Two items used by the English physicist Michael Faraday (1791-1867). The lodestone belonged to J F Daniell, a contemporary of Faraday and first Profesor of Chemistry at King's College, London. It was used by Faraday in 1831 to produce the first electric spark by electromagnetic induction using a natural magnet. Lodestones are naturally occurring magnets made of magnetite, an iron ore.
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