Of the 11 known cartographers, many were pilots by profession and natives of the port of Dieppe. Their existing cartographic works – about 40 documents, all in manuscript form – were produced over the course of about one century (1542-1635). Besides the fine world maps drawn according to the most advanced projections of the period (like the sinusoidal projection of Jean Cossin’s 1570 map) and the marvelous, richly illuminated cosmographies speculating on lands “as yet undiscovered” (like the 1555 Cosmographie universelle by Guillaume Le Testu), most of the maps produced by these hydrographers were intended for navigation. Among them is a series of maps of the Atlantic Ocean, constructed, like portolan charts, using a network of rhumb or wind lines (giving the directions of the compass).
In 1601, Guillaume Le Vasseur (d.1670) became the first Norman hydrographer to employ the Mercator projection, a mathematical method of representing the globe as a flat surface, which allowed maritime travel to be represented as straight lines. He was also the first to correct the alignment of the Mediterranean Sea and the North American coast by accounting for the effect of magnetic declination on existing measurements.
Certain geographic motifs were characteristic of the Norman hydrographers, especially for North America: Labrador was shown as a peninsula, with its tip pointing east; Newfoundland was drawn as an archipelago; the Bay of Norembègue cut into the southern coast of Nova Scotia. Furthermore, certain maps reflected political claims to the newly explored lands. The 1566 world map by Nicolas Desliens used a French flag to mark the three zones of French settlement in the Americas in the 16th century: Canada and the “Land of Labrador,” the “May River” in Florida, and the “River Plate” in Brazil. Although it came much later, the magnificent map by Pierre de Vaulx (1613) persisted in marking the Florida coast and “Antarctic France” in Brazil as French territory.


Published in may 2021