成人快手

Melvyn Bragg and guests discuss the history of magnetism. Pliny the Elder, in his Historia Naturalis, tells a story of a legendary Greek shepherd called Magnes who, while guiding his flock on Mount Ida, suddenly found it hard to move his feet. The nails of his sandals held fast to the rock beneath them, and the iron tip of his crook was strangely attracted to the boulders all around. Magnes had stumbled across the lodestone, or 'Magnetite', and discovered the phenomenon of magnetism. Plato was baffled by this strange force, as were Aristotle and Galen, and despite being used in navigation, supposedly suspended over the body of Mohammed and deployed in the pursuit of medical cures. St Thomas Aquinas thought magnets had souls. it was not until the late 16th century that any serious scientific attempt was made to explain the mystifying powers of the magnet. Descartes developed a particle theory of magnetism but the great Isaac Newton fought shy of the problem of what caused magnets to attract and repelWho pioneered the study of magnetism? What theories did they construct from its curious abilities and how was the power of the magnet brought out of the realm of magic and into the service of science? With Stephen Pumfrey, Senior Lecturer in the History of Science at the University of Lancaster; John Heilbron, Emeritus Professor of History at the University of California, Berkeley; Lisa Jardine, Professor of Renaissance Studies at Queen Mary, University of London.