The Chinese discovered the magnetic compass as early as 200 BC. At first fortune-tellers used it. Later people realised that it was a way to find the direction of North and South.

The ancient Greeks knew that the lodestone or magnetite attracted iron towards it. It is known that the Vikings used a lodestone to navigate. Later at the end of the twelfth century Europeans were using this simple compass to aid navigation.

During the 16^th century Sir William Gilbert discovered that the properties of the lodestone could be transferred to ordinary pieces of iron by rubbing them with a lodestone.

What is a Magnet?

The first magnets were made of iron. These days they are:

• alloy magnets that contain metals such as

iron

nickel

copper

cobalt

aluminium

• ceramic magnets that are made from powders called ferrites which contain iron oxide and barium oxide.

Permanent magnets do not readily lose their magnetism.

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