There. Another of the blinding blue flashes, just beyond the window. It was electron-gas blue and it seemed to surround the ship; shafts of blue light shone briefly through the small round windows into the cabin.

The Bell lurched.

Hosch wrapped his thin hands around the support pole. “Why aren’t we dead?”

It was a good question. Clouds of electron gas around a Bell usually meant current surges in the Corestuff hoops. Maybe the cable from the Harbor was fraying, or a hoop failing. But if that was so the Bell’s field would fail almost immediately. The Bell should have imploded by now.

“The current supply is still steady,” Bzya said. “Listen.”

They both held their breath, and looked into the Air; Hosch adopted the empty-eyed expression of a man trying to concentrate on hearing.

Another flash. This time the Bell actually rocked in the soupy underMantle, and Bzya, clinging tightly to the pole, was swung around like a sack. He pulled himself closer to the pole and wrapped his legs around it.

The supervisor’s breath stank of meat and old beercake. “Okay,” he said. “We know the Harbor supply is steady. What’s causing the flashes?”

“There have to be current surges in the Corestuff hoops.”

“If the City supply is steady that’s impossible.”

Bzya shook his head, thinking hard. “No, not impossible; the surges are just caused by something else.”

Hosch’s mouth pursed. “Oh. Changes in the Magfield. Right.”

The Bell wasn’t malfunctioning; the Magfield itself was betraying them. The Magfield had become unstable, and it was inducing washes of charge flow in their protective hoops and dragging them away from their upward path to home.

“What’s causing the Magfield to vary?” Bzya asked. “Another Glitch?”

Hosch shrugged. “Hardly matters, does it? We’re not going to live to find out.”

There was an upward jolt, this time without the accompanying blue flash.

Bzya grasped the pole. “Feel that? That was the Harbor. They’re pulling us up. We’re not dead yet. They’re trying to…”

And then the blue light came again, and this time stayed bright. Bzya felt the writhing Magfield haul at his stomach and the fibers of his body, even as it tore at the Bell itself.

Electron gas sparked from his own fingertips in streamers. It was really quite beautiful, he thought absently.

The Bell was hurled sideways, away from the Spine. Bzya’s hands were torn from the support pole. The Bell’s curving wall came up, like a huge cupped palm, to meet him. His face rammed into a window, hard. His body bent backward as it crammed itself into the tight inner curve of the wall. The structure of the Bell shuddered and groaned, and there was a distant, singing sound above him. That was the cables breaking, he thought through his pain. He felt oddly pleased at his own cleverness at such a deduction.

The walls wrenched, settled; the Bell rolled.

He fell into darkness.

Beyond the transparent walls, huge, ghostly buildings hovered over the humans.

The third chamber was immense, sufficient to enclose a million Parz Cities. The walls — made of the usual gray material, it seemed — were so far away as to be distant, geometric abstractions. Maybe this strange place was a series of nested tetrahedra, going on to infinity…

She Waved to Hork and reached out for him, blindly; still in the chair, he took her hands, and although his grip was strong she could feel the slick of fear on his palms. For a heartbeat she felt an echo of the passion they’d briefly found, in flight from terror during the journey.

The transparent structures hovered around them like congealed Air. They were translucent boxes hundreds of thousands of mansheights tall. And within some of the buildings more devices could be seen, embedded; the inner structures were ghosts within ghosts, gray on gray.

The tetrahedral box containing the “Pig,” the solid little chair, Hork and Dura themselves, were like specks of wood adrift in some mottled fluid. In fact, she realized, the whole of the tetrahedron they occupied was embedded inside one of the huge buildings; its gray lines sectioned off the space around them, and she looked out through its spectral flesh.

“Why do you suppose we can’t see these things clearly? And I wonder what their purpose is. Do you think…”

Hork was peering up at the “building” they were embedded in. He stared into its corners and at its misty protuberances, and then glanced down quickly at the chair he sat in.

“What’s wrong?”

“The ghost-building we’re inside. Look at it… It has the same shape as this chair.” The gray light of the translucent forms pooled in his eyecups. “It’s a hundred thousand times the size, and it’s made of something as transparent as clearwood and thinner than Air… but nevertheless, it’s an immense — spectral — chair.

She lifted her head. Slowly she realized that Hork was right. This immense “building” — at least a meter tall — had a seat, a back; and there, so far above her it was difficult to see, were two arms, each with its control lever.

Hork grinned, his face animated. “And I think I know what it’s all for. Watch this!”

He twisted his body. His chair swiveled in the Air.

She gasped, Waving away in alarm; but the chair came to rest, and no damage seemed to have been done. “What are you doing?”

“Don’t you understand yet? Look up!”

She tilted her head back.

The other “chair” — the ghostly analogue — had turned too, swiveling to match Hork’s lurch.

“See?” he crowed. “The chair is keyed to mine, somehow; whatever I make mine do, the big one must follow.” Hork swung this way and that, laughing like a child with a toy. Dura watched the giant analogue dance clumsily, aping Hork’s movements like some huge pet. Presumably, she thought, when the device swiveled, its substance must be moving around her — through her, in fact, like an unreasonable breeze. But she felt nothing — at least, no more than an inner chill which could as easily be caused by her awe and fear.

At last Hork tired of his games. “I can make it do whatever I want.” He looked a little more thoughtful. “And so if I pull these levers…”

“No. We need to work this out, Hork.” She looked up. “This — ghost, this City-sized artifact — is a seat big enough for a giant…”

“That’s obvious. But…”

“But,” she interrupted, “a giant of a certain form… a human-shaped giant, meters tall.” She studied his face, waiting for him to reach the same conclusions.

“Meters… The Ur-humans.”

She nodded. “Hork, I think the ghost-seat is an Ur-human device. I think we’re in a little bubble of Air, floating inside an Ur-human room.”

She tilted her head back on her neck, feeling the flesh at the top of her spine bunch under her skull, and looked up into a ghost-room which abruptly made sense.

They were inside a huge Ur-human chair. But there were other chairs — four of them, she counted, receding into mistiness, like a row of cities. The chairs were placed before a long, flat surface, and she caught hints of a complex structure beneath and behind that surface. Perhaps that was some form of control panel. Looking further out, the tetrahedral structure surrounding all of this was a sketch drawn against fog.

Hork touched her arm. “Look over there.” He pointed. On the side of the Ur-human room opposite the row of seats there was a bank of billowing gas — but that must be wrong, of course; she tried to forget her smallness, to see this through Ur-human eyes. It was a structure made up of something soft, pliable, piled up on a lower flat surface. It looked like a cocoon, laid flat.

Did the Ur-humans sleep?

Again Hork was pointing. “On top of that surface before the chairs. See? Instruments, built for giant hands.”