Photogravure after a photograph of Sir Charles William Siemens, originally Karl Wilhelm Siemens (1823-1883), German-born engineer and pioneer of the steel industry. In 1861Siemens, together with his brother Frederick (1826-1904), designed an open-hearth steel furnace, which was heated by gas produced from low-grade coal outside the furnace. This proces, first used in glas making, eventually replaced the Besemer proces (1856) in steel making. By the end of the 19th century more steel was produced by this method than any other. From a collection of portraits of scientists published by Photographische Gesellschaft, Berlin, c 1910. Dimensions: 460mm x 340mm.
© Science Museum / Science & Society Picture Library