Simple Cipher Code (1915, Woodworth)

Woodworth, H. S. (Oct. 2, 1915), "A Simple Cipher Code", Scientific American 113 (14): 291 

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A Simple Cipher Code

To the Editor of the SCIENTIFIC AMERICAN:

In the very interesting article, “Cipher Codes and Their Uses,” continued in your issue of July 3rd, I find no mention of a very simple cipher, combining simplicity in sending and receiving, with a margin of safety much higher than with other codes.

Its operation is as follows: The alphabet can be started with any letter, and with the letters either in aphabetical order or in any position desired, a code number is used, usually of four figures, although any number of figures may be used, but too many makes the code cumbersome and too few easier to decipher. The sender has a spaced rule with a cross followed by the ten digits, thus: + 1 2 3 4 5 6 7 8 9 0. The receiver has an identical rule, reversed thus: 0 9 8 7 6 5 4 3 2 1 +. We will suppose the following arrangement of letters was decided upon with two punctuations and a wordspace S T U V W X Z—, . A B C D E F G H I J K L M N O P Q R S T U V W X Y Z, the code number to be 3 4 7 9, and the message "The SCIENTIFIC AMERICAN, Woolworth Building, New York.”

The sender places the rule with the cross under the letter T, being the first letter of the message, and counts off three letters to the right, as 3 is the first figure of the code number, which brings him under the letter W; next placing the cross under H, counting off four, the next code figure he comes under letter L; continuing the next letter E, code figure 7 brings him under L. Thus the word "The" comes in cipher W L L. To show the ending of a word he places the cross under the dash; code figure gives him nine places to right or letter G. Continuing, the message would read as follows:

W L L G V G P N Q X P O L O E J P I Y R F E
U G Z S V U Z S Y, K B I A L R K R Q K E W H —
E E R V R I.

The operation of coding is simplicity itself as well as decoding, which is done in the reverse manner. The message for coding would be arranged as follows:

T H E— S C I E N T I F I C— A M E R I C A N—
3 4 7 9 3 4 7 9 3 4 7 9 3 4 7 9 3 4 7 9 3 4 7 9
W L L G V G P N Q X P O L G E J P I Y R F E U G

W O O L W O R T H — B U I L D I N G— N E W— Y O R K
3 4 7 9 3 4 7 9 3 4 7 9 3 4 7 9 3 4 7 9 3 4 7 9 3 4 7
Z S V U Z S Y . K B I A L P K R Q K E W H — E E R V R I

To decode, the arrangement would be as follows:
W L L G V G P N Q X P O L G E J P I Y R F E U G
3 4 7 9 3 4 7 9 3 4 7 9 3 4 7 9 3 4 7 9 3 4 7 9

T H E— S C I E N T I F I C— A M E R I C A N—
Z V U Z S Y . K B I A L P K R Q K E W H — E E R V R I
7 9 3 4 7 9 3 4 7 9 3 4 7 9 8 4 7 9 3 4 7 9 3 4 7 9
W O O L W O R T H— B U I L D I N G — N E W — Y O R K .

A slide rule can be used for sending or receiving, which makes the reading of a message almost as quick as if written in plain writing.

H. S. WOODWORTH. Cedar Crest, Livonia, N. Y.

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Bibliography of Cryptography: a Catalog of Books Pertaining to the Science of Codes And Cyphers. (Cincinnati, 1938)