HEVELIUS, Johannes (1611-1687). Mercurius in sole visus Gedani, anno christiano MDCLXI... cui annexa est Venus in sole pariter visa, anno 1639... Liverpoliae, a Jeremia Horroxio, nunc primum edita. Danzig: Simon Reiniger for the author, 1662.

First edition of Hevelius' observations of the transit of Mercury on 3 May 1661 and of Jeremiah Horrocks's observations on the transit of Venus—the first transit of Venus observed by an astronomer. Illustrated with Hevelius’ own handsome engravings. Hevelius’ primary work is followed by the first published description of the important observations by the short-lived English astronomer Jeremiah Horrocks (1618-1641) of the transit of Venus of 24 November 1639, with supplementary notes by Hevelius. Horrocks was the first astronomer to observe a transit (or conjunction with the sun) of Venus, an event that he had predicted through close study and correction of Kepler's tables. His observations enabled him to make the first accurate calculations of the diameter of Venus and of the constants of its orbit. This was the first of any of Horrocks's manuscripts to be published.

This volume also includes Hevelius’s observations of the partial lunar eclipse of 30 October 1659, of the solar eclipses of 14 November 1659 and 30 March 1661, and of a new star (probably a nova) in the "neck" of the constellation Cetus, first observed in 1638 and which he calls Mira (“the wonderful”). In 1660 and 1661, Hevelius also observed a paraselene (mock moon), and a parhelion (mock sun). Norman 1067.

Folio (340 x 220mm.). Engraved allegorical title vignette by Frans Allen after Adolph Boy, 10 engraved plates by Hevelius, letterpress tables, woodcut and type-ornament head- and tail-pieces and initials, in-text engraved illustration (very pale corner dampstain to title and following few leaves, 2K gathering browned, occasional light spots/toning.) Modern vellum-backed marbled boards, spine lettered in pencil. Provenance: neat early indexing on title page – Marcel Destombes, 1905-1983, historian of cartography and scientific instruments (bookplate).