"That will only make them suspicious."
"Yes, I guess we’d better let them go."
Still, he did not give up the attempt just then, opening the throttle so that the Sleuth was racing along at top speed. But the other boat had the advantage, and cut across their course with a quarter of a mile to spare. Joe gazed through the binoculars, striving to identify the two men.
"No use," he remarked, at last. "The fellow at the wheel is turned away from us, and the other man is bending down in the boat so I can't see his face."
"Is it the same boat?"
"I can't be positive. But I think so. It certainly looks very much like it."
"I'm almost sure. Of course, there might be lots of other motorboats just like it—but I've got a hunch that it's the same craft."
"What would it be doing at Blacksnake Island? There's no doubt that it came from there."
"That's for us to find out. We'll let them go on to the mainland. Then we'll circle back and go up the other side of the island."
In a short time the other craft disappeared from view, entering a small cove some distance down the coast, and Frank turned their boat about and headed toward Blacksnake Island again. They approached it from the seaward
