
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.
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Melvyn Bragg and guests discuss Renaissance Mathematics. As with so many areas of European thought, mathematics in the Renaissance was a question of recovering and, if you were very lucky, improving upon Greek ideas.…
Melvyn Bragg and guests discuss perception: how the brain reacts to the mass of data continually crowding it. Barry Stein's laboratory at Wake Forest University in the United States found that the shape of a right angle…
Melvyn Bragg and guests discuss 'dark energy'. Only 5% of our universe is composed of visible matter, stars, planets and people; something called 'dark matter' makes up about 25% and an enormous 70% of the universe is…
Melvyn Bragg and guests discuss the history of Alchemy, the ancient science of transformations. The most famous alchemical text is the Emerald Tablet, written around 500BC and attributed to the mythical Egyptian figure…
Melvyn Bragg and guests discuss the Cambrian period when there was an explosion of life on Earth. In the Selkirk Mountains of British Columbia in Canada, there is an outcrop of limestone shot through with a seam of fine…