Subject: biography, technology and manufacturing
German electrical engineer who discovered the dynamo principle and who organized the construction of the Indo-European telegraph system between London and Calcutta (now Kolkata) via Berlin, Odessa, and Tehran.
Siemens was born on 13 December 1816 at Lenthe, near Hannover. In 1832 he entered the Gymnasium in Lubeck. Three years later he became an officer cadet at the artillery and engineering school in Berlin, and studied mathematics, physics, and chemistry 1835-38.
As a serving officer he continued his studies and, in his spare time, he made many practical scientific inventions. He invented a process for gold- and silver-plating and a method for providing the wire in a telegraph system with a seamless insulation using gutta-percha. Other inventions included the ozone tube, an alcohol meter, and an electric standard or resistance based on mercury.
In 1847, Siemens founded with scientific instrumentmaker Johan Halske (1814-1890), the firm of Siemens-Halske to manufacture and construct telegraph systems. The company was responsible for constructing extensive systems in Germany and Russia. In 1870, the firm laid the London-Calcutta telegraph line and later became involved in underwater cable telegraphy. In the UK, Siemens became scientific consultant to the British government and helped to design the first cable-laying ship, the Faraday.
Valuing the contribution science was already making to technological advancement, Siemens helped to establish scientific standards of measurement and was mainly responsible for establishing the Physickalische-Technische Reichsastalt in Berlin in 1887. He was also cofounder of the Physical Society. His contributions to science were rewarded with a honorary doctorate from the University of Berlin in 1860. He was elected member of the Berlin Academy of Science in 1873 and was ennobled in 1888. In 1889 Siemens retired from active involvement with his firm. He died on 6 December 1892 in Charlottenberg.
Siemens's genius for invention was developed on a very wide scale through the firm he established in Germany with Halske and also through the firm of Siemens Brothers, which had been established in the UK. In 1846 he succeeded in improving the Wheatstone telegraph, making it self-acting by using ‘make-and-break’ contacts. He subsequently developed an entire telegraph system that included the seamless insulation of the wire. The firm obtained government contracts to provide extensive telegraph networks in Germany. But because of disagreements, these Prussian contracts were cancelled in 1850, so Siemens went to Russia and established an extensive telegraph network there - one that included the line used during the Crimean War.
His greatest single achievement was the discovery of the dynamo principle. Siemens announced his discovery to the Berlin Academy of Science in 1867. He had already introduced the double-T armature and had succeeded in connecting the armature, the electromagnetic field, and the external load of an electric generator in a single current. This enabled manufacturers to dispense with the very costly permanent magnets previously used. Unlike other workers in the field, including Charles Wheatstone, Siemens foresaw the use of his dynamo in machines involving heavy currents. This enabled his companies to become pioneers in the development of electric traction in such applications as streetcars and mini-locomotives and also of electricity-generating stations.
Again unlike some inventor-engineers of his time, Siemens valued the contribution that science could make to practical engineering advancement. He advocated that technique should be based on scientific theory. He often published analyses of his telegraph and cable-laying technology in reports to the Berlin Academy of Science. He also maintained that a nation, in times of harsh international competition, would never maintain its status in the world if it did not base its technology on continuing research work.
siemens , the metric unit of electrical conductance, is named after the German electrical engineer Ernst Werner von Siemens ( 1816 - 1892 ...
Siemens was the eldest of the four Siemens brothers and was educated at Lübeck, and later at the army engineering...