TheCodeBreakers
lead to severe penalties for the users.
The third kind of open code is the geometrical. A Cardano grille places
the message-bearing words in fixed positions on a page. The significant
words can be placed at intersections of the lines of a geometrical diagram
of specified dimensions. In the 1600s, Sir John Trevanion, a Cavalier
awaiting trial and almost certain execution by Cromwell's forces, noted
the third letter after each punctuation mark in a letter that his jailers
had scrutinized before giving him arid learned that Panel at east end of
chapel slides. He disappeared during vespers. And in World War II,
captured U-boat officers spelled out secret messages in their letters home
by breaking the flow of script after each significant letter. An alert censor
noticed that the minute gaps did not occur in natural places, as after
syllables. The hidden messages described Allied anti-submarine tactics
and technical U-boat faults
annaabi.ee 
