Heinrich Daniel Ruhmkorff (Rühmkorff) (15 January 1803 – 20 December 1877) was a German instrument maker who commercialised the

induction coil An induction coil or "spark coil" (archaically known as an inductorium or Ruhmkorff coil after Heinrich Rühmkorff) is a type of electrical transformer used to produce high-voltage pulses from a low-voltage direct current (DC) supply. p.98 To ...

(often referred to as the Ruhmkorff coil). Ruhmkorff was born in

Hanover Hanover (; german: Hannover ; nds, Hannober) is the capital and largest city of the German state of Lower Saxony. Its 535,932 (2021) inhabitants make it the 13th-largest city in Germany as well as the fourth-largest city in Northern Germany ...

. He changed the "ü" to "u" in his name when living abroad. After an apprenticeship with a German mechanic, he moved to England. Contemporaneous and extant biographies have made the assertion that he worked with the inventor

Joseph Bramah Joseph Bramah (13 April 1748 – 9 December 1814), born Stainborough Lane Farm, Stainborough, in Barnsley, Yorkshire, was an English inventor and locksmith. He is best known for having improved the flush toilet and inventing the hydraulic pr ...

, but this is unlikely since Bramah died in 1814. He may, though, have worked for the Bramah company. In 1855, he set up a shop in Paris, where he gained a reputation for the high quality of his electrical apparatus. Although Ruhmkorff is often credited with the invention of the

, it was in fact invented by

Nicholas Callan Father Nicholas Joseph Callan (22 December 1799 – 10 January 1864) was an Irish priest and scientist from Darver, County Louth, Ireland. He was Professor of Natural Philosophy in Maynooth College in County Kildare from 1834, and is best known ...

in 1836. Ruhmkorff's first coil, which he patented in 1851, utilized long windings of copper wire to achieve a spark of approximately 2 inches (50 mm) in length. In 1857, after examining a greatly improved version made by an American inventor,

Edward Samuel Ritchie Edward Samuel Ritchie (1814–1895), an American inventor and physicist, is considered to be the most innovative instrument maker in nineteenth-century America, making important contributions to both science and navigation. Early life and career R ...

, Ruhmkorff improved his design (as did other engineers), using glass insulation and other innovations to allow the production of sparks more than 30 centimetres long. Ruhmkorff patented the first version of his induction coil in 1851, and its success was such that in 1858 he becomes the first recipient of the

Volta Prize The Volta Prize (French: ''prix Volta'') was originally established by Napoleon III during the Second French Empire in 1852 to honor Alessandro Volta, an Italian physicist noted for developing the electric battery.John L. Davis. Artisans and savants ...

, 50,000 French franc award by

Napoleon III Napoleon III (Charles Louis Napoléon Bonaparte; 20 April 18089 January 1873) was the first President of France (as Louis-Napoléon Bonaparte) from 1848 to 1852 and the last monarch of France as Emperor of the French from 1852 to 1870. A nephew ...

for one of the most important discoveries in the application of electricity. He died in Paris in 1877. The Ruhmkorff lamps or 'Ruhmkorff's apparatus' mentioned in several of

Jules Verne Jules Gabriel Verne (;''Longman Pronunciation Dictionary''. ; 8 February 1828 – 24 March 1905) was a French novelist, poet, and playwright. His collaboration with the publisher Pierre-Jules Hetzel led to the creation of the ''Voyages extraor ...

's science-fiction novels''Journey to the Center of the Earth'' (1864), ''From the Earth to the Moon'' (1865), and ''20,000 Leagues Under the Sea'' (1869). relied on induction coils but were not developed by Ruhmkorff.

Asteroid

The

asteroid An asteroid is a minor planet of the inner Solar System. Sizes and shapes of asteroids vary significantly, ranging from 1-meter rocks to a dwarf planet almost 1000 km in diameter; they are rocky, metallic or icy bodies with no atmosphere. ...

15273 Ruhmkorff, discovered in 1991 by E. W. Elst, is named after Heinrich Daniel Ruhmkorff.

References

External links

with photographs accessed April 12, 2006 *
Spark Museum—Induction coils
{{DEFAULTSORT:Ruhmkorff, Heinrich Daniel 1803 births 1877 deaths 19th-century German inventors Burials at Montparnasse Cemetery Scientists from Hanover German emigrants to France

Asteroid

References

Further reading

External links