
Petrus Apianus (1492–1552) and Gemma Frisius (1508–1555).
Cosmographia, Petri Apiani… additis euisdem argumenti libellis ipsius Gemmaa Frisii…Antwerp: Arnoldi Birckmanni, 1564.
Rare Book and Special Collections Division, Library of Congress (45)
Positions of the Sun, Moon, and Planets
Cosmographia by German mathematician Petrus Apianus provides a layman’s introduction to subjects such as astronomy, geography, cartography, surveying, navigation, and mathematical instruments. In this popular edition with changes by another noted mathematician, Gemma Frisius, movable paper instruments (volvelles) enabled readers to solve calendar problems and find the positions of the sun, moon, and the planets. Apianus depicted the cosmos according to the Ptolemaic system, which maintained that the sun revolved around the earth, a theory challenged by Nicolas Copernicus (1473–1543) in Apianus’s lifetime.