face went pale. She slipped quickly from the stool,
drawing in her breath with a sort of gasp. The hand that gripped the
automatic trembled a little.

"What's the matter?" Larry cried.

"I thought--" she gasped, "I think I see something in the ray! The
machine-monster is coming back!"

Her lips tightened. She lifted the little automatic and began to shoot
into the pillar of crimson fire beside the tiny, spinning globe.

Larry, watching tensely, saw a curious, bird-like something fluttering
about in the red ray, _swiftly growing larger_!

Deliberately, and pausing to aim carefully for each shot, the girl
emptied the little gun at the figure. Her body was rigid, her small
face was firmly set, though she was breathing very fast.

* * * * *

A curious numbness had come over Larry. His only physical sensations
were the quick hammering of his heart, and a parching dryness in his
throat. Terror stiffened him. Though he would not have admitted it, he
was paralyzed with fear.

The glittering thing that fluttered about in the crimson ray was not
an easy target. When the gun was empty, it seemed still unharmed. And
its wings had increased to a span of a foot.

"Too late!" Agnes gasped. "Why didn't we do _something_?"

Trembling, horror-stricken, she shrank toward Larry.

He was staring at the thing in the pillar of scarlet light.

It had dropped to the crystal disk upon which the red ray fell from
the huge, glowing tube above. It stood there, motionless except for
the swift increase of its size.

Larry gazed at it, lost in fear and wonder. It was like nothing he had
ever seen. What was it that Agnes had said, of machine-monsters, of
human brains in mechanical bodies? His brain reeled. He strained his
eyes to distinguish the monstrosity more clearly. It was veiled in
crimson flame; he could not see it distinctly.

But suddenly, when it was as tall as himself, it sprang out into the
room, toward Larry and the shuddering girl. Just off the crystal disk,
beyond the scarlet pillar of fire, it paused for long seconds, seeming
to regard them with malevolent eyes.

For the first time, Larry could see it plainly.

Its body, or its central part, was a tube of transparent crystal; an
upright cylinder, rounded at upper and lower ends. It was nearly a
foot in diameter, and four feet long. It seemed filled with a
luminous, purple liquid.

About the cylinder were three bands of greenish, gliste