This rare map appeared in a French edition of Antonio de Ulloa and Jorge Juan's Relacion Historica del Viaje a la America Meridional..., a seminal work on South American geography, culture, and history written by the two scientists after nearly a decade spent exploring the continent. Spaniards Ulloa and Juan were appointed to the French Geodesic Mission to South America. The purpose of the mission was to measure a degree of meridian arc at the equator, and the chosen location for the measurements was Ecuador. The measurements would then be compared with similar measurements made near the North Pole, with the goal of determining the true shape of the earth.

This uncommon plan of the port and bay of Portobelo is oriented with north to the bottom left. The historic Portobelo Bay was a Spanish transfer point for gold and silver coming from South America. The city is shown in block plan format, with lettered keys identifying important locations in both French and German. There is good detail of the surrounding coastline and depth soundings are given in the bay.

References: Kapp (MCC-73) #73; cf. Shirley (BL Atlases) G.ULL-1a.

Condition: A

A crisp impression, issued folding on a sheet with a bunch of grapes watermark and a few minor spots of foxing.