“Rod was always up to tricks like that,” said Hiram. “He would play them on board the ships we sailed in. I think he had some Italian blood in him, for once, when we were at an Italian port, he was as much at home as any of the natives, and he could talk their lingo, too. But I didn’t know him in his false beard and wig. He was always smooth-shaven.”
“It wasn’t a false beard nor wig, either,” said Bob. “He just let his hair and whiskers grow. He was clean shaved when he and the man with the iron hook took the milk train. Well, we’ll let them go. They don’t figure in this mystery any more.”
“Unless they’ve already dug up the treasure and skipped out with it,” suggested Ned.
“It couldn’t have been done,” declared Bob. “Rod was only digging at random in the bramble patch, though why he hit on that is more than I can tell. But we’d better get to work on this.”
“I’ll say you had!” exclaimed Harry. “And there’s a long trail ahead of you—a long, long trail.”
However, Bob Dexter went to work with a certain system in mind. He had made a sort of study of puzzles, ciphers and the like, and knew certain fundamental rules governing them. That the secret of the treasure was a comparatively simple one he felt convinced.
“One of the things to do is to see if this paper contains any secret writing,” he said. “I mean certain words may be written in with a chemical so as to remain invisible until heated or treated with other chemicals.
“Now Mr. Denby wouldn’t be very likely to make a complicated affair—one that would need other chemicals to bring out the writing. He would know that Mr. Beegle, here, couldn’t have such chemicals at hand. Consequently the simplest way would be the one he would select—that is heat. Let’s see if, like the cipher in Poe’s ‘Gold Bug,’ heat will bring out anything.”
They held the parchment near the flame of a candle, but aside from producing rather an unpleasant odor, nothing developed. The writing remained the same.
“The next thing,” said Bob, “is to pick out from this mass of words certain ones that mean something. As it stands it might be just part of an essay on astronomy or geography. Now in ciphers of this kind certain key words are used, say beginning with the second or third from the start of the message, and then letting the words follow in a certain numerical sequence. Let’s try that.”