orig. Karl Wilhelm Siemens
born April 4, 1823, Lenthe, Prussia
died Nov. 19, 1883, London, Eng.
German-born British engineer and inventor.
He immigrated to Britain in 1844. In 1861 he patented the open-hearth furnace (see open-hearth process ), which was soon being widely used in steelmaking and eventually replaced the earlier Bessemer process . He also made a reputation and a fortune in the steel cable and telegraph industries and was a principal in the company that laid the first successful transatlantic telegraph cable (1866). His three brothers were also eminent engineers and industrialists (see Siemens AG ).