om the cavern projected twisting tentacles of
gargantuan dimensions, and red eyes, thirty feet in diameter, glared
balefully at them. For several minutes the light of the submarine played
across the mouth of the cave, and then the floodlights on the cliff
sprang into full glow and bathed the ball and the mouth of the tunnel in
a flood of light.

Before their horrified gaze was an octopus of a size to make them
disbelieve their eyes. The submarine had moved up to within a few feet
of them, and the light from it played full on the ball. The submarine
maneuvered in the vicinity, keeping the ball full in the beam of its
light, and then drew back. As it did so, the floodlights on the cliff
died out and the beam of the submarine's light was directed away from
them. Dr. Bird jumped to the telephone.

"Head straight out to sea and full speed ahead!" he shouted. "Don't try
to pull us in; tow us!"

* * * * *

The ball swayed as the _Minneconsin's_ mighty engines responded to his
orders and the cliff wall disappeared.

"As long as they know we're here, we might as well announce our presence
in good style," said the doctor grimly as he closed a switch and threw
all of the sphere's huge lights into action. He had turned on the lights
just in time, for even as he did so a mighty tentacle shot out of the
darkness and wrapped itself around the ball. For a moment it clung there
and then was withdrawn.

"The thing can't stand light," remarked the doctor as he threw off the
switch. "That sub was herding it like a cow by the use of a light beam.
As long as we are lighted up we are safe from attack."

"Then for God's sake turn on the lights!" cried Carnes.

"I want it to attack us," replied the doctor calmly. "We have no
offensive weapons and only by meeting an attack can we harm the thing."

As he spoke there came a soft whisper of sound from the vitrilene walls
and they were thrown from their feet by a sudden jerk. Dr. Bird stumbled
to the switch and closed it, and the ball was flooded with light. Two
arms were now on them but they were slowly withdrawn as the lights
glared forth. The huge outlines of the beast could be seen as it
followed them toward the surface. Its great eyes glared at them
hungrily. The submarine was visible only as a speck of light in the
distance.

* * * * *

The _Minneconsin's_ speed was picking up under the urge of her huge
steam turbines,