ne scream that broke
like brittle steel in the same instant that it began.

Dean found the big casting in the circle of his glass. There were
black figures moving near it; they were indistinct. He changed the
focus--they were gone before he could get their images sharp.

But the casting! Plainly he saw its great bulk that many men had
worked to ease down to the sand. It was outlined clearly now until its
edge became a blur, until the sand rolled in upon it, and its black
mass became a circle that shrank and shrank and vanished utterly at
the last.

"It's gone!" Rawson shouted. "It sank into the sand! I saw it...."

He was running for the car. A clamor of voices was coming from below;
the sound died under the thunder of the car's exhaust as Rawson gave
it the gun and sent the big machine leaping toward the waiting curves.

CHAPTER V

_The Attack_

Every light of the camp was on as Rawson and his assistant approached.
A shallow depression in the sand marked the place where the big
casting had been. Beyond it a hundred feet was a black swarm of men
that parted as the car drew near. They had been gathered about a
figure upon the sand.

Dean sensed something peculiar about that figure as the big car
ploughed to a stop. He leaped out and ran forward.

He knew it was Riley there on the ground, knew it while still he was a
score of feet away. Only when he was close, however, did he realize
that the body ended in two stubs of legs; only when he leaned above
him did he know that the Irish foreman's big frame had been cut in two
as if by a knife.

The severed legs lay a short distance beyond the body; they had fallen
side by side in horrible awkwardness, their stumps of flesh protruding
from charred clothing--and suddenly, shockingly, Rawson knew that the
flesh of body and legs had been seared. The knife had been hot--its
blade had been forged of flame!

He heard Smithy cursing softly, unconsciously, at his side.

"The green light," Smithy was saying in horrified understanding. "But
who did it? How did they do it? Where did they go?"

"Quiet!" ordered Rawson sharply. He dropped to his knees beside the
mutilated body. Riley's eyes had opened in a sudden movement of
consciousness.

* * * * *

The voice that came from his lips was a ghastly whisper at first, but
in that stricken thing that had been the body of Riley, foreman of the
night drilling crew, some reservoir of stren