The Representation of Navigational Hazards: The Development of Toponymy and Symbology on Portolan Charts from the 13th Century onwards

The Journal of the Hakluyt Society The Journal of the Hakluyt Society December 2020 The Representation of Navigational Hazards: The Development of Toponymy and Symbology on Portolan Charts from the 13th Century onwards Tony Campbell and Captain M. [...] It will comment on the accuracy of the notification of those, assess the possible sources, and offer a judgment of the significance of the depicted dangers for the chart-maker and the users afloat. [...] Although the nature of the danger is left unspecified, it is placed, with reasonable accuracy – in terms of the respective directions and distances in the ‘miles’ of the time (milliaria) – in relation to Trapani on Sicily’s west coast and Isola Marettimo west of that, as well as to Tunisia’s Cape Bon and the island of Gimari (Djamour El Kébir) in the Gulf of Tunis (lines 2255-67). [...] The portolan chart-makers wisely made no attempt to plot the various detailed configurations of the two main deltas in the Mediterranean, the Rhône and Nile, nor the two largest in the Black Sea, the Danube and the Dnipro. [...] Yet it is here that most of the vigias on the portolan charts are shown, rather than in the Tyrrhenian Sea, described in the Admiralty Pilot as ‘amongst the principal seismic regions of the world’, where seamounts of volcanic origin extend from the Isole Eolie to the latitude of Vesuvius.