HALLEY, Edmund (1656-1742). Astronomiae cometicae synopsis. Oxford: University Press at the Sheldonian Theatre with the imprimatur of Arthur Charlett, 8 June 1705.
2o (355 x 232 mm.) Collation: A2 B1. 3 leaves, unpaginated. Caption title, printer's large engraved device at end including engraved colophon, typographic tables on A1v and A2r, small woodcut diagram on A2v. No visible watermark. (Creases from earlier folding, very slight soiling along one or two folds, upper edges a trifle frayed, B1v with slight soiling to upper margin and discoloration along gutter margin, possibly from an earlier guard.) Unbound, untrimmed (sewing holes evident); folding cloth chemise and morocco-backed gilt folding case.
FIRST EDITION, OF THE UTMOST RARITY, of Halley's presentation of his theory according to which comets belong to the solar system and move in eccentric elliptical orbits. In this work, the scientific achievement for which he is best known, Halley set forth a method of computing the motion of comets and establishing their periodicity in elliptical orbits, and identified the comet that was to bear his name. Halley's interest had been aroused by the bright comet of 1680, but it was only after the publication of Newton's Principia in 1696 (of which Halley had borne the expenses and to which he had contributed valuable editorial aid) that he was able to undertake an intensive investigation of comets. Newton (Book III, proposition 40), had established that "cometary orbits move in conic sections... having the sun as a focus, according to the law of areas," and he theorized that their orbits would be "so near to parabolas, that parabolas may be used for them without sensible error" (DSB). Halley's tabulations led him to favor the likelihood of an elliptical orbit. After first tabulating all available cometary observations from the 14th through the 17th centuries, he used these to calculate and tabulate the orbits of the 24 comets seen between the years 1337 and 1698. The results of his calculations, which he "sought to make as accurate as possible, not without the labour of many years" (2nd English edition, in Gregory, Elements of astronomy, II, p. 897) showed that three of these recently observed comets, seen in 1531, 1607 and 1682, had a nearly identical orbit, describing an elongated ellipse. Halley concluded that they were one and the same body, and later identified this comet with those sighted in 1305, 1380 and 1456. "Halley next set about calculating its return and, allowing for perturbations by the planet Jupiter, announced that it should reappear in December 1758. The comet was in fact observed on 25 December 1758, arriving some days later than Halley's calculations had indicated, but in that part of the sky he had predicted... Although this work aroused the interest of astronomers, it was not until the 1682 comet reappeared as predicted in 1758 that the whole intellectual world of western Europe took notice... The object was named 'Halley's comet'. This succcessful prediction acted as a strong independent confirmation of Newtonian gravitation" (DSB).
Halley's Astronomiae cometicae synopsis was translated into English ("from the copy printed at Oxford") by John Senex and published later the same year, as A synopsis of the astronomy of comets; it was published again in a longer Latin version in the Philosophical translations for 1704-1705. This first edition must have been printed in a very small number of copies; in a letter of 23 June 1705 to the printer Arthur Charlett, Halley thanks him for his "kind endeavours" and asks for a few more copies of his "papers, for most of the ten you were pleased to send me, were soiled so as not to be fit to be presented to Quality" (Macpike, p. 125). It is ONE OF THE GREATEST RARITIES OF ASTRONOMICAL LITERATURE. The ESTC lists only four copies, at Harvard, the Bodleian (2), and Oxford, Worcester College.
MacPike, Correspondence and papers of Edmund Halley, p. 275; cf. Dibner 12 and PMM 173 (English edition); Norman 978.