The Cartographer’s Dilemma: Matching Form to Function
In our History of Information Organization infographic, we highlighted cartography as one of the earliest forms of conceptual communication. The first maps appeared during the Stone Age and appear to predate written language by several millennia. Maps developed as intuitive and functional representations of our physical surroundings—water this way, shelter that way. In order to highlight important geographic features, maps must filter out less critical details. And when an inch equals a mile, the omissions outnumber the inclusions. The cartographer’s dilemma should be familiar to any project manager responsible for editorial decisions on content, especially for infographics and other data visualizations.
Different maps serve different purposes and thus display different details. Topographic maps are great for identifying river drainages. Highway maps help you find bridges to cross those rivers. And while the “x” on a treasure map indicates your desired destination, the “x” on a meteorological map may be a lightning downstrike. If you’ve ever had to choose between a pie chart, line chart, or bar chart, you know the challenge.
Distortions in world maps have always reflected the difficulty of presenting a round globe on a flat page. Some of the earliest world maps appear to depict the earth as a flat, disc-shaped body, but the circular shape was merely an attempt to show Eurasia and Africa surrounded by water. Despite the popular wisdom on this topic, very few educated individuals after Aristotle believed in a flat earth. Although many questioned Christopher Columbus’s navigational ability, nobody really expected him to plummet off the planet.
The representational distortion problem was solved (up to a point) by Flemish cartographer Gerardus Mercator in 1569. Mercator published a map of the world using a technique in which parallels and meridians were rendered as straight lines spaced so as to produce, at any point, an accurate ratio of latitude to longitude. The Mercator projection map solved many nautical navigation problems, although it has failed to disabuse schoolchildren of the notion that Greenland is twice the size of the lower 48 states.
Most map-making incongruities are more conceptual than geographic. One particularly famous distortion of perspective is illustrated in Saul Steinberg’s 1976 “View of the World from 9th Avenue” cover of The New Yorker. The work (below) trenchantly depicts a typical Manhattanite’s parochial view of the rest of the United States. The streets, sidewalks and buildings along 9th Avenue are prominent in the foreground. Behind that wall of modernity is the Hudson River, with a narrow strip of brown representing “Jersey” on the far bank. At an even smaller scale is the rest of the United States. Los Angeles, Chicago and a few other cities and states—the map makes no distinction—are distant places surrounded by the occasional outcropping (the Rocky Mountains). The Pacific Ocean, not much wider than the Hudson, separates us from nebulous chunks of land representing Russia, Japan and China.
Steinberg’s cover is a clear parody of a snotty New Yorker’s conception of flyover America and the uncivilized beyond. But it perhaps unintentionally also highlighted the distortions inherent in using lines and names to demarcate polities. Maps of Canada don’t note that Quebec is a separate linguistic sphere, and that many Québécois would prefer not to be a part of Canada at all. Maps of Iraq make no reference to Kurdish autonomy. Tibet and Xinjiang are both included in the borders of China, despite the regions’ respective hostilities toward Beijing.
Anyone trying to create visualizations from data sets faces the challenge of matching form to function and emphasizing clarity over comprehensiveness. Note that in many ways, Mercator’s map is just as skewed as Steinberg’s. His projection exaggerates the size of areas far from the equator to such an extent that Finland seems to rival India. One might argue the “civilized” north was thus privileged—even if inadvertently—over the colonized south and east. Taken together, these two famous examples demonstrate the extent to which a given map’s accuracy or distortion may be purely a matter of purpose and perspective.
Have any other example of notable cartographic errors and distortions based on the creator’s intent? Please share them in the comment section.