"Oh, we'll have your secret all right," announced the Frenchman, his
voice harsh with triumph. "We now have the two boys who know all about
the secrets of the Pollard boats!"

"This sounds so good, I reckon we'd better go right on in, Jerry," broke
in another voice.

Gaston started, as did the two submarine boys. Then the chauffeur
leaped to the mouth of the tunnel, only to draw back in dismay as a
big form emerged and loomed up before his startled vision.

The last comer wore the dress and insignia of a petty officer of the
United States Navy.

"Get back there!" warned this big apparition, waving a warning hand that
looked big enough to be a ham. "Nobody can't go out until we look into
this cargo."

After the big sailor a smaller one crawled out of the tunnel, rising
to his feet. Though he was smaller, this second sailor was not exactly
what could have been called a little man.

"Now, then," demanded the big sailor, "whose captain of this craft?"

Gaston, his eyes threatening to bulge from his head, had fallen back
against the wall opposite. His mouth was wide open, but he ventured
no answer.

"Stow my sidelights, Jerry," muttered the big sailor to his mate,
"but this is a queer looking hold! And two young men here who'd look