BAYER, Johann (1572-1625). Uranometria, omnium asterismorum continens schemata, nova methodo delineata, aeris laminis expressa. Augsburg: Christoph Mang, 1603.
2o (344 x 243 mm). Engraved title, 3 leaves preliminary text, 51 double-page engraved star maps by Alexander Mair, on guards throughout, letterpress descriptive text printed on rectos/versos of the maps, printer's woodcut device on colophon page, woodcut headpieces, initials and tailpiece. (Engraved title darkened and backed in heavy paper repairing long tear, dedication leaf with repaired tear affecting headpiece and a few letters on verso and with upper and lower margins strengthened, worming at gutters slightly affecting maps 20 and 24, small light crease to map 42, faint dampstain to upper fore-corners). 18th-century vellum over pasteboard, title lettered on spine.
Provenance: Augsburg, Benedictines of Sts. Ulrich and Afra (contemporary inscription on title, 18th-century engraved bookplate); Augsburg Stadtsbibliothek (19th-century inkstamp on title, later withdrawal stamp on verso).
FIRST EDITION OF THE FIRST ACCURATE STAR ATLAS. Earlier star catalogues followed Ptolemy's Almagest in using verbal descriptions to describe the location of stars within the 48 northern constellations of classical astronomy, an awkward system that occasioned constant errors and misapprehensions. Bayer, a lawyer and amateur astronomer, was the first to identify the location of stars within a constellation by the use of Greek letters (with the addition of the Latin alphabet for constellations with more than 24 stars). This simple innovation greatly facilitated the identification of stars with the naked eye, just five or six years before the invention of the telescope, and Bayer's stellar nomenclature is still in use today. Bayer used Brahe's recent observations for the northern sky, and included, in chart 49, twelve new southern constellations observed by the Dutch navigator Pieter Dirckzoon Keyzer and reported by Pedro de Medina. To simplify identification of the stars Bayer included in his typographic descriptions both the traditional star numerations within each constellation and the many names for the constellations employed since Ptolemy. The graceful figures of Mair's charts were based on those of Jacobo de Gheyn in Grotius' edition of the Syntagma arateorum (1600). Deborah Warner, The sky explored: celestial cartography 1500-1800 pp. 18-19; Zinner 3951; Norman 142.
BAYER. Explicatio characterum aeneis Uranometrias imaginum, tabulis insculptorum, addita, & commodiore hac forma tertium redintegreta. Augsburg: Johann Praetorius for Johann Gerlin, 1654. 4o (192 x 146 mm). Publisher's engraved device on title. (Final blank removed, foxing and bronwing.) Contemporary vellum over thin pasteboard. Second separate edition of the descriptive text without the engravings (first published in 1624). Norman 143. (2)