Cryptography, a system of secret writing by the late Admiral Sir Francis Beaufort, K. C. B. , adapted for telegrams, and the new half-penny postage cards.

Cryptographic table and instructions of how to use it. Published in London by Edward Stanford. The creator was Rear Admiral Sir Francis Beaufort, (1774-1857) was an Irish hydrographer and officer in the Royal Navy. The name of this table is the "Beaufort Cipher, and it is a method of encrypting text by using a series of different Caesar ciphers based on the letters of a keyword. It is a simple form of polyalphabetic substitution.

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