Charles‑Louis Gressier ( 1791 -1886 )

French naval hydrographer, engineer, and mapmaker known for producing detailed nautical charts and hydrographic world maps for the French Navy.

Born in 1791, Gressier served as an ingénieur hydrographe (hydrographic engineer) with the French naval mapping service, the Dépôt général de la Marine. His work focused on maritime cartography, coastal surveys, and navigational charting during a period when European naval powers were expanding scientific and commercial exploration.

Gressier participated in important hydrographic expeditions along the coast of Brazil in 1819–1820 under the command of French naval officer Albin-Reine Roussin. Together with fellow hydrographer Alexandre Givry, he surveyed Brazilian ports, bays, and coastal waters, producing charts that improved navigation and maritime knowledge of South America.

His charts were valued for their precision and were used by navigators, naval officers, and geographers throughout the c.19th century.