Gemma Phrisius Dockumensis.
Engraving, 190 x 135mm. 7½ x 5¼", set in text.
Portrait of Gemma Frisius (1508-55), a physician, mathematician, cartographer, philosopher, astronomer and instrument maker. Not only was he the first to propose using triangulation for mapmaking, but he also posited that an accurate clock could be used to determine longitude, two centuries before it was achieved. Published in Isaac Bullart's 'Académie des Sciences et des Arts 1682'.
[Ref: 25775] £220.00