Volvelles, what a passion!
PrPh Books has always paid special attention to scientific books, selected not only for their rarity or provenance, but also for their physical characteristics or material make-up: among them, interactive books with movable parts are especially fascinating and we are very pleased to offer a selection of these scientific ‘pop-up’ books, in manuscript and printed form as well. These volumes contain – as an integral part of the textual content of the work – different types of working volvelle diagrams, including mounted quadrants, lunar and sun dials, and other paper instruments.
These sophisticated and delicate paper mechanisms offered a cheaper alternative to metal devices, and were readily used by readers, who were able to physically move the volvelles, generally by rotating circular discs. The individual components of volvelle diagrams were designed by the authors themselves and printed on single sides of a separate leaf of thick paper, occasionally with extra reinforcements in order to withstand the intensive use by readers. These individual parts had to be cut out and attached with knotted thread onto the centre of the appropriate diagrams or bases; strings with seed pearls, paper pointers, or articulated brass arms or brachiola could also be added. Especially in the case of complex volvelles containing sub-parts, their construction was not an odd undertaking for binders or owners, and volvelle diagrams were generally assembled directly in printing houses, before being sold and often under the supervision of the author himself.
The earliest recorded printed volvelles appeared in the Calendarium published in Nuremberg in 1474 by the famous mathematician Johann Müller, better known as Regiomontanus. The physical construction of the diagrams included in his work follows the instructions provided by the fourteenth-century Catalan philosopher Ramón Llull in his Ars generalis and Ars brevis, both of which Regiomontanus owned in manuscript.
In 1475, Pope Sixtus IV summoned Regiomontanus to Rome to consult on the calendar reform, and he prematurely died in the papal city in 1476. That same year, Erhard Ratdold simultaneously issued the Latin and Italian versions of the Calendarium for the years 1475-1530. Both editions were extraordinarily popular, contributing significantly to Regiomontanus’s posthumous fame. According to Zinner, a total of 1,000 copies may have been printed. However, only a few illuminated copies are known: the red-and-black printed title page of the copy presented here is lavishly illuminated on gold ground, a feature which suggests – together with the still unidentified coat of arms included in the border – a very distinguished patron. The instruments are coloured in deep yellow, simulating the brass used in metal devices (for the complete description click here).
Regiomontanus’s Calendarium also circulated in manuscript form among his friends and fellow astronomers. We offer an extraordinary example of this circulation in the form of the earliest known Italian manuscript of the work, possibly dating to about 1474. It is included in a miscellaneous codex produced in Turin, and ‘used’ – as his ownership inscription attests – by the Augustinian monk Antonius de Lanceo at the monastery of San Cristoforo (for the complete description click here). Only two manuscript copies of the Calendarium are known to have come on the market in living memory: the manuscript presented here, and a manuscript once preserved in the Lambach Abbey (Austria), which was later bought by Laurence Schoenberg and has been held at Princeton University since 2011.
After his death in 1476, Regiomontanus’s surviving manuscripts were sought out. The honour of editing at least two of his unpublished works – even if without dials – was given to Johannes Schöner, a mathematician, astronomer, cartographer, and scientific instrument maker from Karlstadt, in Bayern. Schöner was also active as a printer and even set up a press in his house; he is also responsible for drawing and constructing the volvelle diagrams for his own books, as in the fine Aequatorium Astronomicum, which first appeared in Bamberg in 1521. This work was later included in his Opera mathematica, issued posthumously by his son Andreas in 1551, an impressive volume offered here in the stunning Honeyman copy, containing eleven volvelle diagrams and bearing a strictly contemporary blind-stamped binding executed in Wittenberg by Jacob Fritzsch (for the complete description click here).
Volvelles are also found in the rare first edition of the cryptographic work De furtivis literarum notis by Giovan Battista Della Porta, printed in Nepal in 1563 (for the description click here). The work contains three full-page, movable diagrams, each consisting of a base bearing dials of letters and numerals and a circular volvelle with a dial of cryptic signs and a pointer-finger issuing from clouds. These volvelle diagrams could be used both for the encryption of secret or occult messages and to decipher the codes presented by Della Porta himself.
Each of the copies described here contains assembled (and still working) instruments. These interactive books were meant to be used by their readers, and copies with uncut volvelle printed on separate leaves have thus generally not survived. We are, therefore, especially proud to be offering a book containing a volvelle sheet in its original uncut state: none other than a copy of the De compendiosa architectura, & complementi artis Lullij by Italian philosopher Giordano Bruno, published in Paris 1582 (for the complete description click here). The Compendiosa architectura is bound in a volume that opens with the two works by the aforementioned Ramón Llull, and, quite exceptionally, included between fols. B7 and B8 is an additional folding sheet, printed only on one side, containing two circular volvelles to be cut and mounted onto the alphabetical dial on the verso of fol. B8. What’s more, this leaf is in an uncut state and includes instructions to the printer or binder: “Hi duo circulli includentur in eo circulo qui habetur folio 16.”; evidently these instructions were not heeded, as the printer or binder failed to cut and mount the pieces on the appropriate diagram. Perhaps a sign of ignorance, or lack of attention, this simple oversight proved to be a lucky mistake, giving us precious insight into the world of Renaissance printing.