The Arrow Points North: Directional Orientation in Antiquarian Cartography

A regular reader of this blog (thank you) suggested I write on the topic of directional orientation in maps. Why are most maps oriented to the north? How did this practice originate? Is it necessary? Is it universal? The concept of a consistent northward orientation in all maps is neither as standardized nor as universal as it might seem at first glance. Even in modern times, it is more practical for many maps to have orientations other than north. The standard map of New York City for example, a variant of which is the classic New York Subway map, is commonly oriented to the northeast. In some non-western cultures with highly developed cartographic traditions, such as Japan, directional orientation is often not even a factor – but we will return to this at a later point.

In the west, if it can be called that, the tradition of orienting maps to the north began, as did so many things cartographic, with the 5th century Alexandrian geographer Claudius Ptolemy. Ptolemy’s work, the Geographica, is considered the first known geography. While the Geographica as it has come down to us today has no maps in it, it does contain detailed instructions for the construction of a map. These include a well laid out coordinate system and considerable geographic description.

Ptolemy's World Map

Ptolemy's World Map

The world as it was known to Ptolemy would have been centered on a relatively narrow latitudinal swath of land focused around the Mediterranean. The known lands at that time would have extended from the Strait of Gibraltar eastward as far as India. The southern lands beyond the Sahara and most of northern Europe and Asia were, for all intent and purposes, unknown. Thus, in order for Ptolemy to fit his map on a long narrow scroll, it would have been oriented to either the north or the south. Some scholars argue that this alone was sufficient motivation for Ptolemy to orient his map to the north. However, upon a closer examination of Ptolemy’s work, we can see that the real reasons behind his choices are more complex.

Ptolemy was very much aware that the world was spherical and that his home in Alexandria was in the Northern Hemisphere. With this knowledge in hand Ptolemy went about assembling his coordinate system. Ptolemy realized that for his coordinate system to be consistent, he needed a mathematical formula that would enable him to map the globular world on a flat surface – a projection. While Ptolemy did not invent the idea of a projection system, he did refine it considerably. Ptolemy’s intention was that his projection “above all the semblance of the spherical surface be retained” and that “it would be well to keep lines representing the meridians straight”. What he came up with is today referred to as a conical projection, with all longitudinal lines meeting at the north pole and radiating outward towards the equator, at which point they again radiate inwards, this time towards the South Pole.

While Ptolemy could have, in theory, calculated his meridians to meet at any point on the globe, the north pole was the most practical choice. The reason behind this is as follows. First, the Ptolemaic world was a band focused on the central part of the northern hemisphere. It did not extend exceptionally far either north or south. Since the meridians on his projection converged as the map went further north, the room for detail decreased – which was fine, since he didn’t know what was there anyway – leaving the plenty of room for detail in the known central parts of the maps. Second, the Ptolemaic world was divided into various climatic zones, the inhospitable frigid zones (near the poles), the hospitable temperate zones (the northern of which occupied much of the known world), and the inhospitable torrid zone on either side of the equator. With such a zonal layout intact, Ptolemy knew his focus must be on the habitable zones of the northern hemisphere and consequently he designed his projection to reflect this. Third, as an astronomer, Ptolemy would have made regular celestial observations and therefore been familiar with the movements of the heavens around the fixed point of Polaris, the North Star. Therefore, as a matter of making his projection mathematically simpler, of encapsulating his known world, and of aligning the globe with the celestial spheres, the choice of a northward orientation would have been obvious.

Beatus World Map c. 1050

Beatus World Map c. 1050

With the fall of the Roman Empire and the collapse of European civilization in to the middle ages, Ptolemy was, for all intent in purposes, forgotten. This world map, known as the Beatus Map, dates to c. 1050 and is one of the oldest surviving medieval maps. It is also a beautiful example of the mapping conventions that developed during this period. This maps offers a religious view of the cosmos and, though interesting on many levels, has little of the cartographic sophistication of Ptolemy’s Geographica. The map depicts the world as a flat disk centered on Jerusalem. Most medieval scholars believed that the Garden of Eden lie at the extreme eastern end of the world. Being closely associated with heaven, Eden the Earthly Paradise was naturally placed at the top of the map. Most other maps of the period followed suit. It was not until the Renaissance that the works of Ptolemy were rediscovered. With their coordinate system and scientific approach, Ptolemy’s maps were quickly recognized by Renaissance scholars as superior to most contemporary material. With the development of printing, Ptolemy’s maps were mass produced and, relatively speaking, widely available. These maps re-established the convention of a northward orientation.

