Back in July 2014 I posted about volvelles (LINK HERE)- manuscripts, and later printed books – which incorporated designs or texts over which moving dials or pointers were fixed, enabling the user to calculate or combine pieces of information in the text, for example for computing astronomical or astrological charts. Ramon Lull is usually credited with inventing this ‘ars combinatoria’.
My post went on to consider other kinds of combinatorial text, from Swift’s Lagado machine in Gulliver’s Travels, to Borges. I also linked to related posts about, among others, Calvino, OuLiPo, Permutational Poetry, and so on.
I’ve just come across a post from the iris website – the Art and Archives blog of the J. Paul Getty Museum in Los Angeles – by Rheagan Martin: ‘Decoding the Medieval Volvelle’, dated 23 July 2015. This post, like mine, gives historical context to the phenomenon of volvelles, and includes some lovely images, with links to the exhibition which ran that year, and to zoomable illustrations from books that were in it. I recommend you take a look at it – and, I hope, back at my original volvelles piece.