Ptolemy's maps of Earth and the heavens: a new interpretation
type: Item
instance of: scholarly article
title: Ptolemy's maps of Earth and the heavens: a new interpretation
zbMATH Open document ID: 0778.01001
DOI: 10.1007/BF00375348
published in: Archive for History of Exact Sciences
publication date: 1993-04-01T00:00:00Z
review text: The author has carefully analyzed Ptolemy's two treatises, The Geography and The Planispherium, concerning the mapping of the points on a sphere into the plane. The commonly accepted interpretation was that Ptolemy utilized the mathematical tradition of the stereographic projection in both works although his geometrical procedures were not very elegant and consistent. After comparing the four maps, three in The Geography and one in The Planisperium, the author offers a new interpretation: Ptolemy's concern was not so much in mathematical consistency as in visual verisimilitude. Just as Ptolemy in The Geography simply offered the procedures for drawing maps in three different ways which are not stereographic, so in The Planispherium he just intended to draw the celestial circles in the plane without being involved in pointwise stereographic projection. Thus the instrument described in this treatise was different from the later astrolabe. This is a very interesting and stimulating paper on the history of stereographic projection as well as that of the earliest stage of `astrolabe'.
reviewed by: M.Yano
Mathematics Subject Classification ID: 01A20
zbMATH DE Number: 148362
zbMATH Keywords: Planispherium
zbMATH Keywords: stereographic
zbMATH Keywords: projection
zbMATH Keywords: astrolabe
zbMATH Keywords: geography
author: J. L. Berggren
MaRDI profile type: Publication
cites work: The Central Projection in One of Ptolemy's Map Constructions
cites work: Q5815583
cites work: Ptolemy's Geography, Book VII, Chapters 6 and 7
cites work: A History of Ancient Mathematical Astronomy
cites work: Q4110955
description: scientific article; zbMATH DE number 148362