Electromagnetism in the Encyclopaedias

The paper is based on a talk given to celebrate Ørsted’s discovery of electromagnetism in 1820. It gives a brief account of Ørsted’s life and work, before using the evidence of articles on electricity and magnetism in the Encyclopaedia Britannica to assess understanding of the connection between the two phenomena in the 20 years before Ørsted’s discovery, and the immediate reception of it.