The paralysing shock stabbed clear through to his feet.

His muscle control instantly disrupted, Dallen sagged and fell — then recovery came and he clung to the ladder, gasping with fright. He had almost dropped the whole way to the metal deck, a lethal twenty metres below, and had been saved only by the fact that his nail had served as a partial barrier to the Pietzoff s neural charge. And Mathieu was due to return at any second. Striving for full control over his body, Dallen inched upwards to regain the height he had lost. He squeezed the solvent sponge to activate it, wiped the top rung free of paint and got to the bottom of the ladder just as Mathieu appeared with a mop and bucket which could have been props from a period play.

"I love these high-tech solutions to the problems of space flight," he said, gamely cheerful as he set to work on the water-beaded deck, looking like a blond holo star making a bad job of playing a menial.

Dallen nodded, still slightly shaky, still baffled by his experience at the head of the ladder. By all the rules governing such things, Mathieu should have taken the big drop and hit the deck like a sack of bones. Was it possible that his right hand was an extremely lifelike prosthetic? Or was it merely, returning to the prosaic, that there had been an uneven distribution of crystals in the emulsion and Dallen had chosen the wrong place for his test? It hardly seemed likely, but it was the most acceptable explanation he could devise. Nobody was immune to Pietzoff.

"To think I gave up a good job for this," Mathieu said, mopping with casual efficiency. "I must have been crazy."

"Why did you pack it in? Was it Bryceland?"

"Bryceland? Mal-de-mayor?" Mathieu's eyes showed a cool amusement. "No, Carry, it was time for me to travel, that's all."

"I see." Again Dallen found it difficult to cope with the complexity of his reactions to Mathieu. The fact mat the man had been spared a summary execution did not mean mat he should be allowed to avoid the establishment's penalty for a major crime, but was it now too late to bring an accusation against him? What evidence would remain at this late stage? And, underlying everything else, why did the man himself seem to have changed? The difference was indefinable, but it was there. Gerald Mathieu had always given him the impression of being a vain gadfly, a hollow man, but now…

What's the matter with me? Dallen demanded of himself in bemused wonderment. Why am I where Silvia isn't?

He gave Mathieu a dismissive wave, walked back to the elevator and pressed the button for Deck 5. The cage made its customary shuddering ascent, passing layer after layer of miniature grassy plains, some in shadow, others bathed in artificial sunlight. By the time it halted at the ring deck Dallen had relegated Mathieu to the past. Nobody was about — the Hawfe-bead's crew spending virtually all their working hours in the outer hulls — and he was able to go without delay to Silvia's cabin. He was keyed-up and exhilarated as he pressed the door handle, so preternaturally alive mat he could actually feel the subtle agitation of the ship's air. The handle refused to turn. Dallen tapped lightly on the door and stepped back a little, disappointed, when it was opened by the solidly androgynous figure of Doctor Billy Glaister.

"Silvia can't see you now," she announced triumphantly. "She's got to…"

"It's all right, Billy," Silvia said, appearing beside the other woman. In the short interval since Dallen had last seen her, she had brushed her hair back and had dressed in a black one-piece suit. She came out of the cabin, drew the door to, caught Dallen's arm and walked him towards the nearby stair.

"I'm sorry," she said. "Billy is inclined to be over-protective."

"Is that what you call it?"

"That's what it a." Silvia halted and gave him a very wise, very womanly smile. "When you cool down a little you'll be as glad as I am that she came back. This place isn't for us, Carry. Admit it."

Dallen glanced at the environment of smudged metal walls, stanchions and pipe runs. "It's idyllic."

She laughed and, in an unexpected gesture, raised the back of his hand to her lips and kissed it, somehow proving to him that all was well. "Carry, we'll reach Optima Thule in a day or two and as soon as Rick unloads his grass well be going on to Beachhead City, where there are good hotels, and where well have all the time we need to be together and make our plans. That's worth holding on for, isn't it?"

He looked down at her, unable to admit she was right, and forced himself to return her smile.

By the time another day had passed the ship had ceased most of its geometrical manipulations and was rapidly reaching a condition in which it could be perceived as a real object by outside observers. That, in turn, meant that human and inorganic watchers aboard the vessel could once again receive information from the normal space-time continuum.

Still shedding velocity at a rate of more than 1G, the Hawkshead took its bearings from Orbitsville's beacon network and began making course corrections, heading for Portal 36. The entrance had been assigned to k by the Optima Thule Science Commission because the surrounding terrain had never been contaminated by developers and therefore would yield the cleanest data in large-scale botanical experiments.

Professional space travellers rarely devoted any time to visual observation during final approaches to Orbitsville. At close ranges the vast non-reflective shell had always occluded half the universe, cheating the eye and confusing the intellect, creating the impression that nothing existed where in fact there was an impenetrable wall spanning the galactic horizon.

Thus it was that no member of the Hawkshead’ s crew was at a direct vision station when the vessel, guided by artificial senses, began groping its way towards Portal 36.

And thus it came about that it was Doctor Billy Glaister, habitual visitor to the ship's observation gallery, who discovered that Orbitsville had undergone a radical change.

The enigmatic material of its shell — black, immutable, totally inert in two centuries of mankind's experience — was suffused with a pulsing green light.

.The onset of weightlessness, gradual though it was, brought problems for Da lien.

In the early stages Cona had enjoyed her growing gymnastic ability, and had come dangerously close to hurting herself or Mikel during exuberant and ill-coordinated frolicking about the cabin. Then, as the Hawkshead’ s main drive neared total shutdown, the feeling of unnatural lightness progressed to become an outright falling sensation, and Cona's pleasure turned to fear. She clung to the frame of her bed, white-faced and whimpering, but resisted his efforts to secure her with the zero-G webbing. Mikel was more manageable, allowing himself to be tethered to his cot, and seemed less concerned with himself than with his toys' new tendency to float away in the air.

Dallen was retrieving a favourite model truck for him when a single chime from the communications panel signalled that the ship was entering the state of free fall. An uneasy lifting sensation in Dallen's stomach was accompanied by the sound of Cona retching.

Cursing himself for not having been prepared, he twisted towards her just in time to be caught in the skeins of yellowish fluid which had issued from her mouth. The acid smell of bile filled the cabin at once and Mikel began to sob.

Fighting to keep the heaving of his own stomach in check, Dallen drew a suction cleaner pipe out of the wall and used it to hunt down every slow-drifting globule. It took him another five minutes to clean himself and change his clothes, by which time his thoughts were turning away from his domestic troubles and towards truly macroscopic issues. As soon as the flickerwing drive had been deactivated the Hawkshead would have been able to enter radio contact with Orbitsville and request some kind of official explanation for what had happened to the shell. Presumably Captain Lessen already had the information, but — disturbingly — there had been no general announcement.