|MadSci Network: Science History|
Chris - Actually, no one discovered the Earth's magnetic field exactly. The effects of the magnetic field were noted as long ago as ~200 B.C. by Chinese fortune tellers who used primitive compasses made with lodestone to align their fortune-telling apparatus. By A.D. 800-1000, the Chinese were using compasses as navigation aids - an accomplishment that did not appear in Europe until the 1500s. However, none of these users realized why their compasses worked.
English scientist William Gilbert pioneered research into magnetism and electrical attractions. In 'De Magnete' (1600), he was the first to describe the earth's magnetic field and to postulate the relationship between electricity and magnetism. (He introduced the term 'electricity'). He corrected described the Earth as being like a giant bar magnet.
German scientist Carl Gauss is usually credited with being the first to make detailed observations of the field's direction and strength around 1840.
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