimed the whole ship straight down and put his fingers on the laser buttons again. The clouds flashed up to meet the vessel. He closed his eyes and squeezed the laser controls.
The Ends of Invention was so huge it was built on three almost totally separate levels, each over three kilometres deep. They were pressure levels, there because otherwise the differential between the very bottom and the very top of the giant ship would have been the difference between standard sea level and a mountain top somewhere in the tropopause. As it was, there existed a three and a half thousand metre difference between the base and roof of each pressure level, making sudden journeys by traveltube from one to the other inadvisable. In the immense open cave that was the hollow centre of the GSV the pressure levels were marked by force fields, not anything material, so that craft could pass from one level to another without having to go outside the vessel, and it was towards one of those boundaries, marked by cloud, that the Clear Air Turbulence was falling.
Firing the laser did no good whatsoever, though Horza didn’t know that at the time. It was a Vavatch computer, which had taken over the internal monitoring and control from the Culture’s own Minds, which opened a hole in the force field to let the falling vessel through. It did so in the mistaken assumption that less damage would be caused to The Ends of Invention by letting the rogue vessel fall through than having it impact.
In the centre of a sudden maelstrom of air and cloud, in its own small hurricane, the CAT burst through from the thick air at the bottom of one pressure level and into the thin atmosphere at the top of the one below. A vortex of rag-clouded air blew out after it like an inverted explosion. Horza opened his eyes again and saw with relief the distant floor of the GSV’s cavernous interior, and the climbing figures on the main fusion motors’ monitor screens. He hit the engine throttles again, this time leaving the nose motor alone. The two main engines caught, shoving Horza back in his seat against the cloying hold of the restrainer fields. He pulled the nose of the diving craft up, watching the floor far below gradually disappear from view as it was replaced by the sight of another wall of opened bay doors. The doors were much larger than those of the Smallbays in the level they had just left, and the few craft Horza could see either nosing into or appearing out of the lit lengths of the huge hangars were full-size starships.