Heinrich Daniel Ruhmkorff (January 15, 1803 – December 20, 1887) was a German instrument maker who developed and commercialised the induction coil (often referred to as the Ruhmkorff coil.)

Ruhmkorff was born in Hanover. After an apprenticeship with a German mechanic he moved to England, where he worked with the inventor Joseph Bramah. 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 induction coil, it was in fact invented by Nicholas Callan in 1836. However, Ruhmkorff radically improved the design, using glass insulation and other innovations to allow the production of sparks more than 30 centimetres long. He first patented the coil in 1851, and its success was such that in 1858 he was awarded a 50,000-franc prize by Napoleon III for the most important discovery in the application of electricity. He died in Paris in 1887.

External links

• Biography with photographs accessed April 12, 2006

1803 births | 1887 deaths | German inventors

Heinrich Daniel Ruhmkorff | Heinrich Daniel Ruhmkorff | Heinrich Daniel Ruhmkorff