he man beside them spoke quickly. "One moment--you will pardon
me--someone is calling--" He listened intently to some soundless call,
and he sent a silent message in reply.

"I have instructed them," he said. "Come and you shall see how
impregnable is our position. The red ones have resented our
destruction of their ship."

The face of the girl, Althora, was perturbed. "More killings?" she
asked.

"Only as they force themselves to their own death," her brother told
her. "Be not disturbed."

* * * * *

The throng in the vast space drew apart as the figure of their leader
strode quickly through with the two men following close. There were
many rooms and passages; the men had glimpses of living quarters, of
places where machinery made soft whirring sounds; more sights than
their eyes could see or their minds comprehend. They came at last to
an open chamber.

The men looked up to see above them a tremendous inverted-cone, and
there was the gold of cloudland glowing through an opening at the top.
It was the inside of a volcano where they stood, and McGuire
remembered the island and its volcanic peak where the ship had swerved
aside. He felt that he knew now where they were.

Above them, a flash of light marked the passage of a ship over the
crater's mouth, and he realized that the ships of the reds were not
avoiding the island now. Did it mean an attack? And how could these
new friends meet it?

Before them on the level volcanic floor were great machines that came
suddenly to life, and their roar rose to a thunder of violence, while,
in the center, a cluster of electric sparks like whirling stars formed
a cloud of blue fire. It grew, and its hissing, crackling length
reached upward to a fine-drawn point that touched the opening above.

"Follow!" commanded their leader and went rapidly before them where a
passage wound and twisted to bring them at last to the light of day.

The flame of the golden clouds was above them in the midday sky, and
beneath it were scores of ships that swept in formations through the
air.

"Attacking?" asked the lieutenant with ill-concealed excitement.

"I fear so. They tried to gas us some centuries ago; it may be they
have forgotten what we taught them then."

* * * * *

One squadron came downward and swept with inconceivable speed over a
portion of the island that stretched below. The men were a short
distance up on