Ernst Werner von Siemens

Ernst Werner von Siemens (known as Werner von Siemens) (December 13, 1816 – December 6, 1892) was a German inventor and industrialist. Siemens' name has been adopted as the SI unit of electrical conductance, the siemens.

Early years
Werner Siemens was born in Lenthe, today part of Gehrden, near Hanover, Germany, the fourth child (of fourteen) of a tenant farmer. He is a brother of Carl Heinrich von Siemens and William Siemens, sons of Christian Ferdinand Siemens (July 31 1787-January 16 1840) and wife Eleonore Deichmann (1792-July 8 1839). They had two more brothers, Hans Siemens (1818-1867) and Friedrich August Siemens (December 8 1828-May 24 1904), married and father to Friedrich Carl Siemens (January 6 1877-June 25 1952 in Berlin), married on May 22 1920 in Berlin to Melanie Bertha Gräfin Yorck von Wartenburg (February 1 1899 in Klein Oels-May 15 1950 in Berlin) (the parents of Heinrich Werner Andreas Siemens (born September 28 1921, Annabel Siemens (born May 3 1923), Daniela Siemens (born July 31 1926) and Peter Siemens (born November 8 1928).

Middle years
Siemens left school without finishing his education, but joined the army to undertake training in engineering. Siemens invented a telegraph that used a needle to point to the right letter, instead of using Morse code. Based on this invention, he founded the company Telegraphen-Bauanstalt von Siemens & Halske on October 1, 1847, with the company taking occupation of its workshop on October 12.

Soon after its founding the company internationalised. One brother of Werner represented him in England (Sir William Siemens) and another in St.Petersburg, Russia (Carl von Siemens), each earning separate recognition in their own right. Following his industrial career, he was ennobled in 1888, becoming Werner von Siemens. He retired from his company in 1890 and died in 1892.

The company, reorganized as Siemens & Halske AG, Siemens-Schuckertwerke and – since 1966 – Siemens AG was later led by his brothers, his three sons Arnold, Wilhelm and Carl Friedrich and his nephews Hermann, Ernst and Peter von Siemens. Siemens AG is still one of the largest electrotechnological firms of the world.

Later years
Apart from the pointer telegraph Siemens made several contributions to the development of electrical engineering and is therefore known as the founding father of the discipline in Germany. His company produced the tubes with which Wilhelm Conrad Roentgen investigated x-rays. He claimed invention of the dynamo although others invented it earlier. On December 14, 1877 he received German patent No. 2355 for an electromechanical "dynamic" or moving-coil transducer, which was adapted by A. L. Thuras and E. C. Wente for the Bell System in the late 1920s for use as a loudspeaker. Wente's adaptation was issued US patent 1,707,545 in 1929. Siemens is also the father of the trolleybus which he initially tried and tested with his "Elektromote" on April 29, 1882.

Personal life
He married twice, first in 1852 to Mathilde Duman (died July 1 1867) and second in 1869 to his relative Antonie Siemens (1840 - 1900). Children from first marriage were Arnold von Siemens and Georg Wilhelm von Siemens. Children from second marriage were Hertha von Siemens (1870 - January 5 1939), married in 1899 to Carl Dietrich Harries and Carl Friedrich von Siemens.

Patents

 *  -- Electric meter