What did Mariner's Magnetic Compass look like?

A circular card marked with 24方位 points (zi, chou, yin, mao, etc.). At the center, a magnetic needle (floating on water or pivoted on a point). Protected by a glass cover against wind and waves.

How did Mariner's Magnetic Compass work?

Magnetic needle rotates freely in the Earth's magnetic field → points north/south → the vessel's heading is read → compass方位 correspond to geomagnetic directions → combined with astronomical observations to correct for magnetic declination → maintains correct heading in overcast weather or on the open ocean with no landmarks.

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航海罗盘

Mariner's Magnetic Compass

A magnetic needle mounted on a compass card marked with 24 directional points for maritime navigation, enabling all-weather ocean voyaging and unlocking the Age of Exploration.

航海罗盘

Scientific Principle

Geomagnetic navigation: the horizontal component of Earth's magnetic field provides orientation. Magnetic declination correction: the angular difference between geographic north and magnetic north must be corrected using locally measured values.

航海罗盘

Mariner's Magnetic Compass

Scientific Principle

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