Gerhard Mercator’s world map of 1569

Gerhard Mercator’s world map of 1569 is the first to make use of a cylindrical projection in which the spacing between parallels of latitude increases as they approach the poles. As a result, the proportions of coastlines at higher latitudes are preserved, even as they are depicted as far larger than they would have appeared on a globe (see next two slides). The Mercator projection became the standard map projection for nautical purposes owing to its ability to represent lines of constant course, known as rhumb lines, as straight segments which conserve the angles with the meridians.

Commentary. Philipp Nothaft (May-June 2019)