ABSTRACT
Medieval mappaemundi were generally the outcome of an erudite tradition upheld by thinking landsmen with an essentially ‘terrestrial’ conception of the world. Portolan charts are usually understood to have issued from the practical experience of Mediterranean sailors. The Majorcan artefacts were mostly created by Jewish cartographers of North-African origin in the context of, essentially, a merchant and maritime society. A major difference which remains between the general logic applied to mappaemundi and portolan charts is the absence of speculation about the geography of central and southern Africa in the latter works. Portolan charts and mappaemundi are in fact cartographic traditions that are less strange to one another than modern historians have tended to admit. Some attempts to extend the range of the ‘normal portolan’ are already noticeable from the first Catalan-style charts. The eastern arm of the Nile is named ‘Gion’ and is said to flow from Paradise ever since the time of earliest Catalan-style charts.
