Hans Christian Orsted, Danish physicist, c 1830.
© Science Museum / Science & Society Picture Library
Engraving. In 1820 Hans Christian Orsted (1777-1851) discovered the relationship between electricity and magnetism by setting up a very simple experiment; he demonstrated that a wire carrying a current could deviate a magnetised compass needle by ninety degrees. Whilst unable to suggest a satisfactory explanation for this phenomena, his discovery did bring about the study of electromagnetism by others. In 1825, he became the first person to produce aluminium by isolating it in a powdered form.