Books

Folio (388 x 250 mm). Work in five parts, each with separate half-title page, but continuous pagination and signatures. Text in Latin with small sections in Greek. [40], 337, [3] pp., folding letterpress table, woodcut initials, head- and tailpieces, approx. 300 woodcut diagrams in text, complete with first and final blanks. Signatures: [pi]2 (2*-4*)6 (A-2D)6 2E8 ([pi]1, 2E8 blanks). Recased in early 18th century vellum, new endpapers, brown-dyed edges. Text mostly heavily browned, tiny holes in leaves O6 and P1 with loss of a few letters of text, repaired tear in leaf T1 without loss, a few wormholes at gutter (sometimes touching text), burn hole in leaf S6. Provenance: "Pertinet ad Bibliothecam [--]", obscured inscription on title-page. Although heavily browned as usual, a very good and wide-margined copy. FIRST EDITION, AND EXCEPTIONALLY RARE, of Kepler's most important work and a masterpiece of modern astronomy containing the first enunciation of the first two laws of planetary motion: the law of elliptical orbits, formulating that the orbits of planets are shown to be elliptic rather than circular, demonstrated by his calculations of the orbit of Mars, and the law of equal areas, which shows that the planets move faster when they are closer to the sun. In 1607 Kepler had the wood blocks cut in Prague, and in 1608 he sent the text to be printed by the successors of Ernst Vögelin (1529-89) in Heidelberg. The absence of an imprint was due to the fact that the edition was not intended for commerce: the Emperor held the rights to its distribution, since Kepler had written it in his post of court astronomer, and it had been printed at imperial expense. Kepler, however, thought otherwise, his salary being long in arrears, and he sold his copies to the publisher. Although the size of the press run is not recorded, Kepler later stated that only "a few copies" had been printed (Caspar, p. 55). The influence this book had on other great astronomers, from his contemporary Galileo to the later Newton, was substantial and enabled Newton to form his own laws of motion and universal gravitation. Kepler's and Newton's laws became the basis of celestial mechanics. Kepler, a student of the "cautious Copernican" Michael Maestlin in Tübingen, used Copernicus's theory of heliocentrism as the basis for his treatise, and combined it with the observational accuracy of Tycho Brahe, whose calculations he acquired through his post as imperial mathematician to Rudolf II, following Tycho's death in Prague in 1601. Disagreement with Tycho's heirs led to delays with the publication which only commenced in the summer of 1608, once Tycho's son-in-law, Franz Tengnagel, was able to add a note to the reader regarding Kepler's deviance from Tycho's calculations. The publication was supposed to be distributed privately by the Emperor, who held the rights to its distribution, since Kepler had written it in his post of court astronomer, but Kepler sold some copies to the printer Ernst Vögelin successors in Heidelberg in an attempt to recoup some of his salary, which was in arrears. Although the size of the press run is not recorded, Kepler later stated that only "a few copies" had been printed (see Caspar, p. 55). Johannes Kepler stands, with Galileo between Copernicus and Newton among the founders of modern astronomy and of a new conception of the universe. 'The New Astronomy' is perhaps his most important book . . . Compelled as a Protestant to give up his post as a teacher of mathematics at Graz, he joined Tycho Brahe, the famous Danish astronomer, at Prague and on his death became mathematician to the Emperor Rudolf II, a great patron of science. It was fortunate that Kepler was able to use the mass of material collected by Tycho Brahe. Brahe had greatly improved the construction of astronomical instruments and with these had made systematic and accurate observations. . . Visit our website for further reading and additional images!