Harp frowned. "It could work. If we're lucky it could smash itself against the trunk."

The swordbird seemed bigger every second: bigger than a man, bigger than a hut-all mouth and wings and tail. The tail was a translucent membrane enclosed in a V of bone spines with serrated edges. What was it doing this far in? Swordbirds fed on creatures that fed in the drifting forests, and there were few of these, so far in toward Voy. Little enough of anything. The creature did look gaunt, Gavving thought; and there was that soft green carpet over one eye.

Fluff was a green plant parasite that grew on an animal until the animal died. It attacked humans too. Everybody got it sooner or later, some more than once. But hnmRns had the sense to stay in shadow until the fluff withered and died. Laython could be right. A head injury, sense of direction fouled up and it was meat, a mass of meat as big as the bachelors' longhut. It must be ravenous…and now it turned to face them.

An isolated mouth came toward them: an elliptical field of teeth, expanding.

Laython coiled line in frantic haste. Gavving saw Harp's line fly past him, and tearing himself out of his paralysis, he threw his own weapon.

The swordbird whipped around, impossibly fast, and snapped up Gavving's harpoon like a tidbit. Harp whooped. Gavving froze for an instant; then his toes dug into the foliage while he hauled in line. He'd hooked it.

The creature didn't try to escape: it was still fluttering toward them.

Harp's grapnel grazed its side and passed on. Harp yanked, trying to hook the beast, and missed again. He reeled in line for another try.

Gavving was armpit-deep in branchlets and cotton, toes digging deeper, hands maintaining his deathgrip on the line. With eyes on him, he continued to behave as if he wanted contact with the killer beast. He bellowed, "Harp, where can I hurt it?"

"Eye sockets, I guess."

The beast had misjudged. Its flank smashed bark from the trunk above their heads, dreadfully close. The trunk shuddered. Gavving howled in terror. Laython howled in rage and threw his grapnel ahead of it.

It grazed the swordbird's flank. Laython pulled hard on the line and sank the hardwood tines deep in flesh.

The swordbird's tail froze. Perhaps it was thinking things over, watching them with two good eyes while the wind pulled it west.

Laython's line went taut. Then Gavving's. Spine branches ripped through Gavving's inadequate toes. Then the immense mass of the beast had pulled him into the sky.

His own throat closed tight, but he heard Laython shriek. Laython too had been pulled loose.

Torn branchlets were still clenched in Gavving's toes. He looked down into the cushiony expanse of the tuft, wondering whether to let go and drop. But his line was still anchored…and wind was stronger than tide; it could blow him past the tuft, past the entire branch, out and away. Instead he crawled along the line, away from their predatorprey.

Laython wasn't retreating. He had readied his harpoon and was waiting.

The swordbird decided. Its body snapped into a curve. The serrated tail slashed effortlessly through Gavving's line. The swordbird flapped hard, making west now. Laython's line went taut; then branchlets ripped and his line pulled free. Gavving snatched for it and missed.

He might have pulled himself back to safety then, but he continued to watch.

Laython poised with spear ready, his other arm waving in circles to hold his body from turning, as the predator flapped toward him. Almost alone among the creatures of the Smoke Ring, men have no wings.

The swordbird's body snapped into a U. Its tail slashed Laython in half almost before he could move his spear. The beast's mouth snapped shut four times, and Laython was gone. Its mouth continued to work, trying to deal with Gavving's harpoon in its throat, as the wind carried it east.

The Scientist's hut was like all of Quinn Tribe's huts: live spine branches fashioned into a wickerwork cage. It was bigger than some, but there was no sense of luxury. The roof and walls were a clutter of paraphernalia stuck into the wickerwork: boards and turkey quills and red tuftberry dye for ink, tools for teaching, tools for science, and relics from the time before men left the stars.

