Maritime Magnetic Compass

Timeline

1. c. 1088–1200China's southeast coast · ChinaShen Kuo's Dream Pool Essays (c. 1088) recorded methods of grinding a south-pointing needle with lodestone, which Song navigators promptly applied to South China Sea trade routes. In the Southern Song, maritime compasses (wet and dry types) were widely adopted by merchant ships from Guangzhou to Southeast Asia, guiding ocean voyages alongside astronomical observation and laying the technical prototype for later global spread.
2. c. 1190–1350Mediterranean · MediterraneanEuropean documents first recorded the compass needle around the 1190s (in the works of Alexander Neckam); in the 13th century Genoese and Pisan sailors adopted the dry compass (including the compass rose wind rose) as standard equipment, used with portolan charts, greatly improving the safety and directional accuracy of Mediterranean winter and night sailing; the bussola gradually took shape.
3. 1511–1520Global oceans · OceansBetween 1511 and 1520, major voyages such as Portugal's conquest of Malacca (1511) and Magellan's circumnavigation (1519) all relied on the magnetic compass as the core navigational tool. Portuguese and Spanish navigators simultaneously confronted the practical problem of magnetic declination and began correcting it, advancing geomagnetism toward early scientific status; the Ming dynasty Zheng He navigation tradition likewise relied on compass-route charts (star-crossing charts) to navigate the South China Sea and Indian Ocean, forming parallel Eastern and Western compass navigation traditions.