Question

How was lodestone (Magnet) invented ?

Answer 1

The lodestone is an extremely rare form of the mineral magnetite (Fe3O4) that occurs naturally as a permanent magnet. It therefore attracts metallic iron as well as fragments of ordinary magnetite. This ‘magic’ property was known to many ancient cultures. By the eleventh century AD the Chinese had discovered that a freely suspended elongated lodestone would tend to set with its long axis approximately north–south, and utilized this property in the magnetic compass. They also appear to have discovered that this invaluable characteristic could be handed‐on to a steel needle if the latter were contacted with, or stroked by, a lodestone.The magnetism of the lodestone was scientifically investigated by William Gilbert in the sixteenth century, when he defined its ‘poles' and the well‐known rule that ‘like poles repel, unlike attract’.