The Scientist entered the hut with the air of a blind man. His hands were bloody to the elbows. He scraped at them with handfuls of foliage, talking under his breath. "Damn, damn drillbits. They just burrow in, no way to stop them." He looked up. "Grad?"

"Day. Who were you talking to, yourself?"

"Yes." He scrubbed at his arms ferociously, then hurled the wads of bloody foliage away from him. "Martal's dead. A drillbit burrowed into her. I probably killed her myself digging it out, but she'd have died anyway…you can't leave drillbit eggs. Have you heard about the expedition?"

"Yes. Barely. I can't get anyone to tell me anything."

The Scientist pulled a handful of foliage from the wall and tried to scrub the scalpel clean. He hadn't looked at the Grad. "What do you think?"

The Grad had come in a fury and grown yet angrier while waiting in an empty hut. He tried to keep that out of his voice. "I think the Chairman's trying to get rid of some citizens he doesn't like. What I want to know is, why me?"

"The Chairman's a fool. He thinks science could have stopped the drought."

"Then you're in trouble too?" The Grad got it then. "You blamed it on me."

The Scientist looked at him at last. The Grad thought he saw guilt there, but the eyes were steady. "I let him think you were to blame, yes. Now, there are some things I want you to have—"

Incredulous laughter was his answer. "What, more gear to carry up a hundred klomters of trunk?"

"Grad…Jeffer. What have I told you about the tree? We've studied the universe together, but the most important thing in it is the tree. Didn't I teach you that everything that lives has a way of staying near the Smoke Ring median, where there's air and water and soil?"

"Everything but trees and men."

"Integral trees have a way. I taught you."

"I…had the idea you were only guessing…Oh, I see. You're willing to bet my life."

The Scientist's eyes dropped. "I suppose I am. But if I'm right, there won't be anything left but you and the people who go with you. Jeffer, this could be nothing. You could all come back with…whatever we need: breeding turkeys, some kind of meat animal living on the trunk, I don't know—"

"But you don't think so."

"No. That's why I'm giving you these."

He pulled treasures from the spine-branch walls: a glassy rectangle a quarter meter by half a meter, flat enough to fit into a pack four boxes each the size of a child's hand. The Grad's response was a musical "O-ooh."

"You'll decide for yourself whether to tell any of the others what you're carrying. Now let's do one last drill session." The Scientist plugged a cassette into the reader screen. "You won't have much chance to study on the trunk."

PLANTS

LIFE PERVADES THE SMOKE RING BUT IS NEITHER DENSE NOR MASSIVE. IN THE FREE-FALL ENVIRONMENT PLANTS CAN SPREAD THEIR GREENERY WIDELY TO CATCH MAXIMUM SUNLIGHT AND PASSING WATER AND SOIL, WITHOUT BOTHERING ABOUT STRUCTURAL STRENGTH. WE FIND AT LEAST ONE EXCEPTION…

THESE INTEGRAL TREES GROW TO TREMENDOUS SIZE. THE PLANT FORMS A LONG TRUNK UNDER TERRIFIC TENSION, TUFTED WITH GREEN AT BOTH ENDS, STABILIZED BY THE TIDE. THEY FORM THOUSANDS OF RADIAL SPOKES CIRCLING LEVOY'S STAR. THEY GROW UP TO A HUNDRED KILOMETERS IN LENGTH, WITH UP TO A FIFTH OF A GEE IN TIDAL "GRAVITY" AT THE TUFTS AND PERPETUAL HURRICANE WINDS.

THE WINDS DERIVE FROM SIMPLE ORBITAL MECHANICS. THEY BLOW FROM THE WEST AT THE INNER TUFT AND FROM THE EAST AT THE OUTER TUFT (WHERE IN IS TOWARDS LEVOY'S STAR, AS USUAL). THE STRUCTURE BOWS TO THE WINDS, CURVING INTO A NEARLY HORIZONTAL BRANCH AT EACH END. THE FOLIAGE SIFTS FERTILIZER FROM THE WIND.