Francis Bacon first mentioned the Biliteral Cypher in a brief paragraph of his book,
Advancement of Learning, published in 1605. Nineteen years later he published a book in Latin in 1624,
De Augmentis Scientiarum. In this book he detailed with illustrations how to write and use the Biliteral Cypher.
 |
| Fac-simile title page from De Augmentis, 1624 |
"The system has been recognized, and used, since the day that
De Augmentis was published, and has had its place in every translation and publication of that work since, but the ages have waited to learn that it was embedded in the original books themselves from the date of his earliest writings (1579 as now known) and infolded his secret personal history." (Elizabeth Wells Gallup,
The Bi-Literal Cypher of Sir Francis Bacon Discovered in His Works and Deciphered, p. 48).
De Augmentis Scientiarum
(The following excerpt is a translation from Francis Bacon's Latin by Gilbert Wats, 1640, including all its spelling oddities and capital letter peculiarities.)
"Wherefore let us come to C Y P H A R S. Their kinds are many, as Cyphars simple; Cyphars intermixed with
Nulloes, or non-significant characters; Cyphars of double letters under one character; wheele-cyphars; Kay-Cyphars; Cyphars of Words; Others. But the virtues of them whereby they are to be preferr'd are Three; That they be ready, and not laborious to write; that they be sure, and lie not open to deciphering; and lastly, if it be possible, that they be managed without suspicion.
 |
| Figure 1: Fac-simile from De Augmentis, 1624 |
|
"But that jealousies may be taken away, we will annexe an other invention, which, in truth, we devised in our youth, when we were at Paris; and is a thing that yet seemeth to us not worthy to be lost. It containeth the biggest degree of cypher, which is to signify
omnia per omnia, yet so as the writing infolding, may beare a quintuple proportion to the writing infolded; no other condition or restriction whatsoever is required. It shall be performed thus; First let all the letters of the alphabet, by transposition, be resolved into two letters only; for the transposition of two letters by five placings will be sufficient for 32. Differences, much more for 24, which is the number of the alphabet. The example of such an alphabet is on this wise [page] (see Figure 1). (Figure 1 illustrates the five-letter code assigned to each code letter. Figure 3 illustrates how the Bi-formed alphabet, two typefaces, are assigned to each letter of the alphabet to then obtain the "ab"-type coding seen in Figure 1.)
"Neither is it a small matter these Cypher-Characters have, and may performe: For by this
Art a way is opened, whereby a man may expresse and signifie the intentions of his minde, at any distance of place, by objects that may be presented to the eye, and accommodated to the eare; provided those objects be capable of a twofold difference onely; as by Bells, by Trumpets, by Lights and Torches, like nature. But to pursue our enterprise, when you addresse your selfe to write, resolve your inward infolded letter into this Bi-literarie Alphabet. Say the interiour Letter be
Fuge.
F = aabab.
U = baabb.
G = aabba.
E = aabaa.
 |
| Figure 2 and Figure 3: Fac-simile from De Augmentis, 1624 |
"Together with this, you must have ready at hand a Bi-formed Alphabet, which may represent all the Letters of the Common Alphabet, as well Capitall Letters as the Smaller Characters in a double forme, as may fit every mans occasion.
Now to the interiour letter, which is Biliterate, you shall fit a biformed exteriour letter, which shall answer the other, letter for letter, and afterwards let it downe. Let the exteriour example be,
Manere te volo, donec venero. (An Example of Accommodation.) FUGE = aabab.baabb.aabba.aabaa. = Manere te volo donec venero.
"We have annext likewise a more ample example of the cypher of writing
omnia per omnia: An interiour letter, which to expresse, we have made choice of a Spartan letter sent once in a Scytale or round cypher'd staffe.
"Spartan Dispatch =
All is lost. Mindarus is killed. The soldiers want food. We can neither get hence nor stay longer here.
"An exteriour letter, taken out of the first Epistle of Cicero, wherein a Spartan Letter is involved (see Figure 4).
 |
| Figure 4: Spedding, Ellis &Heath Ed. |
 |
| Figure 5: Fac-simile from De Augmentis, 1624 |
"The knowledge of Cyphering, hath drawne on with it a knowledge relative unto it, which is the knowledge of Discyphering, or of Discreting Cypher, though a man were utterly ignorant of the Alphabet of the Cypher, and the Capitulations of secrecy past between the Parties. Certainly it is an Art which requires great paines and a good witt and is (as the other was) consecrate to the Counsels of Princes: yet notwithstanding by diligent prevision it may be made unpprofitable, though, as things are, it be of great use. For if good and faithfull Cyphers were invented & practiced, many of them would delude and forestall all the Cunning of the Decypherer, which yet are very apt and easie to be read or written: but the rawnesse and unskilfulnesse of Secretaries, and Clarks in the Courts of Princes, is such, that many times the greatest matters are committed to futile and weake Cyphers."
