A letter for you
Someone has sent you a letter in cipher
How the keys work
Each key is the one rebuilt from the original documents and published with its write-up. The site reads the same key files the decoders use, so a letter written here deciphers with the historical key.
- García de Toledo to Philip II, 1565: two-digit figures from 12 to 43, in alphabetical order, with a choice of figures for the common letters. Letters the key lacks are folded as a Spanish clerk would (v to u, j to i), and a w, which none of the older keys has, is written as a double u and read back as w.
- Richelieu to Rancé, 1629: figures with three to five choices for each vowel, single figures for de and la, and numbers for great names. Try le roi, Monsieur or l'Espagne.
- Armstrong to Madison, 1808: a numbered code of 571 words, syllables and letters, rebuilt from the State Department's pencil decodes. Words the code lacks are spelt from syllables. A few letters (h, j, l, q, r, u) have no group of their own, and a word that cannot be built is left in clear, as the clerks did.
- Needham to Walsingham, 1587: a three-grid pigpen with plain, dotted-below and dotted-inside boxes. The letter values are those of the key rebuilt from Harley 287 f. 39v. The box shapes are drawn in textbook grid form, not traced from the leaf.
Homophonic keys give the writer a choice of figures for the same letter; the page picks at random, so the same message comes out differently each time. The Sun Yat-sen telegraph code is not offered, because it enciphers Chinese characters, and the invented signs of the sixteenth-century French ciphers are not, because the site keeps them as names rather than drawings.