“Not at all.  Hugo Schmidt, who was reputed to be the paymaster of the gang, was caught trying to burn a copy of this code at the German Club.  With the records of their wireless messages our government managed to reconstruct the whole code.  The use of a word or two from this code in these advertisements is most significant.  It shows that whoever prepared these advertisements was high in the confidence of the German government.  Only the very topnotch spies are likely to be permitted to know the diplomatic code.”

“And you think, then, that Otto Hoff may be the head of the conspirators in this country?” said Jane.

“Not Otto—­Frederic,” said Fleck quickly.  “The young man, I am certain, was the director, probably sent out from Berlin after the country became too hot for Von Papen and Boy-ed.  The old man, I believe, merely carried out his orders.  I doubt even if they are uncle and nephew.”

“I think you are wrong about that,” protested Jane.  “Whenever I was listening over the dictograph it was always the old man who was so bitter 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 every department in Washington.  I suspect it comes pretty near being true.  A country that has so many citizens with German names and such an enormous population of German descent has its hands full.”