1-157-653 - Oxford Science Archive/Heritage Images

Joseph Wilson Swan, British physicist and chemist, demonstrating electromagnetism, 1889. Swan (1828-1914) was the inventor of bromide paper for photography and of an incandescent light bulb. He is shown here at a Royal Society Conversazione, on 8 May 1889, demonstrating that a metal ring wound with a coil of wire rotates in the Earth's magnetic field when a small electric current is applied. From The Illustrated London News. (London, 1889).