rise, he heard the other
octopus crawling up the connecting ramp, coming to see what had
befallen its fellow. Preceded by two trembling guns, McKegnie tiptoed
to the ramp and peered down.

From the darkness he saw another complicated mass of metal tentacles
and glass advancing up towards him. Fear smote the cook, and almost
without volition be pointed his guns and pulled the triggers. As
before, a bullet crashed into the great dome of glass, and he watched
a short but terrible death struggle. He had, by himself, slain two
octopi!

A tremendous elation filled McKegnie--until it occurred to him that
his shots might have been heard outside. At once he ran and looked at
the teleview view screen, and what he saw on its silver surface took
all the triumph abruptly out of him. The octopi outside were darting
about with alarming activity; a whole cluster of them was centered at
the exit port, and, even as the cook stared, the preliminary sounds of
opening it came to his ears.

"Now I _got_ to run this ship!" he groaned.

* * * * *

He peered at the mass of levers and wheels, put out a hand, closed his
eyes, hesitated, and pulled one of them back. Nothing happened.

He tried another. The noise below grew, but still the _NX-1_ remained
motionless. Desperate, the cook jerked several other levers. The whine
of electric motors surged through the silence; the submarine shuddered
and slewed off to the right, as if trying to dig into the sea-floor.

"I got it started!" he cried. He did something else. The _NX-1_ stuck
her bow dizzily up and sped into the misty-blue realm above in a
grand, sweeping circle. The sea-floor with its mound-buildings and
swarming octopi fell away behind with a rush.

"There!" muttered the triumphant cook. "But--how did I do it?"

The submarine was rising like a sky-rocket. McKegnie remembered
suddenly that Wells had said the cavern was only a few miles high; he
must now be very near the top. He held his breath while he pushed a
likely looking lever the other way.

He was lucky. The _NX-1_ capered like a two-year-old, kicked up her
stern and bolted eagerly for the depths once more. Again the floor of
the cavern rushed up at him, again he pulled the potent lever back,
and again the submarine meteored upward.

This procedure went on for some time. McKegnie was only running an
elevator. Was he doomed to dash up and down between floor and ceiling
forever? He gave forth