"In the First Edition of his work "The Two Bookes of Francis Bacon, of the proficience and advancement of Learning, divine and humane" published at London in 1605, the Author only alludes briefly to his Bi-literal Cipher. Speaking of Ciphers generally (Booke II) he says:
"But the vertues of them, whereby they are to be preferred, are three; that they be not laborious to write and reade; that they bee impossible to discypher; and in some cases, that they bee without suspicion. The highest Degree whereof, is to write OMNIA PER OMNIA; which is undoubtedly possible, with a proportion Quintuple at most, of the writing infoulding, to the writing infoulded, and no other restrainte whatsoever."
It was not till eighteen years later that he gave to the public an explanation of this 'infoulding' writing. In the rarely beautiful edition of the work in Latin printed in London by Haviland in 1623, the passage relating to secret writing is much amplified. Indeed the entire work is completed in many ways and greatly enlarged as is shown by its title.
"De Dignitate et Augmentis Scientiarum. Libros IX."
The following is his revised statement:
"Ut vero suspicio omnis absit, aliud Juventum subijciemus, quod certe, cum Adolescentuli essemus Parisiis, excogitavimus; nee etiam adhuc visa vobis res digna est, quae pereat. Habet enim gradum Ciphrae altissimum; nimirum ut Omnia per Omnia significari possint: ita tamen, ut Scriptis quae involuitut, quintuplo minor sit, quam ea cui involvatur: Alia nulla omnino