“But look here,” said Frank. “I have the feeling that there’s something about all this business that isn’t open and aboveboard. I, for one, vote that we do our best to find out what is going on.”

Jack sat silent for several moments.

“That isn’t what concerns me at the present moment, after all,” he said. “Whether these people with their strange plane and their secret radio are on legitimate business or not, doesn’t interest me so much. What puzzles me—and I reckon it puzzles the rest of you, too—is the design of that plane.” 18

The others nodded vigorously.

“What a tiny thing,” was Frank’s comment.

“I was busy and couldn’t see much,” supplemented Bob. “But what impressed me was her short hood. Why, she looked as if she had no engine at all.”

“That’s right,” agreed Frank. “I never saw a plane like it. And I can’t recall any designs of that nature, either. It must be a foreign-built plane, one of those little one-man things the Germans and French have been building.”

Jack shook his head, puzzled.

“There’s something strange about it,” he said, “a little thing like that, with practically no engine space. Another thing that you fellows want to remember, too, is that probably it has been flying about here for some time, yet we have never heard it. Now, down here the sound of most planes would travel far, in this quiet and secluded place, where there are no competing noises.”

“Why do you say it has been flying about here for some time?” asked Bob.