This note accompanies the follow episode(s):
The Writer’s Almanac for March 5, 2017: Anxiety

Mar. 5, 2017: birthday: Gerardus Mercator

It’s the birthday of Gerardus Mercator, born in Rupelmonde, Flanders (now Belgium), in 1512. He developed the world-mapping technique that we still use today and call the “Mercator projection.” He developed a method to accurately project the globe onto a flat surface so that longitude and latitude lines would always be at right angles to each other.

When he first published his world map in 1569, it revolutionized navigation. For the first time, sailors could plot a route between any two destinations in the world using a straight line, and then follow that route without having to adjust their compasses.

To project the globe onto a flat surface, Mercator straightened the vertical lines of longitude into parallel lines, and he added space between the horizontal lines of latitude. This distorted the distance at the North and South Poles, which is why Greenland and Antarctica appear so large on flat world maps. The Mercator projection soon became the authoritative world map. Mercator was also the first person to use the word “atlas” to refer to a book of maps.