As Elizabeth Bruxer correctly identified within a few short hours of its posting, this month’s crocodile mystery showed the inner disc of an unconstructed volvelle from a copy of the 1591 edition of Giambattista della Porta’s De furtivis literarum notis (STC 20118). The key to her identification lay in recognizing the image as being part of a volvelle and guessing that it was connected to ciphers. (Read her comment for a full elucidation of how she solved the mystery.)
What I showed you last week was just one inner disc, although the “3” written below it might have clued you in that there were other similar objects. A view of the full page opening makes it more clear, I think, what we’re looking at:
There, in the upper right-hand corner is our disc number 3, along with a nearly identical disc labeled “1” and at the bottom of the page, disc 2. Why would these discs be numbered? So that the person constructing the volvelles knows which frame they belong to:
These images are from the first of the Folger’s two copies of STC 20118. The second copy’s volvelles are also unconstructed, but its sheet of inner discs is bound in differently:
The English edition of Porta’s De furtivis actually exists in two states. The version that we’ve been looking at, printed in London by John Wolfe in 1591, states that information in the imprint on its title page: “Cum priuilegio Londini, apud Iohannem Wolphium, 1591” (STC 20118). A second state of this edition carries the false imprint of “Cum priuilegio Neapoli, apud Ioa. Mariam Scotum, MDLXIII” (STC 20118a). The Folger also has a copy of that state, but there the volvelles have been finished:
I’ve written about volvelles before, because they’re amazing, but what I wanted to share in this post is the equally interesting process of their making. Volvelles, with their lovely and fragile movable parts, don’t appear magically in books, of course, but require additional steps in the book-making process to produce. Porta’s De furtivis gives us one peek into this process.
Another glimpse comes from the Folger’s copy of Claude Dariot’s 1557 Ad astrorum judicia facilis introductio, which relies heavily on volvelles to explain astrology. This copy of the first edition of his work, however, is still awaiting for its volvelles to be assembled. While the frames are in place, the moving parts are printed on a single sheet that is bound in, along with instructions, in the back of the book:
While the first sheet of movable parts we looked at has been bound in to its book in such a way that it looks part of the finished product (the discs are oriented the same way as the rest of the book; the edges of the sheet align with the edges of the rest of the book’s leaves), this copy of Dariot is clearly unfinished—you can’t even open up the sheet of movable parts all the way. Given the water stains that run throughout the book, perhaps it survived in this state because it was set aside and forgotten.
What I find so interesting about these unfinished constructions is how much they drive home the labor that would be involved in making them. A finished volvelle makes me want to turn it; it doesn’t necessarily make me think about the many steps necessary for putting it together. But there are tiny pieces to be cut out and sewn in, by hand, in each copy that requires it. (Some owners, obviously, don’t bother with that final step, but that raises the question of how they were using their books. If the volvelles are there to help convey information, are these users not absorbing it?) In Wolfe’s edition of Porta, the discs might be easier to cut out and assemble into volvelles, but someone in the print shop labeled each disc in every copy, by hand, with its identifying number. There are aspects of hand-press book making that can be thought of as assembly line production: each person has a part to play in turning a stack of blank paper into a sequential printed text, and everyone needs to work efficiently to keep the process moving forward. But hand-press books are still hand-made, and some aspects of early modern printing require individual attention to individual copies in order to create the finished book.
One last piece of information: what is it that Porta’s volvelles are conveying, once assembled? In the words of Bill Sherman,
it’s a ‘polyalphabetic substitution cipher’ that allows you to replace plaintext alphabetical messages with a range of ciphertext alphabets (in this case made up of symbols instead of other letters) once you and your recipient agreed upon a starting place for the rotating inner disk. This represented a huge step in information security since monoalphabetic substitutions (where one letter is always replaced by the same arbitrary letters or symbol) are very easy to break. These systems were invented, it seems, by Leon Battista Alberti c.1467 and could take the form of a table or a disc. Porta is one of the scholars who used volvelle technology to tweak the system and put it in the hands of readers.
Bill is the curator of the Folger’s next exhibition, “Decoding the Renaissance,” running from November 11 through March 1. Porta’s work will be part of the exhibit, along with many other important and fascinating texts on codes. If you’ll be in DC, come and see it to learn more about ciphers and the Renaissance!