d trying to force the craft up
as far as the roof of ice would permit it to go.

"It's of no use," announced Mr. Henderson with something that sounded
like a groan. "We must prepare for the worst."

"How long can we live here without going to the surface after a fresh
supply of air?" asked Bill.

"About three days," was the answer. "I took the precaution to put a
double supply into the tanks, in readiness for an emergency, but I never
thought of such a terrible situation as this."

The submarine seemed to be moving more rapidly now. It was useless to
try to see through either the windows in the side or in the conning
tower, for all the glass was covered by the horrible bodies.

"What will they do with us when they get us where they want us?" asked
Andy.

"What can they do except hold us prisoners until--until--" The professor
broke off the sentence he dared not finish.

For an hour or more the craft was moved through the water at moderate
speed. Then it came to a stop. Those on board were alert for what might
happen next.

"I guess dey done got us in der cave," said Washington with chattering
teeth. "Now dey'll begin to devour us wid dem terrible big mouths!
Golly, I wish I was home!"

"Stop that nonsense!" exclaimed Mr. Henderson. "Be a man! There is no
danger yet. The sides of the _Porpoise_ will defy worse enemies than
those attacking us!"

At that instant the ship began to move again. It was hauled slowly
through the water.

"They are pulling us backward!" said Andy, as he watched the needle of
the compass.

Once more the submarine was stopped. Then it moved forward at a more
rapid pace than at any time since the suckers had seized it. An instant
later it brought up against some solid object with such a jar that those
inside were thrown off their feet.

"Something has hit us!" cried Jack.

"More likely we've struck something," said the professor.

Again the ship forged to the rear, and once again it was sent swiftly
ahead. Then came the second shock, harder than the first, which sent
some of the party headlong.

"They are banging us against a rock!" cried Mr. Henderson.

"Do you mean those sea suckers?"

"Yes. They have probably found that the shell of the _Porpoise_ is too
hard even for their powerful jaws. So they have taken us to some place
where the rocks show and are banging us against them in order to break
the ship, so they can get at what is inside."

Once more the ship was drawn ba