is airtight, and it won't take me long to breath up all the
oxygen there is here. I must get that slide open."

He sought to grasp the steel plate that closed the
emergency opening. His fingers slipped over the smooth,
polished surface. He was hermetically sealed up--a captive!
Blankly he set his lantern down and leaned hopelessly
against the wall of the tank.

"I've got to get out," he murmured.

As if in answer to him he heard a voice on the outside,
crying:

"There, Tom Swift! I guess I've gotten even with you now!
Maybe next time you won't take a reward away from me, and
lick me into the bargain. I've got you shut up good and
tight, and you'll stay there until I get ready to let you
out."

"Andy Foger!" gasped Tom. "Andy Foger sneaked in here and
turned the gear. But how did he get to this part of the
coast? Andy Foger, you let me out!" shouted the young
inventor; and as Andy's mocking laugh came to him faintly
through the steel sides of the submarine, the imprisoned lad
beat desperately with his hands on the smooth sides of the
tank, vainly wondering how his enemy had discovered him.