Large 4to. (14), 115 ff., including allegorical engraved title and numerous woodcut diagrams and figures in text, many nearly full-page, and as usual lacking final blank. Bound in contemporary flexible vellum over pasteboards, raised bands on spine with title stenciled in ink, covers bowed and abraded, showing through to board at corners, patches of spine gone. Inconsequential soiling to upper blank margin of title; some leaves toned; thin line at upper margin bled from colored fore-edges. Generally a broad-margined fresh copy, very good.
First edition of New Theories of the Celestial Orbs Agreeing with the Observations of Copernicus, Magini's principal astronomical treatise. The work is of interest for the 16th century reception of Copernicus, whom Magini admired; and although he endorsed the unprecedented accuracy of Copernicus’ calculation of celestial movements he nevertheless publically retained his belief in geocentrism. His private correspondence, however, leaves no doubt that Magini became a “closet” Copernican (see below). Even so, Magini represents a progressive case of 16th century “establishment” science, and whether explicitly or not, and whether fairly or not, he is the target in much of Galileo’s revolutionary embrace of the Copernican system.
In this work Magini “took the position that Copernicus had so reformed astronomy that no correction of equal motions, or a very slight one, was now required... For although Copernicus had devised hypotheses which wandered far from verisimilitude, yet they corresponded closely to the phenomena.... He, therefore, collated the ideas of Ptolemy and Copernicus, adding new hypotheses of his own where they seemed necessary, and has written an introductory text or theory of the planets along these lines. He asserts that there was a great demand for such a theory of the planets which would abandon the outmoded Alfonsine hypotheses and conform his recent observations without such absurd hypotheses as Copernicus had imagined” (Thorndike VI.56).
In 1614, Magini would publish an ephemerides which was the first to take into account Kepler’s calculations in the Astronomia Nova (1609). That work, the Supplementum Ephemeridum contains an exchange of four letters between Magini and Kepler. Voelkel and Gingerich note that in Magini’s letter of 26 May (p. 267), there is a significant discrepancy between the extant manuscript and what Magini actually published in the Supplementum.
In thanking Kepler for sending him a copy of his Dissertatio cum Sidereo Nuncio, Magini closed the letter by saying “we are both Copernicans” —an admission he excised from the published text—and implying that the views he held privately may have differed from what he was willing to divulge in print. By 1614, there can be little doubt that Magini considered himself a Copernican.
Magini (1555-1617) held one of the two chairs of mathematics at Bologna at the time of the present work, to which he was elected over the young Galileo. This undeserved preference naturally aggravated the already advanced rivalry between the two. Magini was a talented calculator, producing the best ephemerides of his day, and was an accomplished geographer and cartographer.
* Adams M-119; Riccardi I.2.65.5; Luigi Campedelli in DSB IX.12-13; Gingerich, "Science in the Age of Copernicus," Harvard Library Bulletin XXVI, no. 4 (1978), no. 42; Thorndike VI.56-9.