Romae: Ex Typographia Dominici Basæ, 1585. Octavo, 323, ; VG; bound in contemporary full vellum, ink titling to spine; mild shelfwear and rubbing; small red ink name stamp to ffep; small bookseller ticket to front pastedown; small scattered early marginalia; Title vignette (Jesuit device); Title vignette (Jesuit device); Errata on page 323; Pages 202, 203, 206, and 207 misnumbered 102, 103, 106, and 107 respectively, 206 and 207 hand-corrected; extremely scarce; SP consignment; shelved case 3.
Shelved Dupont Bookstore
The foremost early figure in Jesuit science, Christopher Clavius (1538-1612) was one of the chief architects and defenders of the 1582 calendar reform under Pope Gregory XIII, leading to the modern Gregorian Calendar. Pope Sixtus V said: "Had the Jesuit order produced nothing more than this Clavius, on this account alone the order should be praised". His Euclid Elementorum (Rome, 1589) was brought by Matteo Ricci to China and translated into Chinese. In his Astrolabium (Rome, 1593) he uses a dot to separate whole numbers from decimal fractions and is arguably the first to do so. His Gnomonices (Rome, 1602) contains every then known principle concerning the measurement of time. Galileo was a frequent visitor to the Jesuit Roman College, and he and Clavius corresponded frequently.;