A compass is a technological marvel that led to some of the greatest discoveries in the history of mankind. It is a magnetic instrument that shows the directions north, south, east, and west. It uses the earth's magnetic field to point towards the North Pole based on which other directions can be marked easily. All you have to do is be able to know your right from your left.
Invention
The first magnetic compass was invented by the Chinese during the Han dynasty back in 206 BC. It was later adopted for navigational purposes by the Song dynasty during the 11th century and later in Western Europe and Persia in the 13th century. The Chinese were the first people to discover North America as well in 1421 and all types of other things that the Europeans claim credit for as well but this is another topic entirely.
Lodestone is a natural mineral ore which is also a fantastic conductor of magnets. The first compass was built using Lodestone (magnetized ore of Iron). Today the compass is built using liquid filled magnets.
Before the compass was discovered, travelers used their knowledge of sun and celestial bodies to determine their destination and direction. A compass made their life much easier as it would have been a difficult task to determine your direction on a cloudy or foggy night when you are unable to stargaze.
Though the Chinese discovered the compass way back in the 2nd century BC, they primarily used it for fortune telling and geomancy (form of divination). It was also used in construction to build houses and other structures based on feng shui.
The Chinese later discovered that the Lodestone when suspended in a way so that it could rotate freely on its axis would always point to one particular direction – north. It was not until the Song Dynasty in the 11th century, that the compass was adopted for navigation.
Interestingly, it was the Arabs that after coming into contact with the Chinese, introduced the lodestone based
magnetized compass to Europe. There was a lot trading done in India. India was often the middle ground between Europe and China.
Literature
The first literary proof of magnetized compass can be found in the works of Kuan Shih Ti Li Chih Meng or the Geomantic Instructor of Kuan in 880 AD. Another reference to the compass can be found in "Chung Hua Ku Chin Chu" written by Ma Kao who referred to it as the "Mysterious Needle".
One of the earliest compass was shaped like a spoon which was made from lodestone and placed on a flat surface. The spoon always pointed to the south. It was built during the Han Dynasty.
The Song Dynasty used lodestone "spoons" or "needles" for navigational purposes. They called it the south pointing fish in a bowl of water. Reference of this can be found in "Collection of the most important military techniques" written by Wujing Zongyao in 1040-44.
Present Scenario
The modern day compass is built using a liquid design in which the magnetized needle is dampened by liquid to reduce its wobbling and improve its readability. A capsule shape design is used which is completely filled with mineral oil or purified kerosene, and the magnetized needle is placed within this capsule. The directions and corresponding degrees are clearly marked using a dial which is placed below the needle to make it easy to identify direction faster and more accurately.
Human ingenuity continues to help out humankind in so many ways.