of escaping. Within two minutes it would be over, the last child would have been found among the shattered shelters and trampled into lifeless shapelessness in the bloody ground.
Within two minutes all human life on Ragnarok would be gone.
There was only one thing for him to do.
He dropped to one knee so his aim would be steady and the sights of his rifle caught the running man's back. He pressed the trigger and the rifle cracked viciously as it bucked against his shoulder.
The man spun and fell hard to the ground. He twisted, to raise himself up a little and look back, his face white and accusing and unbelieving.
"You shot me!"
Then he fell forward and lay without moving.
Prentiss turned back to face the unicorns and to look at the trees in the nearby grove. He saw what he already knew: they were young trees and too small to offer any escape for him. There was no place to run, no place to hide.
There was nothing he could do but wait; nothing he could do but stand in the blue starlight and watch the devil's herd pound toward him and think, in the last moments of his life, how swiftly and unexpectedly death could come to man on Ragnarok.
* * *
The unicorns held the Rejects prisoners in their stockade the rest of the night and all the next day. Lake had seen the shooting of the rifleman and had watched the unicorn herd kill John Prentiss and then trample the dead rifleman.
He had already given the order to build a quick series of fires around the inside of the stockade walls when the unicorns paused to tear their victims to pieces, grunting and squealing in triumph as bones crushed between their teeth and they flung the pieces to one side.
The fires were started and green wood was thrown on them, to make them smolder and smoke for as long as possible. Then the unicorns were coming on to the stockade and every person inside it went into the concealment of the shelters.
Lake had already given his last order: There would be absolute quiet until and if the unicorns left; a quiet that would be enforced with fist or club wherever necessary.
The unicorns were still outside when morning came. The fires could not be refueled; the sight of a man moving inside the stockade would bring the entire herd charging through. The hours dragged by, the smoke from the dying fires dwindled to thin streamers. The unicorns grew increasingly bolder and suspicious, crowding closer to the walls and peering through the openings between rails.
The sun was setting when one of the unicorns trumpeted; a sound different from that of the call to battle. The others threw up their heads to listen, then they turned and drifted away. Within minutes the entire herd was gone out of sight through the woods, toward the north.
Lake waited and watched until he was sure the unicorns were gone for good. Then he ordered the All Clear given and hurried to the south wall, to look down across the barren valley and hope he would not see what he expected to see.
Barber came up behind him, to sigh with relief. "That was close. It's hard to make so many people stay absolutely quiet for hour after hour. Especially the children—they don't understand."
"We'll have to leave," Lake said.
"Leave?" Barber asked. "We can make this stockade strong enough to hold out unicorns."
"Look to the south," Lake told him.
Barber did so and saw what Lake had already seen; a broad, low cloud of dust moving slowly toward them.
"Another herd of unicorns," Lake said. "John didn't know they migrated—the Dunbar Expedition wasn't here long enough to learn that. There'll be herd after herd coming through and no time for us to strengthen the walls. We'll have to leave tonight."
* * *
Preparations were made for the departure; preparations that consisted mainly of providing each person with as much in the way of food or supplies as he or she could carry. In the 1.5 gravity, that was not much.
They left when the blue star rose. They filed out through the northern gate and the rear