The First Phases of the Theoricæ Planetarum Printed Tradition (1474–1535): The Evolution of a Genre Observed through its Images

Abstract

In the Renaissance, two genres of illustrated printed books played a major role in the European diffusion of standard astronomical diagrams and figures: that of the treatises on the Sphere, and that of the theories of the planets. They shared important characteristics. Both were textbooks, used in the universities (albeit sometimes also addressing a wider public), and their processes of evolution were similar. This evolution was mainly prompted through a succession of commentaries attached to a common nucleus (the original text of Johannes de Sacrobosco, in the former case, of Georg von Peuerbach in the latter), and, secondarily, through the writing of new versions of the primary text incorporating new elements, or elements taken from the commentaries.The very first editions of Sacrobosco's De sphoera1 and of the predecessor of Peuerbach's treatise, the Theorica Gerardi,2 alias Theorica vetus, attributed to Gerardus Cremonensis, had no diagrams.3 Another important medieval treatise on the planets, Campanus de Novara's Theorica planetarum, is not discussed further here because it was never printed.4 In contrast, the editions of Peuerbach's Theoricoe novoe were, from the beginning, always illustrated, as were those of Sacrobosco from 1478 onwards. In that year, Franciscus Renner printed, in Venice, an edition of the Sphoera with three diagrams, and Ehrard Ratdolt followed suit in 1482. The 1485 Ratdolt edition had a larger set of diagrams, and the next edition, printed by Johannes Santritter in 1488, constituted the first complete Venetian illustrated Sacrobosco. From that date, the 'standard Sacrocosco' became a lavishly illustrated book, as the 'standard Peuerbach' had been from 1474.The importance of illustration was thus common to both genres, but, at closer examination, a significant difference appears. The iconography of the Sphoera evidently underwent changes during the (approximately) 150 years of the work's life as a printed textbook: in Oronce Fine's Sphoera mundi5 and in the monumental editions with commentaries by Francesco Giuntini6 and Christoph Clavius,7 for instance, it was richer and more sophisticated than in the modest octavo used by students from the beginning of the sixteenth century. However, it remained, as a rule, basically conservative, retaining throughout its successive editions the original set of diagrams (or recognizable reinterpretations of that set), which was associated with the fundamental elements of the cosmological doctrine transmitted by the text. By comparison, the illustrations in the Theoricoe tradition appear to have undergone a continuous process of transformation and reinvention. Although a core of diagrams remained from the beginning to the end,8 new diagrams were regularly introduced by editors and commentators, thus revealing how much the Theoricce served as an active laboratory of astronomical thought.The fact that the printers of Peuerbach's treatise seem to have been reasonably ready to pay, from time to time, for new sets of woodcuts sheds light on some practical aspects of the production of astronomical manuals. We know that illustration gave books more commercial value and attractiveness, but could add considerably to the cost of their printing and generate complication and delays. Editors and booksellers were thus obliged to calculate the most satisfactory balance between these factors. Failure could lead to bankruptcy, as in the case of Aldrovandi, who almost ruined himself (and his unfortunate associate, Francesco de Franceschi),9 in attempting to print an Historia naturalis. The intention was that the project (which in the event was never completed) would be illustrated by woodcuts copied, from Aldrovandi's own collection of watercolours,,0by Cristoforo Coriolano, a German engraver who remained in Aldrovandi's service for almost ten years.11Aldrovandi's experience shows how practical pitfalls could jeopardise the chances of commercial success. …