London: Royal Society of London, 1831. Wraps. First Edition. Article has been extracted from the original volume. 99-108 pp. 4to. Clean, crisp copy. Fine.
In 1831, shortly after Danish physicist Hans Christian Oersted (1777–1851) discovered electromagnetism, English mathematician and physicist Peter Barlow (1776 –1862) carried out an experiment that demonstrated that an electrical phenomenon could produce the earth’s magnetic field. This was the first precursor to the current dynamo theory of geomagnetism.