Nürnberg: Stuchs, 1514.
First edition of Werner’s most important book, an extremely rare and highly influential work on cartography and navigation, containing the first published direct translation of any part of Ptolemy’s Geography from the original Greek. It includes the first publication of the Werner map projection, which was widely used for world and continental maps through the sixteenth and seventeenth centuries, notably by Mercator, Oronce Finé and Ortelius. The book also contains the invention of the lunar distance method of longitude determination, and of the cross-staff, an instrument designed to make the necessary astronomical observations at sea.
Born in Nürnberg, the mathematician, astronomer and geographer Johannes Werner (1468-1522) was a student at the University of Ingolstadt from 1484. He studied in Rome between 1493 and 1498 before returning to Nürnberg as chaplain of St. Johannes’s church. There he became part of a tight knit circle of mathematical practitioners in Nürnberg, Ingolstadt, Vienna and Tübingen who were largely responsible for establishing mathematics as a discipline in the central European universities.
Werner’s edition of the first and part of the seventh book of Ptolemy’s Geography, the Nova translatio Primi Geographiae, was the first translation from the Greek since the original translation made by Jacobus Anglicus around 1406. Werner stated clearly that his rationale for the undertaking lay in the many errors contained in Anglicus’s edition and in the succeeding ones, which were all based on Anglicus’s rendering of the Greek text. Werner had access to the papers of Regiomontanus, which were part of the scientific library of his former mentor Bernhard Walther and had been inherited by Werner’s friend and neighbour Albrecht Dürer who purchased the library, along with Walther’s house, in 1509. These papers may have included Regiomontanus’s notes for his own translation of the Geography which he had planned but failed to complete before his death in 1476.
Werner’s greatest personal input in this edition were his mathematical notes to the first book, where he criticized Ptolemy, often on the grounds that taking him literally would result in ‘deforming the earth’s shape’. Drawing inspiration from Ptolemy and from astronomical usage, Werner also made an original contribution to cartographical projections with his Libellus de quatuour terrarum orbis en plano figurationibus ab codem Ioanne Verneo novissime compertis et enarratis. Here Werner gave a theoretical discussion of two generalizations of Ptolemy’s second conic projection. His Propositio IV modifies Ptolemy’s methodology by requiring that lengths be preserved on all parallels, represented by concentric arcs, and on all radii. Werner further modified the projection in a way that makes the North Pole the centre of what in modern terms would be called a system of polar coordinates. In Propositio V he also requires that a quadrant of the equator have the same length as the radius between a pole and the equator. These modifications provided the first solution to the problem of representing the surface of a sphere within a finite area.
The ‘lunar distance’ method of determining longitude, first published in the present work, exploits the fact that the moon moves relative to the fixed stars owing to its rotation about the earth. By measuring the angular distance of the moon from certain stars it is possible to determine the local time, and hence the longitude. In proposing this method, it seems that Werner may have been inspired by a letter of Amerigo Vespucci written in 1502 where he wrote: “. . . I maintain that I learned [my longitude] . . . by the eclipses and conjunctions of the Moon with the planets”. To make the necessary measurements Werner designed and advocated the use of the cross-staff, an instrument which measured with precision angles in degrees of arc. It was descended from the Jacob's staff, a medieval instrument first referred to in 1342 in a treatise by Levi ben Gerson, and used principally by surveyors and for military purposes for distance measurement. A decade later, Apianus was advocating the use of Werner’s cross-staff to measure lunar distances in his Cosmographicus liber (Landshut, 1524), and by the mid-sixteenth century Portuguese navigators were using it in their southward exploration by sea of the Atlantic Ocean. It was eventually to displace both the seaman’s quadrant and astrolabe.
The work is dedicated to the Nürnberg merchant Sebald Schreyer (1446-1520) and the wealthy lawyer and humanist Willibald Pirckheimer (1470-1530), who was to publish his own translation of Ptolemy’s Geography in 1525.
VD 16, P5208. Not in Adams or BL STC German. No copies located in auction records in the last 40 years. OCLC locates only three copies in America (Folger, University of Illinois and John Carter Brown).
Folio (311 x 208 mm), ll , later flexible vellum, some marginal water staining to the first 10 leafs, otherwise fine and clean.