Read Online Man of Misconceptions : The Life of an Eccentric in an Age of Change (9781101597033) by John Glassie - Free Book Online Page A

this had the potential to impress: here was true natural magic. As opposed to astral influence, devil incantation, godly intervention, and other invisible forces whose existence could only be assumed, magnetism, an invisible and apparently immaterial power, produced very real, reliable effects on the material world. It was believed by many to function, on earth and everywhere, almost as a living spirit.
    As a thirteenth-century tract had it, for example, the lodestone “restores husbands to wives and increases elegance and charm in speech.” It also cured “dropsy, spleen, fox mange, and burn.” Magnetic plasters, made from shavings of iron or lodestone, were commonly applied to the body to draw out ill humors; magnets themselves were swallowed to draw them up from within. A kind of magnetic attraction, or sympathy, was also assumed to be behind the widely accepted healing action of weapon salve, used to treat men wounded on the battlefield. To make it, blood or tissue of the victim was mixed into the salve and then applied—to the
weapon
that had injured him. It was supposed to heal the wound from almost any distance. For his part, the Renaissance magus Paracelsus had promulgated the notion that disease and illness could be transferred “magnetically” to a lower life-form—that gout, for instance, could be drawn away by taking the afflicted person’s toenails and implanting them in the trunk of a tree.
    In 1600 a physician in the court of Queen Elizabeth of England published what is often called the first real work of experimental science, on this same subject of magnetism. In the Latin text of
De Magnete
(
On the Magnet
), William Gilbert explained how he systematically tested and debunked many commonly held notions about the lodestone. It wasn’t true, for instance, that if a magnet was “anointed with garlic” it ceased to attract iron. To check the claim made by della Porta in
Natural Magic
that diamonds can magnetize iron, Gilbert conducted “an experiment with seventy excellent diamonds, in the presence of many witnesses, on a large number of spikes and wires, with the most careful precautions.” It didn’t work.
    Gilbert’s investigations resulted in a great deal of real information about the actual properties of magnets and how they behaved. When it came to questions about what magnetism
was
or how it worked, however, he took a more spiritual turn. (In some senses it was an Aristotelian-sounding turn, but it was made in the direction of Copernicus.) Gilbert concluded that a “stupendous implanted vigour”—“very like a soul”—was responsible for magnetic action and attraction, and that the earth itself was a giant magnet. He used a magnetic sphere he called a terrella, a “little earth,” to perform his experiments. When the terrella was set at an angle toward the plane of another magnet, for example, it rotated. Gilbert believed the sun, “the chief inciter of action in nature,” brought about the rotation of Earth in a similar way: Earth’s “astral magnetic mind” responded when the sun sent forth its living energies, rotating steadily for uniform access to the vitality of its rays.
    This idea influenced Kepler, who wrote that he “built all Astronomy” on the work of Copernicus, Brahe, and Gilbert, and adopted the notion of a sun that emanated a magnetic force, causing the planets to move. Magnetism seemed to explain why the planets traveled in elliptical orbits, as he’d correctly calculated. According to Kepler, “the variety of all planetary motions derives from a very simple magnetic force just as all the motions of a clock derive from a simple weight.” Galileo was also influenced by the idea, and used the analogy of magnetism to explain why Earth held its axis through daily and annual motions.
    Kircher’s own work with magnetism extended beyond parlor tricks. In