Compass Maritime Navigation Techniques

Timeline

1. 1161–1166Sea ports such as Quanzhou in Fujian and Guangzhou · Fujian CircuitIn the 1160s, coastal merchant vessels set up wet or dry compasses on deck or in cabins, with magnetic needles indicating north and south. Navigators recorded needle routes—the bearings to take on each leg—forming transmissible maritime knowledge and reducing reliance on single landmarks and star-gazing on clear nights.
2. 1167–1170Sea routes from the Chinese coast to Southeast Asia and South Asia · South China SeaBy around 1170, compass navigation supported Southern Song routes to Champa, Srivijaya, and more distant ports. Compasses were used alongside star-height measurement and hydrographic observation, improving night and fog navigation and providing key technical support for overseas trade under the Maritime Trade Supervisorates.