Theorica planetarum, Tractatus de sphaera, and other texts

*NEW Aug. 2019:* The World of the Sphere: Diagrams from De Sphaera Mundi

This extensively glossed astronomical miscellany, the only item in this exhibit not from the Lawrence J. Schoenberg Collection, was acquired by the Kislak Center in 2017. It contains a selection of Latin astronomical texts, including the widely disseminated Theorica planetarum (the basis for Peuerbach’s Theoricae novae planetarum), Sacrobosco’s Tractatus de sphaera, and a copy of the Alfonsine Tables. The Tables have calculations added in the bottom margins for specific cities, mostly in Germany, and the Tractatus de sphaera concludes with a colophon dated 30 December 1481 (fol. 36v). On the final leaf are a Hebrew alphabet in a cautious hand and a reference to Magdeburg (fol. 95v).

Many of this manuscript’s diagrams are painstakingly annotated, reflecting an accretion of knowledge that continued after the first copyist; for instance, a climate zone diagram includes a number of place names written into the appropriate zones (fol. 33v). This codex also contains six volvelles, including larger ones depicting planetary movements as well as small, marginal volvelles illustrating geometric principles. Yet this manuscript’s late date of production, after the birth of Copernicus and the first printed edition of Sacrobosco's text, points to the transience of its educational value.