"Well, we'll rush things to-morrow and the next day," observed Tom as he prepared to leave the building."Then we'll soon see if it works."For the next week there were busy times in the shop near the ocean.Great secrecy was maintained, and though curiosity seekers did stroll along now and then, they received little satisfaction.At first Mr.Swift thought that the visit of Mr.Berg would have unpleasant results, for he feared that the agent would talk about the craft, of which he had so unexpectedly gotten a sight.But nothing seemed to follow from his chance inspection, and it was forgotten.
It was one evening, about a week later, that Tom was alone in the shop.The two mechanics that had been hired to help out in the rush had been let go, and the ship needed but a few adjustments to make it ready for the sea."I think I'll just take another look at the water tank valves," said Tomto himself as he prepared to enter the big compartments which received the water ballast."I want to be sure they work properly and quickly.We've got to depend on them to make us sink when we want to, and, what's more important, to rise to the surface in a hurry.I've got time enough to look them over before dad and Mr.Sharp get back."Tom entered the starboard tank by means of an emergency sliding door between the big compartments and the main part of the ship.This was closed by a worm and screw gear, and once the ship was in the water would seldom be used.
The young inventor proceeded with his task, carefully inspecting the valves by the light of a lantern he carried.The apparatus seemed to be allright, and Tom was about to leave when a peculiar noise attracted his attention.It was the sound of metal scraping on metal, and the lad's quick and well-trained ear told him it was somewhere about the ship.
He turned to leave the tank, but as he wheeled around his light flashed on a solid wall of steel back of him.The emergency outlet had been closed! He was a prisoner in the water compartment, and he knew, from past experience, that shout as he would, his voice could not be heard ten feet away.His father and Mr.Sharp, as he was aware, had gone to a nearby city for some tools, and Mr.Jackson, the engineer, was temporarily away.Mrs.Baggert, in the house, could not hear his cries.
"I'm locked in!" cried Tom aloud."The worm gear must have shut of itself.But I don't see how that could be.I've got to get out mighty soon, though, or I'll smother.This tank 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.
