Search

Nautical charts like this are detailed around the coasts and on the seas (e.g. river mouths, islands, shoals and reefs) while the interiors are blank. The web of lines is a rhumbline network, while the numbers indicate sea depth (bathymetry).

Maritime routes had to be adjusted in response to the changing monsoon seasons, as is seen on this late 18th century map of the Indian Ocean. Drawings of the heads of children blowing—called ‘wind-heads’—are used to indicate wind direction.

Navigation chart of the Sunda Strait, showing bathymetry (sea depth), shoals and reefs, landmarks, and a rhumbline network. Notes record good anchorages, sources of water and supplies etc. Inset map of the Zutphen Islands off the coast of Sumatra.