Year of Invention: 1569
What Is It? An accurate projection of the three-dimensional globe onto a flat
Who Invented It? Gerard Mercator (in Duisburg, Germany)
Street maps, world maps, resource maps, population maps: We rely on maps to tell us where we are and to show us where we want to go. Maps show us the spatial relationship of places and geographic features.
Long voyage navigation was dangerous and uncertain until maps accurately showed voyagers how to get where they were going. Accurate maps—for the first time—created an understanding of the world around us. With Mercator’s maps, ancient Greek geography ended and modern geography began.
Historically, maps were hand-drawn sketches, often drawn from memory or from interviews with those who were there. Such maps included gross errors of distance and proportion. Mapmakers typically made no effort to keep their maps in any scale. A distance of 50 miles might be represented as one inch on one side of a map and as five inches on the other side, with no indication of any scale change. Most travelers relied first on landmarks, second on the sun and Pole Star (North Star), and used maps only as backup.
Arab mapmakers (cartographers) maintained more accuracy and science in their maps during the third through twelfth centuries (the European Dark Ages) than did Europeans. By the early 1300s European cartographers were copying from Arab maps. By the mid-1300s, generally accurate maps (called “portolans”) based on compass readings and shore landmarks directed merchants from port to port within the Mediterranean. Outside the Mediterranean, however, maps were horribly inaccurate. When Magellan reached the Philippines in 1521, he miscalculated his position by over 3,000 miles.