Year of Invention: A.D. 83
What Is It? A device that aligns with the earth’s magnetic field and indicates
direction by always pointing north-south.
Who Invented It? Unknown (in China)
The compass revolutionized open water sailing by allowing accurate, all-weather open sea navigation. It opened the world to exploration.
Beginning in the thirteenth century, virtually every ship that left port had a compass. Almost every airplane ever built has had a compass. Many cars now feature built-in compasses. Every explorer, and almost every mountain hiker, has relied on a compass for direction and navigation.
For over 2,000 years the simple magnetic compass has been the most used and most successful direction-finding tool on Earth.
Before the invention of the compass, travelers walked from one landmark to the next. Sailors hugged coastlines—even for long voyages—using coastal features as markers. Some ventured into the open oceans using the polestar (North Star) by night and the sun by day as navigational guides. However, these markers were useless during periods of cloud cover, and many ships strayed far off course to their doom while waiting for the clouds to clear.
The principle of the compass was discovered first in China sometime around the fourth century B.C. There are also references to the magnetic property of certain stones in early Greek and Egyptian writings, but no indication that either group made significant use of compasses.
The Chinese discovered that thin chips of loadstone, a naturally occurring magnetic ore, would spin when suspended in water and always point south. Once discovered, this ability of loadstone was not used for navigation, but for feng shui. Chinese used the first compasses to align buildings, rooms, windows and furniture with nature according to the principles of feng shui.