on top of it.
He went inside the laboratory. "I may as well tell you, Cliff. I
wouldn't have brought Susie if I'd thought the experiment had the
least chance of success," he said.

Cliff said nothing. He was bending over the wheel, adjusting a
micrometer. "All ready, Kay?" he asked.

* * * * *

Kay nodded and stepped back. He swallowed hard. He hated sacrificing
Susie to the cause of science; he almost hoped the experiment would
fail.

Cliff pressed a lever, and slowly the ponderous top began to revolve
upon its axis. Faster, faster, till it was nothing but a blur. Faster
yet, until only its outlines were visible. Cliff pressed a lever on
the other side.

Nothing happened apparently, except for a cloudy appearance of the air
at the open end of the laboratory. Cliff touched a foot lever. The top
began to grow visible, its rotations could be seen; it ran slower,
began to come to a stop.

The cloud was gone. Where the airplanes and other junk had been, was
nothing but a heap of grayish dust. It was this that had made the
cloud.

Nothing remained, except that impalpable powder against the background
of the trees.

Kay caught Cliff's arm. "Look out!" he shouted, pointing to the heap.
"Something's moving in there!"

Something was. A very angry lady porcupine was scrambling out, a
_quillless_ porcupine, with a white skin, looking like nothing so much
as a large, hairless rat. Cliff turned to Kay.

"We've failed," he said briefly. "Too late for this year now."

"But--the quills?"

"Inorganic material. But even the bones remain intact because there's
circulation in the marrow, you see. And the Earth Giants haven't even
bones. They're safe--this year!"

He flung himself down under a tree, staring up at the sky in abject
despair.

* * * * *

"Look, Kay, I've got my number!" Ruth Meade smiled as she handed Kay
the ticket issued by the Government announcing the lottery number
provided for each citizen.

One hundred thousand young people between the ages of fifteen and
twenty would be drawn for the sacrifice, and Ruth, being nineteen, had
come within the limits, but this would be her last year. In a few
weeks the Government would announce the numbers--drawn by a second
lottery--of those who were condemned.

Then, before these had been made public, the victims would already
have been seized and hurried to the airship depots in a hundred
places, fo