but she didn't complain. Gradually the
forest became mostly trees again. They found a path some animal had
made and followed it.

When they came to the clearing, Nelson almost didn't see the thing in
the air. He heard Glynnis gasp behind him, and with a start, glanced
around. She was staring at something in front of them, and in the air.
He looked where she was staring and saw the air robot hovering near
the edge of the clearing. It was about two feet long, slender,
metallic and smooth. Nelson knew though that it was alert and that
receptors built into its skin were registering their presence. It
hovered about ten feet above the ground, some twenty feet from them,
making no noise. Sky robots made noise only when they were moving at
a fairly good speed. They had fled the noise of one only to be trapped
in the silence of another.

Suddenly, Glynnis was shouting, "It's one of them!" Nelson turned to
see her level her gun, and before he could stop her a white hot
streamer lashed out at the robot and engulfed it.

"No," he shouted, too late. The machine took the blast turning cherry
red and bobbing lightly in the air for a moment before energy
compensators and stabilizers adjusted to the effects of the blast. The
machine turned back to its lustrous silver color and there was a low
hum as it righted itself gracefully then swung around, into the center
of the clearing to get a better focus on them.

"It doesn't even have a mark on it," Glynnis said, in a low tone,
moving closer to Nelson and laying one hand on his shoulder.

"No. But don't worry; it can't hurt us. We've got to figure some way
to get out of here and leave it behind." He turned and gently guided
her toward the trees. When they were in the dubious shelter of the
trees, Nelson stopped and tried to figure a way out. He could see the
machine hanging in the center of the clearing on invisible lines of
force, turning slightly to find them in the dense growth, then, with
one end pointed at them, bobbing slightly with the low breeze.

"What's it doing?" Glynnis asked. There was superstitious awe in her
voice that annoyed Nelson.

"Sending a signal to the patrol. We don't have much time before they
get here."

"But if the machine can't be shot down what can we do?"

"Hand me your gun." He took her gun and pointed to a vernier control
set into the side of the weapon. "This is the intensity control; it's
on low." He turned it up. "Now it's on full."

"Will th