Key Characteristics of Portolan Charts

CHAPTER 2 Key Characteristics of Portolan Charts

2.1 Preamble

Among the innovations introduced in the eleventh, twelfth and thirteenth cen- turies, portolan charts are among the most surprising; they constitute a very significant step forward in cartography. Certain aspects of these charts devel- oped over time and Campbell therefore limits his review of portolan charts to the period before 1500,1 whilst Pujades prefers 1470.2 Both do so for similar reasons: the character of portolan charts changes in the late fifteenth century and the coverage area was greatly expanded to include newly discovered terri- tories. Furthermore, European mapmaking changed as a result of the introduc- tion of astronomic navigation by the Portuguese, which resulted, for example, in the addition of latitude scales to the charts. Also the gradual replacement of manuscript charts on vellum with charts printed on paper influenced the map- ping style. Gaspar discusses these developments in his recent dissertation.3 But the characteristic wind rose of the early portolan chart (see Figure 2.1 below) continued to be a feature of nautical charts until well into the eighteenth century. The description of the key characteristics of Mediterranean portolan charts from the thirteenth to the end of the fifteenth century provided below is largely based on Campbell’s authoritative description. A short justification of the name to be used for these charts is, I believe, appropriate. Particularly in the early days of portolan chart research there was much debate on the name to be used. Several authors proposed a name that

1 Campbell 1987, 381. Campbell explains his reasons in his footnote 1 as follows: “first, the extension southward and eastward to include the Cape of Good Hope and the route to the Indies occurs close to that date, as does the first cartographic representation of Columbus’s discoveries; second, the earliest surviving charts to incorporate a latitude scale – and thus in some opinions to have outgrown the term ‘portolan chart’ – also date from the very first years of the sixteenth century . . .” 2 Pujades 2007, 412. Pujades chooses the year 1470 because around that year the Portuguese reached the equator, which signified “a milestone in the history of navigation and by extension, of nautical cartography”. 3 Joaquim Alves Gaspar, From the Portolan Chart of the Mediterranean to the Latitude Chart of the Atlantic. Cartometric Analysis and Modelling, PhD dissertation, Universidade Nova de Lisboa (2010): 21–32.

© koninklijke brill nv, leiden, ��6 | doi ��.��63/9789004285125_003 12 CHAPTER 2 implied a relationship with the compass (compass chart) or with a map projec- tion (loxodromic chart or rhumb line chart). Nautical chart was felt to be not descriptive enough. The term portolan chart was coined in the 1890s4 to reflect the consensus that still exists among most researchers regarding the relationship between the sailing guides known as portolans and the charts. Modern French scholars such as Patrick Gautier Dalché and Emmanuelle Vagnon reject such a relationship and refer to these charts as ‘cartes marines’, sea charts.5 The word portolan or portolano has also been used to describe the charts, but is nowadays avoided because it leads to confusion with the sailing guides. In this book I have followed common practice with the use of the term portolan chart, for no better reason than that it is well established. Moreover, as long as their origin and construction method is unclear, there appears to be no point in get- ting too hung up about terminology, provided it creates no confusion.

2.2 Distinguishing Characteristics

There is no doubt that these cartographic products are nautical charts rather than land maps, even though the majority of extant charts appears to have been created as objects of prestige and display, to be owned by wealthy mer- chants, princes, noblemen and even kings and never to be taken out to sea. Nevertheless, Pujades demonstrates6 widespread shipboard use of what was presumably an undecorated, purely utilitarian type of portolan chart. These would only have had a limited lifespan in an environment dominated by salt and water, the vast majority of which have not survived.7 Some authors have attempted to make a case for the existence of sea charts in antiquity, even

4 Campbell 1987, 375, main text and footnote 39. 5 Gautier Dalché 2001: 10, 15. Emmanuelle Vagnon, “La représentation cartographique de l’espace maritime”, La Terre. Connaissance, representations, mesure au Moyen Âge, ed. Patrick Gautier Dalché (Turnhout: Brepols Publishers, 2013), 445. 6 Pujades 2007, 428. Pujades presents a compilation of references to nautical cartography in medieval documentation covering the period from 1315 to 1531, “confirming the existence (not counting the Venetian examples from later than 1500) of over 220 complete charts, 8 partial charts and a further twenty or so other documents, including atlases, mappaemundi in panels, charts in panels or navigational tables.” 7 Tony Campbell pointed out that some may have survived and provides a shortlist of examples on his web forum http://www.maphistory.info/PortolanColourNotes.html#plain. One of them might be the Ristow-Skelton No. 3 chart, analysed in this book (Tony Campbell, per- sonal communication, 9/12/2012).