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.