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tter against America. It was he who talked about the wonder-workers and the necessity for haste. I never heard Frederic say anything--anything disloyal, that is."
"The fact that he knew enough to keep his mouth closed shows that he is the more intelligent of the two. Don't forget, too, that at times he even dared to don the uniform of a British officer. You saw him yourself. Undoubtedly he is the more dangerous of the pair."
"But who read these advertisements?" asked Jane, seeking to change the subject. "For whom were the bulletins intended?"
"It was one of their ways of keeping in communication with their thousands of secret agents all over this country. I wouldn't be surprised if occasionally these advertisements were printed in Texas papers and shipped over the border into Mexico. We have been watching the mails and the telephone and telegraph lines for months, yet all the while Mexico has been sending messages across, telling the U-boats everything they needed to know. We never thought of checking up the advertising in papers in the Mexican mail."
"But what about the messages old Mr. Hoff left in the bookstores? Was that part of the plan, too?"
"It may have been simply a duplicate method of communication in case the other failed. The Germans here know that they are constantly watched and take every precaution. We'll land that girl as soon as we have the Hoffs safe behind the bars, and then we'll soon see if Carter's dachshund theory was right."
"But who," asked Jane, "is the spy in our navy? Who signalled the Hoffs' apartment and supplied them with the news about our transports? Was it Lieutenant Kramer?"
"Probably," said Chief Fleck carelessly, "that is not my end of the work. It is up to the Naval Intelligence Bureau to clean out the spies in the navy. I'm after the boss-spy. After we land him it will be easier to get the small fry. A defiant German prisoner once boasted to me that Germany had a man on every American ship, in every American regiment, and in e