Early manual and mechanical cryptography - Cryptography: Cracking Codes - page 53

Used in the field by the U.S. Army Signal Corps at the beginning of
World War I, the disk enabled messages to be quickly encrypted with
a simple substitution cipher by rotating the inner ring. Encyclopædia
Britannica, Inc.
after enciphering three or four words, thus conceiv-
ing of the notion of polyalphabeticity. This same device
was used almost five centuries later by the U.S. Army
Signal Corps for tactical communications in World War
I. Giambattista della Porta provided a modified form
of a square encryption/decryption table and the earliest
example of a digraphic cipher in De furtivis literarum notis
(1563; “The Notorious Secret Literature”). The Traicté des
chiffres (“Treatise on Ciphers”), published in 1586 by Blaise
de Vigenère, contains the square encryption/decryption