"I've thought it all out," she began. "This is what must have happened: That thief—the 'Doc,' as the gang called him—took the boat and the money the day after the bank robbery, when he woke up and found that Susie and her husband had flown away in the autogiro, and the other two were still asleep. His idea was to get out of the swamp to the St. Mary's or some other river, that would take him to the ocean."
"And get on a steamer?" demanded Dot. "But Linda, if he did that, he's out of the country by now."
"I'm not so sure of that. A canoe trip like that would take a good while—the Okefenokee is fifty miles at least from the coast. And he'd be afraid to take a train—or an automobile, for fear of being seen. Besides, I don't think he'd take a steamer right away. He'd want to go to that island first."
"In his canoe?" inquired the other, skeptically.
"No, of course not. He'd hire a motor-boat—or steal one."
"I still don't understand why he'd want to get to that island," remarked Dot.
"For two reasons," explained Linda. "One because he expected to pick up those jewels—which we have already taken away—and the other reason is that the gang has arrangements with some party that owns a steamer, to stop at the island on certain specified dates. That would be his way of getting out of the country."
"It does sound plausible," admitted Dot. "What a brain you have, Linda!"