World on Mercator's Projection

World on Mercator's Projection

It is also around this time that the Great Age of Exploration truly gets underway and maps suddenly were given a new purpose – navigation. Early sailors tended to either hug the coast or, when entering the open sea, travel in a straight line along a directional path. Consequently, what navigators need was a map that presented the entire world on a flat plane such that any two points could be connected with a straight line. In this way, a ship need only be oriented in the correction direction, and after a period of sailing, should, in theory, arrive at the desired destination. Enter the Mercator Projection. Mercator’s projection was essentially a navigational tool that sacrificed proportion for the ability to accurately connect all points with straight lines. These lines, which appear on most navigational maps, are called rhumb lines. The use of Mercator Projections, rhumb lines, and the compass for navigation solidified the convention established by Ptolemy.

1632 Tirinus Map of the Holy Land

1632 Tirinus Map of the Holy Land

Even so, not all maps were oriented to the north. Mapmakers regularly, though not frequently, oriented maps in other directions. Sometimes the decision to use an alternate orientation was based upon the need to fit a region of a certain form onto and appropriately sized sheet. Maps of the Holy Land, for example, were frequently oriented to the East. Several important maps of North America, including Blaeu’s Nova Belgica et Anglia Nova, also use unusual orientations. It is not until the 19th century that almost all new maps being made were given a northward orientation.

1843 Edo Map of the Vicinity of Mt. Fuji

1843 Edo Map of the Vicinity of Mt. Fuji

All the above applies to European cartography. Mapmaking in other parts of the world, like Japan for example, did not use an established directional orientation. Many Japanese maps from the Edo Period, what might be considered the Golden Era of Japanese Cartography, radiate outward from the center, so that to read the map, you would simply orient it to the direction you are facing. This has some practical advantages for getting around but was most useful only on smaller scale maps and city plans. In the Meiji period (late 19th century), European cartographic norms began to exert an influence on traditional Japanese Cartography. By the turn of the century, most Japanese maps had adopted a northerly orientation.

To recap, the convention of orienting maps to the north comes down to us from Ptolemy, for whom it was a practical choice given the style in which his maps were made, the extant of the world he attempted to cover, and the nature of his projection. While briefly abandoned in the middle ages, the northerly convention was re-established during the renaissance and reaffirmed with the advent of navigational cartography in the 16th century.

Related Maps in our Inventory:
http://www.geographicus.com/P/AntiqueMap/Fuji-edo-1843
http://www.geographicus.com/P/AntiqueMap/HolyLand-tirinus-1632
http://www.geographicus.com/P/AntiqueMap/Hokkaido-japan-1850
http://www.geographicus.com/P/AntiqueMap/Edo-japan-1849
http://www.geographicus.com/P/AntiqueMap/TerraeSanctae-funck-1720
http://www.geographicus.com/P/AntiqueMap/Bali-bellin-1760

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7 Responses to “The Arrow Points North: Directional Orientation in Antiquarian Cartography”

  1. Richard Wedekind says:

    Hi
    I have often wondered at the origin/use of the multiple roses of rhumb lines on old maps.

    I understand the concept of rhumb lines and great circles, but am intrigued by these apparently (to my eye) randomly distributed roses of radiating and intersecting lines.

    What was their purpose and what defined the location of multiple points of origin?

    Much appreciate any input.

    Cheers

    Richard.

    • Kevin Brown says:

      Richard,

      Rhumb lines are used by navigators to plot a course. Before navigators had the ability to identify their specific point on the map using special timers and astronomical observation they navigated using a technique called “Dead Reckoning.” What this means is they pointed their boat in a specific direction using a compass and stayed on this course for a number of days. The rhumb lines are meant to assist in this process. Their placement and the placement of multiple points of origin for radiating rhumb lines on a single map is based upon strategic practicalities specific to the intent of the individual map.

      Kevin

  2. Collin says:

    Hello,

    I’m writing a paper about directionality in cartography, and am very interested in some of the things you’re saying…

    Do you have a record of the sources you cited?

    Thanks!

  3. Samir elbaguer says:

    As a professional navigator I can assure you that the main reason that maps point north is that magnetic compasses point north and when they widely came into use It was logical to orient maps that way, since orienting them in any other direction would unnecessarily complicate course plotting.and navigation.

    • Kevin Brown says:

      Samir- While your simple assumption may seem obvious and certainly the development of the nautical chart and the use of the compass were highly influential on popularizing the convention of north-south orientation, a close examination of historic record reveals a much more complicated path of development. Many of the earliest nautical charts (15th – 17th centuries) were used for compass navigation and did not orient to the north. In fact, it was only much later in the development of the nautical chart that the north-south orientation system became a standardized convention. -Kevin

  4. [...] We are accustomed to looking at maps in which north is up and south is down (although the North Pole of maps does not quite coincide with the North Magnetic Pole, which complicates things a bit). Maps point north perhaps because they were invented by people in the Northern Hemisphere, who may have found it convenient because they used the North Star for navigation. If you look at the North Star while holding up a map in front of you, it helps to be able to read the labels on the map without having to tilt your head. According to some, the tradition of putting north up and south down dates back to Ptolemy. [...]

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