“Oh, Wyn!” begged Mina Everett, “let’s go away.”

The girls had all paddled near Wyn Mallory. Now they clustered about her in plain anxiety. The boys had climbed upon the raft and all five were plainly intending to offer resistance to the ugly boatmen.

“Now, girls,” begged the captain of the Go-Aheads, firmly, “let us show some courage, at least. The boys are willing to fight our battle—”

Our battle?” gasped Bessie. “What do you mean?”

In a whisper Wyn explained to the wondering and frightened girls what it was all about.

“Polly and I believe the lost motor boat lies right beneath us here. We must keep those men off, for they are hunting for the sunken boat, too,” concluded Wynnie.

“My goodness! how exciting!” cried Grace Hedges.

“And we’ll actually win the prize your father offered us, Bess!” gasped Percy Havel.

“I don’t see that we have had much to do with it,” said Frank. “Wyn made the discovery.”

“What is for one is for all,” declared Wynnie. “But we won’t win Mr. Lavine’s prize unless the boat is raised and the silver images are delivered to Dr. Shelton. If those men get hold of the boat—”