"They burst in on us in the same way," Tom explained. "But where did they come from? Where were they hiding?" "In the oil and gasoline storeroom that opens out of the motor compartment," answered Mound, the engineer. "It isn't half full, you know, and there's room for more than a dozen men in it. They must have gone in some time last night, when the airship was in the hangar, and remained hidden among the boxes and barrels until they got ready to come out and overpower us." "That's it," decided Tom. "But I don't understand how they got in. The hangar was well guarded all night." "Some of your men might have been bribed," suggested Ned. "Yes, that is so," admitted Tom, and, later, he learned that such had been the case. The foreign spies, for such they were, had managed to corrupt one of Tom's trusted employees, who had looked the other way when La Foy and his fellow-conspirators sneaked into the airship shed and secreted themselves. "Well, discussing how they got on board isn't going to do us any good now," Tom remarked ruefully. "The question is--what are we going to do?" "Bless my fountain pen!" cried Mr. Damon. "There's only one thing to do!" "What is that?" asked Ned. "Why, get out of here, call a policeman, and have these scoundrels arrested. I'll prosecute them! I'll have my lawyer on hand to see that they get the longest terms the statutes call for! Bless my pocketbook, but I will!" and Mr. Damon waxed quite indignant. "That's easier said than done," observed Tom Swift, quietly. "In the first place, it isn't going to be an easy matter to get out of here." He looked around the storeroom, which was then their prison. It was illuminated by a single electric light, which showed some boxes and barrels piled in the rear. "Nothing in them to help us get out," Tom went on, for he knew what the contents were. "Oh, we'll get out," declared Ned confidently, "but I don't believe we'll find a policeman ready to take our complaint. The upper air isn't very well patrolled as yet." "That's so," agreed Mr. Damon. "I forgot that we were in an airship. But what is to be done, Tom? We really are captives aboard our own craft." "Yes, worse luck," returned the young inventor. "I feel foolish when I think how we let them take us prisoners." "We couldn't help it," Ned commented. "They came on us too suddenly. We didn't have a chance. And they outnumbered us two to one. If they could take care of big Koku, what chance did we have?" "Very little," said Engineer Mound. "They were desperate fellows. They know something about aircraft, too. For, as soon as Koku, Ventor and I were disposed of, some of them went at the machinery as if they had been used to running it all their lives." "Oh, the foreigners are experts when it comes to craft of the air," said Captain Warner. "Well, they seem to be running her, all right," admitted the young inventor, "and at good speed, too. They have increased our running rate, if I am any judge."