Heinrich Daniel Ruhmkorff (Rühmkorff) (January 15, 1803 in Hanover – December 19, 1877 in Paris) was a German instrument maker who commercialised the induction coil (often referred to as the Ruhmkorff coil.)
Ruhmkorff was born in Hanover. He changed the "ü" to "u" in his name when living abroad. After an apprenticeship with a German mechanic, he moved to England. Biographies say that he worked with the inventor Joseph Bramah, 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.
He died in Paris in 1877.

(http://en.wikipedia.org/wiki/Heinrich_Daniel_Ruhmkorff)

(https://ia700707.us.archive.org/12/items/inductioncoilsho00schn/inductio...)