mile, then
stopped. In the light of the ship's windows, they could see the faint
mistiness of the inconceivably hard, artificial matter, and beyond the
slick, polished surface of the rock it was pushing aside. The cone shape
was still there.

There was a terrific roar behind them, the rock above cracked, shifted
and moved about.

"Raying the spot where we went down," Arcot grinned happily.

The cone and cylinder merged, shifted together, and became a sphere. The
sphere elongated upward and the _Ancient Mariner_ turned in it, till it,
too, pointed upward. The sphere became an ellipsoid.

Suddenly the ship was moving, accelerating terrifically. It plowed
through the solid rock, and up--into a burst of light. They were
_inside_ the dome. Great ships were berthed about the floor. Huge
machines bulked here and there--barracks for men--everything.

The ellipsoid shrank to a sphere, the sphere grew a protuberance which
separated and became a single bar-like cylinder. The cylinder turned,
and drove through the great dome wall. A little hole but it whirled
rapidly around, sliced the top off neatly and quickly. Again, like a
gigantic teapot lid, the whole great structure lifted, settled, and
stayed there. Men, scrambling wildly toward ships, suddenly stopped,
seemed to blur and their features ran together horribly. They fell--and
were dead in an instant as the air disappeared. In another instant they
were solid blocks of ice, for the temperature was below the freezing
point of carbon dioxide.

The giant tamper set to work. The Thessian ships went first. They were
all crumpled, battered wrecks in a few seconds of work of the terrible
disc.

The dome was destroyed. Arcot tried something else. He put on his
control machine the equation of a hyperboloid of two branches, and
changed the constants gradually till the two branches came close. Then
he forced them against each other. Instantly they fought, fought
terribly for existence. A tremendous blast of light and heat exploded
into being. The energy of two tons of lead attempted to maintain those
two branches. It was not, fortunately, explosive, and it took place over
a relux floor. Most of the energy escaped into space. The vast flood of
light was visible on Venus, despite the clouds.

But it fused most of Antarctica. It destroyed the last traces of the
camp in Antarctica.

"Well--the Squadron was wiped out, I see." Arcot's voice was flat as he
spoke. The Squadron: twenty