Hork looked like a reprimanded child. "Well, as you told me earlier, we're not going to make any progress unless we take a few chances." He glanced down at the arrow device inset in the left arm of the seat. "What about this, for instance?"

Dura Waved closer. The arrow was a finger-thick cylinder hinged at its center; it lay at the heart of a small crater gouged out of the chair. The crater's rim was marked by a band divided into four quarters: white, light gray, dark gray, black. The arrow was pointing at the black quadrant. It seemed obvious that the arrow was designed to be twisted by the occupant of the chair.

Hork looked up at her. "Well? This seems harmless enough."

Dura suppressed a manic giggle. "You haven't the faintest idea what it is..."

"Damn you, upfluxer, we didn't come all this way to cower." And with a convulsive movement he grabbed the arrow and twisted it.

The device clicked through a quarter of a turn.

Dura flinched, wrapping her arms around her body. Even Hork could not help but wince as the arrow came to rest, pointing to the dark gray quadrant of the scale band. Then he exhaled heavily. "See? No harm done... In fact, nothing seems to have happened at all. And..."

"No." She shook her head. "You're wrong." She pointed. "Look..."

Hork twisted in the seat.

The walls of the chamber had turned transparent.

—

Bzya was dozing, hands loosely wrapped around the Bell's axial support pole, when the blue flashes started.

He snapped awake.

This had been a long, fruitless dive, and he had been looking forward to home, to breaking some beercake with Jool. But now something was wrong.

He scanned quickly around the cabin. Hosch, his only companion on this trip, was awake and alert; they shared a brief, interrogative glance. Bzya placed his hands gently on the polished, worn wood of the support pole. No unusual vibration. He listened to the steady hum of the great Corestuff hoops which bound about the hull of the Bell; the sound was an even thrumming, telling him that the current from the City still flowed down the cables as steadily as ever, throwing a magnetic cloak around their frail ship. He looked through the nearest of the Bell's three small windows. The Air outside — if it could be graced with the name, this far down — was a murky yellow, but bright enough to tell him that they were somewhere near the top of the underMantle. He could even see the shadow of the Spine; they were still close to its lower tip, not much more than a meter below the City...

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.