TheCodeBreakers
time to point a pistol at the captain and stop him from throwing
overboard most of the ship's secret papers. Among them was the Allied
Merchant Ships' Code, a two-part code issued by the Admiralty for
messages via the Broadcasting for Allied Merchant Ships, or BAMS,
commonly called the "BAMS code."
Also recovered were several superencipherment tables, though not the
current ones. Atlantis, however, had aboard in her special crew a wireless
operator named Wesemann who had served for three years in one of the
German cryptanalytic services. Wesemann achieved what might be the
first nautical cryptanalysis on record when, on the basis of the captured
code and several merchant messages that he had intercepted, he
succeeded in reconstructing about one third of the superencipherment
table then in use. As a result, Atlantis could read much of the Allied
merchantmen's traffic and could await her victims at likely spots.
annaabi.ee 
