Dura released Rauc's hand and risked a look back.

The vortex lines soared upward into the Crust, slicing through nuclear matter and embedding themselves amid the complex nuclei of the Crust material. As they entered the forest ceiling the lines thrashed with instabilities, sending bits of broken matter flying into the Air. The lines were tearing apart Qos Frenk's ceiling-farm. The crops she had tended only heartbeats earlier were now uprooted, fat wheat-stems scattered in the Air. Ironically Dura could see Crust-tree saplings, anchored by their deeper roots to the forest ceiling, surviving the spin storm where the mutated grass could not.

Further away the buildings at the heart of Frenk's farm had been torn loose of their moorings to the Crust ceiling; one of them exploded into a shower of wood splinters. Coolies and supervisors were emerging from the fields and buildings, all over the farm. They looked like a cloud of ungainly insects, dropping from the fields toward the hurtling spin lines. Even through the storm Dura could hear their shouts and cries; she wondered if the voice of Qos Frenk himself were among them. Some people squirmed desperately into the lethal rain of vorticity, as Dura and Rauc had done; but most had left it too late. Unable to squeeze through the barrage of twisting lines they were forced to turn back, to climb up toward the Crust.

But there was no haven there.

Dura saw a woman, her Air-mask still in place over her face, pull herself up into the wheat, as if burrowing into the Crust. When the vortex lines struck, her body folded around the lines, backward, her arms and legs outstretched. The woman's cries rose, thin and clear, before cutting off sharply.

Dura concentrated on the light-smell of the disturbed Air, its sharp presence in her nostrils and on her palate and lips. She wasn't out of danger yet herself. She watched an instability emerge from a line close to her. The instability grew like a tumor and scythed through the Air, its motion along the line combining with the line's upward sweep to take it diagonally past her. As it exceeded a mansheight in depth the complex grace of its waveform became distorted; it seemed to be forming a neck at its base, and secondary instabilities rippled around its circumference like attendants.

The neck began to close. Dura stared, fascinated.

The sparkling vortex line crossed itself. The throat closed, and a ring of vorticity spun clear of the line, perhaps two mansheights in diameter. The line itself, freed of its irksome instability, recoiled from the ring in a smooth surge, and then soared on toward the Crust. The ring turned in the Air, quivering, cutting a diagonal path through the array of vortex lines.

A vortex ring.