600 BC - 1599
Timelines
Man’s awareness of and fascination with magnetism and electricity date back at least 2,600 years, to 600 BC. That’s when, as far as we know, the ancient Greeks first made mention of the mysterious properties. The philosopher Thales of Miletus observed that amber, when rubbed, attracts feathers and other lightweight materials. He noticed, too, that lodestone (magnetite) can attract iron. But a clear distinction between these two phenomena was not recognized.
For centuries, these phenomena intrigued great minds, from Pliny to Plato to St. Augustine. But true insight would continue to elude them. Thinkers from ancient times and the Middle Ages were often hampered by a lack of tools, a flawed approach to asking questions, religious beliefs or organizations that suppressed free inquiry, and entrenched ideas that veered them off course.
During much of this period, animism colored people’s view of the world. Thales, for example, believed the lodestone possessed a soul. Other ideas that may seem silly to us today were proposed during this time. Roman philosopher Lucretius, for example, speculated that particles emitted by the lodestone swept away the air between it and iron, thus attracting the iron via a kind of suction.
Much later, a somewhat more thoughtful approach was taken by Frenchman Pierre de Maricourt (Petrus Peregrinus), who in the 13th century experimented with a spherical lodestone and other items, then published his findings in “Epostolia de Magnete.” He was among the first to suggest exploiting the still poorly-understood property of magnetism to create a perpetual motion machine.
There was, however, a magnetic tool that came into use during this time that had a far wider impact on human history than Peregrinus’ imagined machine: the compass. The Chinese are widely credited with inventing it. The first written reference to compasses used in Chinese navigation dates to 1086, and it was later used by European mariners. However, the compass was used centuries earlier for other purposes. Called a "south-pointer," the simple device featured a ladle-shaped lodestone, as pictured, the handle of which always pointed south. This earliest incarnation of the compass was more of a spiritual than navigational tool, used to guide the direction of people's lives, not their steps.
Even more than navigational charts and other tools, the compass made possible the great sea voyages of this period. The device led Columbus to America, Vasco da Gamma around the horn of Africa and into India, and Ferdinand Magellan in his circumnavigation of the globe. It also led to significant scientific discoveries, including observations of the Earth’s magnetic poles and declination of its magnetic field.
Toward 1600, a few discerning minds were beginning to see magnetism and electricity as two distinct forces. This insight marked the first great intellectual leap in humankind’s understanding of these interrelated fields. But it would be close to 250 years before a fuller understanding emerged about this interrelationship, or that other types of electricity existed besides static electricity.
600 BC - 1599
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c. 600 BC
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Greek philosopher Thales of Miletus noted that amber attracts feathers and other lightweight materials when rubbed, the first historical reference to static electricity. He also experimented with the lodestone, or magnetite, and observed that it can attract iron.
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c. 100 BC
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Lodestones are utilized in the divining boards of fortune tellers in China.
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c. 50 BC
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In his long poem De Rerum Natura (“On the Nature of Things”), Roman poet and philosopher Lucretius relates the physical theory of Greek philosopher Epicurus, including his attempt at an explanation for the activity of the lodestone.
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1086
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Chinese astronomer and mathematician Shen Kua reports the use of magnetic compasses for navigation in Meng ch'i pi t'an (“Dream Pool Essays”).
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1180
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Alexander Neckam, an English monk, provides the earliest European account of the use of magnetic compasses by mariners in his text De utensilibus (“On Instruments”).
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1269
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The French crusader Pierre de Maricourt, also known as Petrus Peregrinus, carries out simple experiments with magnets and writes his Epistola de magnete (“Letter on the magnet”), in which he discusses compasses, magnetic poles and the ability of strong magnets to reverse the polarity of weaker magnets.
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1492
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During his voyage westward from Spain, Christopher Columbus reportedly observes that the declination of the magnetic needle of his compass changes midway across the ocean from easterly to westerly.
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1551
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Italian mathematician Girolamo Cardano recognizes that magnetism and the attraction of small objects to excited amber are distinct from one another.
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1581
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Robert Norman, a British compass maker, describes the inclination or dip of a magnetic needle in The Newe Attractive, having measured the angle with a device of his own invention called the dip circle.
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1588
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Italian geographer Livio Sanuto first notes the idea that the Earth has two magnetic poles.
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1600-1699