Portal de Periódicos da CAPES

Curious Vigias in Portolan Charts

1999; University of Toronto Press; Volume: 36; Issue: 1 Linguagem: Inglês

10.3138/q477-2101-7148-53l2

1911-9925

J. H. Kelley,

Maritime and Coastal Archaeology

Many small crosses, once called vigias, denoting hazards to navigation, appear on the late medieval portolan charts of the Mediterranean. The fact that most appear far at sea over abyssal depths has classed them as mariners' delusions. Indeed, "vigia" has been defined, perhaps partly in jest, as "Numerous imaginary dangers … traditionally inserted in all Ocean Charts" (OED). Perhaps. But considering that portolan charts are so pragmatic in other respects, could there be some underlying practical reality to explain their vigias? Using geophysical and anecdotal data, this paper suggests that the vigias of the portolans are not arbitrarily placed, but originate from observations of short-term, sometimes repeated, surface phenomena—shock waves, surface disturbances, smoke plumes, scoria, and so on—thrown up by seismic and volcanic disturbances on the Mediterranean's geophysically active sea floor.