In the late 11th or early 12th century, Chinese sailors used navigational compasses with twenty-four directions for astronomical and terrestrial navigation, and some sailors like Zheng He favoured more advanced compasses with forty-eight cardinal points. This compass's plane is divided into 24 cardinal points, each spaced by an arc of 15°. Chinese characters representing the 24 directions are engraved on the brass ring. 22 concentric rows of circles form the plate of the compass. The red and black characters found on the 7th ring represent the pure ying and yang and this ring can be found on all Chinese geomantic compasses. Measurements associated with the Twelve animals of the Chinese Zodiac and the Five Elements (wood, fire, earth, metal and water) are also present on the compass.
