History of the compass

The compass is a special tool used for finding direction when traveling. It works like a magnetometer, showing which way is north, south, east, and west. The four main directions are shown on a part called the compass rose, with north at 0°, east at 90°, south at 180°, and west at 270°.

The story of the compass begins more than 2000 years ago in ancient China during the Han dynasty. The earliest compasses were made from a natural magnetized stone called lodestone. People in China called it the "South Pointing Fish" and used it to help guide their travels on land. By the 1100s, Chinese sailors began using compasses on ships for sea voyages.

Later, compasses made from iron needles became common in Europe and the Islamic world. These new compasses were filled with liquid, making them more accurate and easier to use. Today, compasses are still important tools that help people find their way in many places around the world.

Navigation prior to the compass

See also: Polynesian navigation

Before people had compasses, they used the sun, stars, and landmarks to figure out where they were when they were at sea. They also looked at things like the mud on the ocean floor, the way birds flew, and the patterns of the wind and waves to help guide them. Some ancient groups, like those in the Indus Valley, used special tools to measure angles between stars. The Norse people used a sun compass to find north, and on cloudy days, they might use special crystals to sense the sun’s direction. The compass changed all this because it let sailors know which way they were going even when they couldn’t see the sky or land. This helped them travel farther across the oceans, which led to more trade and big discoveries during the Age of Discovery.

Geomancy and Feng Shui

Main article: Luopan

The compass was invented in China during the Han dynasty between the 2nd century BC and 1st century AD. At first, it was not used for navigation but for special ways to arrange buildings and for fortune-telling by the Chinese. These early compasses were made with lodestone, a natural magnet that points toward the Earth's magnetic poles. People used these compasses to pick good places for houses and farms and to find special treasures. Later, during the Song dynasty, compasses were used to help with navigation.

Some scientists think that people in Mesoamerica may have used similar magnetic tools even earlier, around 1400–1000 BC, for arranging spaces and for special rituals. However, other researchers believe these items were part of decorations and not real compasses.

Early navigational compass

Early cultures used special stones called lodestones as simple compasses to help with navigation. The Chinese were among the first to use these for direction finding, starting as early as around 850. They used the compass for both land and sea travel.

In Europe, the first known written record of a compass appears in a book from 1190. Some historians think the compass may have traveled from China to Europe through traders or travelers, while others believe Europeans might have developed their own version independently.

The Chinese made early compasses by floating a magnetized needle in water, which always pointed south. Later, they also used a dry compass with a needle attached to a wooden turtle shape. In Europe, compasses evolved into the familiar box with a rotating needle, improving sea travel and allowing longer voyages during winter months.

The Muslim world also adopted the compass for navigation and even for finding the direction to Mecca for prayer. Different cultures adapted the compass in their own ways, helping people travel safely across oceans and lands.

Main article: Four Great Inventions, List of Chinese inventions, and History of science and technology in China

Dry compass

The dry mariner's compass has three main parts: a needle that can move freely on a pin, all inside a small box with glass on top, and a wind rose. The wind rose is attached to a magnetized needle so that it turns as the ship moves, always showing the direction the ship is heading. Later, compasses were often placed in a special gimbal mount to keep them steady even when the ship moves a lot.

Although scholars like the French Peter Peregrinus and the Egyptian Ibn Simʿūn described similar ideas long before, it was an Italian pilot from Amalfi named Flavio Gioja who is often credited with creating the compass most sailors used. He made the needle spin above a compass card, giving the compass its familiar look. We know about such compasses from writings as early as 1380, and even earlier records from 1318 mention portable compasses in boxes, showing that these dry compasses were already known in Europe by that time.

Bearing compass

A bearing compass is a special kind of magnetic compass that helps people find directions by lining up objects with a special line called the lubber line. There is also a surveyor's compass, which is used to measure directions very accurately and help make maps. These types of compasses have been used since the early 1700s.

Over time, compasses got smaller and lighter so they could be carried easily. In 1885, a new kind of compass was invented that had a special piece to look through, called a prismatic compass. Later, in 1902, another compass was made with a mirror to help see directions better, called the Bézard compass.

In 1928, a man named Gunnar Tillander from Sweden created an even better compass. He combined a compass and a tool for measuring angles on maps into one instrument. This new compass could be used both for finding directions outside and for measuring on maps. In 1932, Tillander and three brothers started a company called Silva, and they began making and selling these useful compasses to people who loved the outdoors and to the army.

Liquid compass

The liquid compass is a special kind of compass where the magnetized needle or card is placed in fluid. This fluid helps to stop the needle from swinging too much, making it easier to read and reducing wear and tear. A simple version of this compass was first shown by Sir Edmond Halley in 1690. Early liquid compasses were heavy and could be damaged easily, but they were useful on ships. These compasses were protected in a special case and could handle the movement of the ship.

The first practical liquid compass for ships was made by Francis Crow in 1813. Later, in 1908, the Royal Navy started using liquid compasses more widely. These compasses were also used in airplanes. In 1909, Captain F.O. Creagh-Osborne made a compass for airplanes using a mix of alcohol and water. In 1931, the Silva Company in Sweden made a compass that used liquid to help the needle settle faster. In 1933, Tuomas Vohlonen created a new way to fill and seal a compass with a special liquid, leading to the lightweight compasses we use today.

Gyrocompass

The first gyroscope for scientific use was created by the French physicist Léon Foucault in 1852. A gyrocompass was later patented in 1885 in The Netherlands. In 1906, a German inventor named Hermann Anschütz-Kaempfe built the first practical gyrocompass. This type of compass had two big benefits over regular compasses: it showed the true north direction and was not affected by certain metals, like the steel on ships. Because of this, it was used in many warships during World War I and in modern airplanes.

Non-navigational uses

Astronomy

In the 1200s, people used compasses to find important directions for studying the stars. A writer named Peter Peregrinus described three compasses for finding the middle point of the day and night sky. Later, a writer from Yemen explained how to use a compass to point toward Mecca, a holy place for many people. An Egyptian writer also wrote about a compass used for finding direction to Mecca, though it looked different from compasses we know today. In the 1300s, a Syrian inventor made a tool for telling time for prayers that used both a sundial and a compass.

Building orientation

People in Denmark used compasses when building churches in the 1100s. One out of every four churches from that time was turned a little bit from the usual east-west direction, matching how the Earth’s magnetic field was at that time.

Mining

Miners in a town in Italy began using compasses underground as early as the 1200s to help guide tunnels and mark areas for different mining companies. By the 1400s, miners in the Alps also started using compasses regularly. Soon after, a German miner wrote the first detailed book about using compasses underground.

Sun compass

A sun compass uses the Sun’s position in the sky to find directions, adjusting for where you are on Earth and the time of day. In places far from the equator, a watch can act as a rough sun compass, and a sundial works much better. A British officer created an automatic sun compass for use in tanks in India in 1938, but it could not be used when the sky was cloudy.

See also: Cardinal direction § Watch face, and Sundial § Using a sundial as a compass