Behind them were the cook and crew of the "Dodger." Presently Hal straightened up.
"Sir," he said gravely, "I have hopes that if you test the compressed air apparatus you will find that this motor will do its share." Midshipmen and crew drew back as Jack and Eph came out of the engine room.

Lieutenant Jack had his wrench in hand, and went back to his former post.
"Young gentlemen," the commanding officer announced coolly, "we will take up, at the point where we were interrupted, the work of expelling the water from the compartments Are you ready, Mr.
Hastings ?" "Right by my post, sir," came from Hal.
The six midshipmen gathered about Benson with a stronger sense of fascination than ever.

Eph stepped past them to the stairs leading---to the little conning tower.
With steady hand Jack Benson turned the wrench.

The motor began to "mote" and there was a sense of being lifted.
"Going up!" sang Ensign Eph, with a grin.
Nor could Dan Dalzell help imitating the grin and calling out jovially: "Let me out at the top floor, please!" Having set the compressed air at work on the forward tanks, Jack Benson quickly shifted the wrench, and without a word, getting at work on the midship's compartments.

Then the stern tanks were emptied.
"May I come up, sir ?" called Dan, his voice trembling with joy, at the foot of the stairs.
"Very good," Eph sang back.