Stamps Sending A Secret Message

Here is an interesting article that mentions the part played by Mexican and Cuban postage stamps in Fidel Castro's plan to overthrow the Cuban government:

https://www.wilsoncenter.org/public...r-revolution

Hey 22crows, that was a very interesting story and even though I have done research on the Castro revolution I hadn't realized that they were using stamps on their mail as a message communications device. I suppose beside different stamps that they could turn the stamps at different angles and use placement on the envelope which could tell the whole story to the recipient without even needing to read the letters contents.

Reminds me of when Baden Powell was a spy and drew maps on the backs of postage stamps before affixing them to the envelopes to fool the censors who were checking his mail.
Some one should do a book on philatelic espionage, that would be an interesting read.