“What is it now?” Farr whispered.

“We think we’ve snagged a berg…”

Below the surface of the Quantum Sea, nuclei — clusters of protons and neutrons — could not survive. And deeper still, in the dark belly of the Sea itself, densities became so high that the nucleons themselves were brought into contact. Hyperons, exotic combinations of quarks, could form from the colliding nucleons. The hyperons could combine into stable islands of dense material — Corestuff bergs — which could persist away from the formative densities of the heart of the Star. The bergs drifted up, in Quantum Sea currents, to higher levels to be retrieved by the Fishermen and returned to Para City.

“It’s clinging to the outside of the Bell,” Bzya said. He mimed the impact of the berg against the Bell with his fists. “See? It’s drawn there by the magnetic field of the Bell, of its Corestuff hoops. And it stays, stuck by the Magfield set up in response in its own interior.”

Hosch grinned again, and Farr was aware of the supervisor’s foul breath. “Good Fishing. We were lucky. We can’t be more than four meters below Parz. Now, boy. Watch.” With a grandiloquent gesture, Hosch closed the two switches on the small control panel beside him.

Farr held his breath, but nothing seemed to have changed. The Bell still swayed alarmingly through the underMantle — in fact it seemed to be rotating, his stomach told him, perhaps knocked into a twist by the impact of the berg.

Bzya said patiently, “He’s sent a signal to the Harbor, along the cables. That we’re ready to be hauled up.”

Hosch grinned at him. “And that’s why we’re here, boy. That’s the reason they put men in these cages, and stuff them down into the underMantle. All to close those little switches. See? Otherwise, how else would the Harbor know when to haul up the Bells?”

“Why three of us? Why not just one Fisherman?”

“Double redundancy,” Hosch said. “If something hit the mission — well, one of us might live long enough to throw the switches, and bring home the precious Corestuff.” He was obviously relishing teasing out Farr’s fear.

Farr tried to bite back. “Then you should have told me what was going on before. What if something had gone wrong, and I hadn’t known what to do?”

Bzya regarded Hosch impassively. “The boy has a point, Hosch.”

“Anyway,” Farr said, “it can’t take much skill to throw a simple switch…”

“Oh, that’s not the skill,” Hosch said quietly. “The skill is in staying alive long enough to do it.”

The Bell lurched alarmingly through the underMantle, unbalanced by the mass of Corestuff clinging to its side. Farr tried to judge their ascent, but he couldn’t separate genuine indications of their rise to the light — the sensations in his belly, a lightening of the gloom in the small windows — from optimistic imagination. He gazed anxiously at the bruised-purple glow in the windows, unable to take any of the food Bzya offered him from a small locker set in the hull of the Bell.

The Bell shuddered under a fresh impact. Farr clung to his pole. There was a grinding noise, and the clumsy little craft shuddered to a halt.

Farr resisted the temptation to close his eyes and curl up. What now? What else can they throw at me?

He felt Bzya’s rough fingertips on his shoulders. “It’s all right, lad. That’s a sign that we’re nearly home.”

“What was it?”

“That was our berg, scraping against the Spine. We’re only a meter or so below Parz itself now.”

Hosch hauled at a lever on the control panel, grunting with the effort; the hum Farr had learned to associate with the currents supplying the Bell’s protective magnetic field decreased in intensity. Hosch turned to him, his mood evidently swinging toward its calm, sly pole. “Your buddy here is half-right. But we aren’t safe yet. Not by a long way.”

In fact this was one of the most dangerous parts of the mission. The berg, rattling against the Spine, could easily sever their cables or damage the Spine itself.

“So,” Hosch said silkily, “one of us has to go outside and do some work.”

“What work?”

“Wrap ropes around the berg. Lash it to the Bell,” Bzya said gently. “That’s all. Stops the berg from shaking loose, and protects the cables from collisions with the Corestuff.”

Hosch was staring at Farr.

Bzya held up his huge hands. “No,” he said. “Hosch, you can’t be serious. You can’t send the boy out there.”

“I’ve never been more serious,” Hosch said. “As you’ve both been telling me, the boy won’t last five heartbeats down here unless he learns the trade. And there’s only one way to do that, isn’t there?”

Bzya made to protest, but Farr stopped him. “It’s all right, Bzya. I’m not afraid. He’s probably right, anyway.”

Bzya said, “Listen to me. If you were not afraid you would be a fool, or dead. Fear keeps your eyecups open and clean.”

“Ropes in that locker,” Hosch said, pointing.

Bzya started to haul out the tightly packed, thick ropes; soon the little cabin seemed filled with the stuff. “And you,” Hosch snapped at Farr. “Get the hatch open.”

Farr looked through the window. The Air — if it could be called Air, this deep — was purple, almost Sea-like. He was still, after all, a full meter — a hundred thousand mansheights — below Parz.

He felt the sole of a foot in his back. “Get on with it,” Hosch growled. “It won’t kill you. Probably.”

Farr put his shoulders to the circular hatch and pushed. It was heavy and stiff, and as he pushed he heard the scraping of the Corestuff hoops binding up the capsule as they slid away.

The hatch burst open, flying out of his reach. The Air outside the Bell was thick and glutinous, and it crowded into the cabin, overwhelming the thinner, clear Air within. The light of the cabin’s lamps seemed immediately dimmed.

Farr held his breath, his mouth clamped closed almost of its own accord. There was a pressure on his chest, as if the thicker Air were trying to force itself into his lungs through his skin. With an effort of will he dragged his lips apart. The cloying, purple Air forced its way into his throat; he could feel it on his lips, viscous and bitter. He heaved, expanding his lungs; the stuff burned as it worked through his capillaries.

So, after a brief few heartbeats of struggle, he was embedded in the underMantle. He raised his arms experimentally, flexing his fingers. His movements were unimpaired, but he felt weaker, sluggish. Perhaps the superfluid fraction of this Air was lower than in the true Mantle.

“The hatch,” Bzya said, pointing. “You’d better retrieve it.” Bzya’s voice was obscured, as if he was speaking through a layer of cloth.

Farr nodded. He pushed his way out of the hatchway.

The yellow-purple Air was so thick it barely carried any illumination; it was as if he was suspended in a dark-walled bubble about four mansheights across. The Bell was suspended at the center of the bubble, a drifting bulk. Beyond it the Spine was a wall, massive and implacable, its upper and lower extremes lost in the misty obscurity of the Air. Looking at the Spine now Farr could see cables of Corestuff wrapped around it and laid out along its length — cables which must provide a magnetic field like the Bell’s, to keep the Spine from itself dissolving in the lower underMantle. The Bell’s own cables snaked up and out of sight toward the world of the upperMantle, a world which seemed impossibly distant to Farr.

The loose hatch was a short distance from him. He Waved to it easily enough, although the Air in which he was embedded was a cloying presence around him. He caught the hatch and returned it briskly to Bzya.

“Now the berg,” Hosch called. “Can you see it?”

Farr looked. There was a shape, lumpen, lodged between the Bell and the Spine. It was half a mansheight long, dark and irregular, like a growth on the clean, artificial lines of the Bell.