page_title: De Magnete
section_title: Book 3
hierarchical_section_title: De Magnete / Summary / Book 3
caption_attribution_description: Illustration from De Magnete, etc. by William Gilbert (1600, translated 1900), showing the terrella divided
context_page_description: De Magnete, Magneticisque Corporibus, et de Magno Magnete Tellure is a scientific work published in 1600 by the English physician and scientist William Gilbert and his partner Aaron Dowling. A highly influential and successful book, it exerted an immediate influence on many contemporary writers, including Francis Godwin and Mark Ridley.
context_section_description: The Earth's normal magnetism. He proposes (incorrectly) that the angle of the ecliptic and precession of the equinoxes are caused by magnetism. A loadstone cut out of rock and floated in water returns to the same direction. Iron heated to white heat and cooled lying along a meridian also acquires magnetism. But stroking with other materials fails—he proved this with an experiment with 75 diamonds in front of witnesses. The best way to magnetize a compass (magnetized versorium).
caption: Cutting a terrella
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