Talk:The Alphabet Cipher

The actual text of Carroll's article should probably reside at Wikisource (http://sources.wikipedia.org/wiki/Main_Page:English). See Don't include copies of primary sources. &mdash; Matt


 * I'm okay either way. It's actually a good description of Vigenere that I recommend in that article, but the fact that we have Wikisource means that in general we could count on it not going anywhere.  Lunkwill 17:03, 14 May 2004 (UTC)

Hello, but the following information currently in the article is a exact word-for-word copy of text from at least two books (the original) and the book "A Book of Puzzlements" by Herbert Kohl, copyright 1981. Pages 211 and 212 state that the following is a direct quote from Carroll's original:

"EACH column of this table forms a dictionary of symbols representing the alphabet: thus, in the A column, the symbol is the same as the letter represented; in the B column, A is represented by B, B by C, and so on.

To use the table, some word or sentence should be agreed on by two correspondents. This may be called the `key-word', or `key-sentence', and should be carried in the memory only.

In sending a message, write the key-word over it, letter for letter, repeating it as often as may be necessary: the letters of the key-word will indicate which column is to be used in translating each letter of the message, the sy mbols for which should be written underneath: then copy out the symbols only, and destroy the first paper. It will now be impossible for any one, ignorant of the key-word, to decipher the message, even with the help of the table.

For example, let the key-word be vigilance, and the message `meet me on Tuesday evening at seven', the first paper will read as follows --

v i g i l a n c e v i g i l a n c e v i g i l a n c e v i m e e t m e o n t u e s d a y e v e n i n g a t s e v e n h m k b x e b p x p m y l l y r x i i q t o l t f g z z v

The second will contain only 'h m k b x e b p x p m y l l y r x i i q t o l t f g z z v'.

The receiver of the message can, by the same process, retranslate it into English.

N.B. &mdash; If this table be lost, it can easily be written out from memory, by observing that the first symbol in each column is the same as the letter naming the column, and that they are continued downwards in alphabetical order. Of course it would only be necessary to write out the particular columns required by the key-word: such a paper, however, should not be preserved, as it would afford means for discovering the key-word."

PROBLEMS:

1. There are no indications in the article that these are the quoted words of Carroll.

2. This may violate the copyright of the 1981 above mentioned book.