The Flemish cartographer Gerhardus Mercator (1512-1594) was among the first makers of modern atlases and is best known for his great world map, or chart, using the projection that has acquired his name.

In the history of cartography the work of Gerhardus Mercator illustrated a significant departure (though by no means a complete break) with the geographical traditions of the Middle Ages and those established by the revived Ptolemaic geography. It also signaled the late Renaissance convergence of academic cartography with the practical needs of navigators, an important step in the creation of that dynamic unity between science and technology that is one of the signal characteristics of the modern world.

Mercator was born Gerhard Kremer in Rupelmonde, Flanders, on March 5, 1512. He studied with the cosmographer Gemma Phyrisius at the University of Louvain and gained practical experience as an instrument maker and surveyor. His early successes brought him...