Discovery and Development
Main article: History of electromagnetism See also: Magnetism history
Ancient people learned about magnetism from lodestones, naturally magnetized pieces of iron ore. They are naturally created magnets, which attract pieces of iron. The word magnet in Greek meant "stone from Magnesia", a part of ancient Greece where lodestones were found. Lodestones suspended so they could turn were the first magnetic compasses. The earliest known surviving descriptions of magnets and their properties are from Greece, India, and China around 2500 years ago. The properties of lodestones and their affinity for iron were written of by Pliny the Elder in his encyclopedia Naturalis Historia.
By the 12th to 13th centuries AD, magnetic compasses were used in navigation in China, Europe, and elsewhere.
Read more about this topic: Magnet
Famous quotes containing the words discovery and/or development:
“That the discovery of this great truth, which lies so near and obvious to the mind, should be attained to by the reason of so very few, is a sad instance of the stupidity and inattention of men, who, though they are surrounded with such clear manifestations of the Deity, are yet so little affected by them, that they seem as it were blinded with excess of light.”
—George Berkeley (1685–1753)
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—Lawrence Kutner (20th century)