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If someone told you that the earth was flat or that it was round, would it make any difference to you? The dimensions of the planet are so vast compared to the size of any animal, that the earth’s surface can indeed be considered flat. And in actual fact, the maps that depict it are almost always two-dimensional.

Nico Zardo


Cartography (from the Greek words khartes, “map”, and graphein, “to write”) is a system of symbols representing a geographical location, the status or the development of a phenomenon or of an event.
Its contribution to exploring the planet has accompanied the progress of our civilization and has often determined great changes. Consider the brave conquests of Columbus: they could not have taken place if the information collected by cartographers like Paolo Toscanelli had not given him the idea (erroneous but lucky!) that he could reach the Indies by travelling westward, confiding in a round and certainly smaller world than he thought.

 

THE FIRST KNOWN MAP, dating back to 7000 B.C., is a mural whose interpretation is still today controversial and that could represent the ancient city of Çatalhöyük, in Anatolia.
In the 6th century B.C., Greek philosopher Anaximander, having observed that the sun, the moon and the stars rotate around the earth, proposed the idea that the latter was a kind of disk suspended in space. Plato (427-347 B.C.) and Aristotle (384-322 B.C.), speculating on their observations of the stars, affirmed that the Earth is a globe and, in 250 B.C., Eratosthenes of Cyrene actually succeeded in calculating its radius, with an approximation of 5% compared to current knowledge.
The ancient Romans did not delve in-depth into the studies on cosmography performed by the Greeks, and – considering the practical aspect of their military management of the territory – drew synthetic maps that in the 4th century described the layout of the roads of the Empire. And so 200,000 km of roads are collected in the Tabula Peutingeriana, stored in the Austrian National Library in Vienna. In his Geography, Ptolemy – to whom we owe the idea of the geocentric system – in the 2nd century further developed the work by Marinus of Tyre who had introduced the concepts of latitude and longitude, and depicted the world known then in 26 maps.

 

DURING THE MIDDLE AGES the prevalently religious conception of reality has the upper hand over scientific observation. The Arabs recovered and developed the experiences of the Greeks, Romans and Indians. Arab geographer Muhammad al-Idrisi, who lived in Sicily at the court of Roger II, in 1154 created the Tabula Rogeriana. In it, he collected the knowledge of the classical geographers and information by Arab explorers and merchants, depicting a map of the world that contained all that was known at the time of Africa, the Indian Ocean and the Far East, and was considered the most accurate world map for the next three centuries.Creating a geographical map was a very complex feat because it required knowledge and information that were not readily obtainable. Alexander the Great’s travels up to the Amou Darya and Indus Rivers, those of Marco Polo from Venice to China, or the African explorations of the 18th and 19th centuries by Burton and Speke, Livingston and Stanley, of which written reports existed, could not translate into a map because traveling on foot allowed acquiring knowledge of only a very limited area. Navigators could find information on the pilot books that described the coasts and the routes with words and drawings and through the compass, an invention of Chinese origin introduced in Europe in the 12th century.

 

PROOF THAT THE EARTH WAS ROUND came when Ferdinand Magellan and Juan Sebastián Elcano (1519-1521) circumnavigated it. From a cartographic point of view, the problem of its representation on paper was given by the deformations deriving from projecting its spherical surface onto a flat plane. (See box on page 166).
In 1569, the Flemmish Gerardus Mercator used a cylindrical projection to create a large map (202x124 cm) that for the first time allowed viewing the entire known world at one glance - a world map that, with subsequent modifications and updates, is still used today. The defect in Mercator’ projection – created to guide merchants along the sea routes to the New World – was that as we move away from the Equator, the surfaces become altered to the point where the data obtainable beyond the 70th parallel north or south are not reliable.

 

THE CARTOGRAPHIC REPRESENTATION OF THE WORLD HAS A VERY STRONG SYMBOLIC IMPORTANCE, capable of influencing the idea that every person born or living in a given territory has of other places on the Earth. The size of a nation or its position - north or south - has always carried great importance. To try and rebalance the idea of the world based on Mercator’s image, in 1973 a modern cartographer, the German Arno Peters, redesigned the world map, respecting all geographical parameters that could give rise to a comparison of surface or position. What we could call a democratic depiction of the Earth: the comparison between the two representations can be seen on page 168!
Recourse to globes opens a tentative route to a 3D representation of cartography. Two are the most famous and spectacular: they are almost 5 meters in diameter, were built in 1683 (after two years of work!) by Venetian friar Vincenzo Coronelli, on behalf of Cardinal César d’Estrées, to pay homage to Louis XIV, and can still be seen in the François Mitterrand Library in Paris.
The third dimension in cartography appeared at the end of the 18th century when the first triangulation work allowed identifying altitudes, the depiction of reliefs with the representation of contour lines - the lines that unite points located at the same sea level height (isoipse: above sea level; isobar: below sea level) and that allow assessing slopes in the terrain.
With recent aerial and satellite filming, remote sensing techniques and their codification into digital data, the fourth dimension – time - was introduced. Through visual monitoring, surveys on the territory can be performed, highlighting changes due to geological phenomena or to human interventions.

 

CARTOGRAPHY HAS FOR SOME TIME BEEN USED NOT ONLY FOR GEOGRAPHICAL REPESENTATIONS: the graphic combination of social, technical and scientific data constitutes a form of communication that allows knowing and assessing a large number of information scenarios and disseminating them effectively and synthetically.
French engineer Joseph Minard (1781–1870) is considered one of the founders of infographics. In 1869 he depicted Napoleon’s military defeat in Russia in 1812 through diagrams reporting the occupation of the territory, the temperature, the itinerary and the advancing and retreating direction of the troops.
In 1854, the physician John Snow, after mapping in detail the roads and pipe systems in the various London neighborhoods, succeeded in identifying the center of the cholera contamination that originated in the well located in Golden Square. In 1933, Henry Charles Beck drew a map of London’s subway system, disregarding actual positions and distances but rendering the information reported immediate and effective.
American artist Mark Lombardi(1951-2001) is famous for creating graphic works illustrating the connections between the global élite spheres and the economic and financial fields with terrorism by basing his research on public information and investigating illegal practices in the globalized world.

 

TODAY, THANKS TO GPS AND TO DIGITAL MAPPING
mediated by Google who asks us where we are every time we turn to it, our relationship with geography, no matter where we are in the world, has no secrets. And not only: by elaborating our profiles and position in real time, we are spurred by the net to try the nearby fish restaurant (because two years earlier we added it to our preferences), to go to the cinema just around the corner that is showing a film by a director we expressed a liking for on some website, or to meet a Facebook friend who (we don’t know it, but Google does!) lives just a few hundred meters from where we are right now. You cannot escape: anywhere you may be, you are here!

 

THERE IS NO ONE MAP FOR ALL OCCASIONS!
Since it is impossible to project the earth’s spherical surface on a plane without deforming it, maps are approximate and are generally created based on the use that will be made of them. For aerial or maritime navigation, “isogonal maps” (or “conform mapping”) are used that preserve the magnitudes of local angles (fig. 1). In isogonal mapping, the meridians are straight and equidistant while the parallels are straight but not equidistant. Where the relationship between the surfaces useful in indicating borders or different areas is important, “equivalent maps” are used (fig. 2).
Here, the distance between parallels decreases as we go in the direction of the Poles. For road maps (fig. 3), where the relation between distances is fundamental, equidistant maps are used.
No map is capable of respecting all three of these elements; at most it can respect two of them.

 

 

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