“That’s right,” agreed Merritt. “But what could they have been talking about? Of course, you told us about Lieutenant Duvall having leased the De Regny place for some mysterious government work. Evidently that man Dugan is there with him, and perhaps several more soldiers. But what do you suppose they are doing?”
“That was one reason why I proposed this walk this afternoon,” said Rob. “Maybe we can find out something. But I think from what Dugan said it’s pretty plain what the government is doing at the De Regny place.”
“What do you think it is, Rob?” asked Tubby interestedly.
“Testing out some sort of an airship.”
“What!”
“That’s right. Didn’t you hear the Jap speak of a Japanese aerial fleet?”
“So he did!” exclaimed Merritt. “And now I come to think of it, I remember I read some time ago that Lieutenant Duvall had invented a stability device for aeroplanes. At the time, though, I didn’t connect it with our lieutenant.”
“What we’ve got to do is to find the lieutenant and tell him about what we overheard,” said Rob decidedly. “Those fellows may succeed in their schemes, otherwise.”
“Ugh!” exclaimed Tubby, with a shudder, “I’d hate to have had that fellow Dugan grab hold of me. He’s an ugly-looking customer.”
“He is,” agreed Rob, “but we can’t help that. Our duty is clear. Why, if the Japs ever got hold of a practicable invention like that, they could send an aerial fleet across the border and demoralize the country.”