Franz von Rintelen Captain Franz Dagobert Johannes von Rintelen ( 1877 – 30 May 1949 ) was a German Naval Intelligence officer in the United States during World War I . He came from a banking family with good connections in American banking , having served with " Deutsche Bank " as well as acting as U . S . representative for " Disconto - Gesellschaft " , then Germany ' s number two bank , beginning in 1906 . He also spoke excellent English . He was sent to the still - neutral United States in 1915 , at age 38 , on a false Swiss passport in the name of Emil V . Gasche ( the surname appropriated from his brother - in - law ) . Arriving on 3 April , Captain von Rintelen operated independently and received his funds and instructions directly from Berlin . His mission was to sabotage American ships carrying munitions and supplies to the Allies . Arriving in New York City , he posed as businessman Frederick Hansen and , with Heinrich Albert , set up a dummy corporation called Bridgeport Projectile Company , through which he purchased gunpowder , which he then destroyed . The goal was to create shortages of smokeless powder on the American market which was to prevent the Entente from purchasing munitions . He also set up another company , the Austrian - subsidized Transatlantic Trust Company at 57 William Street in Manhattan , where he had deposited a large amount of money on his arrival from Germany . He also attempted to buy the du Pont powder factory , without success . Von Rintelen worked with a chemist , Dr . Scheele , to develop time - delayed incendiary devices known as pencil bomb s , which were then placed in the holds of American merchant ships to cause fires in the ships ' holds so that the crew would throw the munitions overboard . Several were planted successfully . He also organized the Labor ' s National Peace Council to foster strikes and work slowdowns among munitions workers to inhibit American aid to the Allies . From offices at 55 Liberty Street in New York City ( around the corner from Transatlantic Trust , where he was Hansen ) , he spent US $ 500 , 000 doing so , most of which went to his U . S . agent , David Lamar ; known as the " Wolf of Wall Street " , Lamar ' s reports of success were exaggerated . During 1915 , he negotiated with Victoriano Huerta for money to purchase weapons and U - boat landings to provide support , while hoping to persuade Mexico to make war on the U . S . , which Germany hoped would end munitions supplies to the Allies . Their meetings , held at the Manhattan Hotel ( as well as another New York hotel , " probably the Holland House " at Fifth Avenue and 30th Street ) were observed by Secret Servicemen , and von Rintelen ' s telephone conversations were routinely intercepted and recorded . It is probable Room 40 , which could read at least two of the cipher s he used , was also recording von Rintelen ' s activities . His work was largely successful and probably included some part in the Black Tom explosion in 1916 . Also in 1915 he bought ammunition and supplied money to the deposed Mexican dictator Huerta and encouraged him to try to seize back power in Mexico . His colleagues were not all pleased with his success , and Franz von Papen ( later Chancellor of Germany ) sent a telegram to Berlin complaining about him . The telegram was intercepted and decrypted by Room 40 . He received a telegram , ostensibly from his Admiralty ( in a cypher Room 40 could read ; it remains unclear if Room 40 originated it , or merely intercepted it ) , and sailed back to Germany on 3 August , on the neutral Holland America liner " Noordam " . He was captured at Southampton , England , and protested his innocence so convincingly , both the Swiss Minister in London and Scotland Yard were persuaded . At a further meeting , the head of Room 40 , Admiral W . R . " Blinker " Hall , was not , and von Rintelen confessed ; he was imprisoned in Britain for twenty - one months , then interned in Atlanta , Georgia for three years , after the U . S . entered the war . He returned to Germany in 1920 , a forgotten man . He moved to England , where he died on 30 May 1949 . Von Rintelen wrote " The Dark Invader : War - Time Reminiscences Of A German Naval Intelligence Officer " which was published in 1933 . The scanned version of the original Penguin Books 1933 edition is available on line at Project Gutenberg Australia http : / / gutenberg . net . au / plusfifty - n - z . html