China’s Contribution to Maritime Technology

The Chinese are responsible for some of the most important seafaring technology. Not only did the Chinese bring together the largest fleet ever to sail the ocean (under the command of Zheng He), but they also invented the magnetic compass. The Chinese were definitely aware of the concept of magnetism by the year 240 BCE, although some houses that were built as early as the 1700s BCE line up with magnetic north, and this has led some scholars to believe that magnetism was used even earlier. When Time Magazine listed its “Most Important Events of the Millennium,” a description of the invention of the compass was included:

It was little more than a magnet floating in a bowl of water, but without the nautical compass the millennium’s great voyages of discovery could never have occurred. First used in feng shui (the Taoist system of environmental design), compasses appeared in China in the fourth century BC. Lodestone pointers were replaced by flat slivers of iron, and then by needles, which arrived in the sixth century AD. But the first account of seagoing compasses doesn’t come until 1117, from Zhu Yu’s Pingchow Table Talk: “In dark weather, sailors look at the south-pointing needle.” The compass reached Europe around 1190, almost certainly from China. (Its powers were so little understood that captains forbade their crews to eat onions, which were thought to destroy magnetism.) For Mediterranean sailors, used to long periods when overcast skies made navigation difficult, the device meant liberation. By the fifteenth century, they were ready to venture beyond familiar seas.

The first confirmable record of a water compass used for Chinese maritime navigation comes from a book written c. 1125 CE. During the time of Zheng He, “Yang” water (seawater taken from the upwind side of the ship) was used in the compass. The magnetized needle was in the shape of a flat fish. The idea of the magnetic compass had made its way to Europe by 1190 CE, a fact that can be confirmed by its mention in a French poem. However, it would be another three centuries before European navigators would fully understand and use navigation by magnetic compass.