Carl August von Steinheil

Carl August von Steinheil (12 October 1801 – 14 September 1870) was an Alsatian physicist, inventor, engineer and astronomer.

Biography Reading telescopes by C.A. Steinheil purchased in 1865 on display in the Teylers Instrument Room Steinheil was born in Ribeauvillé, Alsace. He studied law in Erlangen since 1821. He then studied astronomy in Göttingen and Königsberg. He continued his studies in astronomy and physics while living in his father's manor in Perlachseck near Munich. From 1832 to 1849, Steinheil was professor for mathematics and physics at the Ludwig-Maximilians-Universität München.

In July 1839, Steinheil demonstrated a photographic process at Nymphenburg Palace in the presence of Queen Therese. Several photographs had been exhibited by Steinheil throughout April and Summer 1839. The process has been commonly attributed to Steinheil, but research published in 2024 revealed that the earliest paper negatives had actually been created by Wolfgang Franz von Kobell in 1837, without any involvement of Steinheil.

Steinheil was one of the first to use the daguerreotype in Germany. By December 1839, he made the first portable metal camera in the world. It was nineteen times smaller than the camera sold by Daguerre. At least ten of these cameras were manufactured.

In 1846, Steinheil travelled to Naples to install a new system for weight and measure units. Three years later, he was appointed to the Board of Telegraphy of the Austrian Trade Ministry. Steinheil was tasked with designing a telegraph network for the entire empire, and helped to form the Deutsch-Österreichischer Telegraphenverein (German-Austrian Telegraph Society). In 1851, he started the Swiss telegraph network. Steinheil returned Munich as konservator (curator) of the mathematical-physical collections and ministerial secretary in the Trade Ministry of Bavaria.

In 1854, he founded C. A. Steinheil & Söhne, an optical-astronomical company.

Steinheil died in Munich in Bavaria on 14 September 1870. He was buried in the Alter Südfriedhof cemetery.

Inventions

Ground electricity Print telegraph (not made public) Electric clock Steinheil script (code to print dots on paper via telegraph, not used due to the adoption of Morse code) Photographic process on silver chloride paper (together with Franz von Kobell) Steinheil doublet, a flint-first achromatic doublet Silver coating of curved glass surfaces (together with Léon Foucault) paving the way for the rise of reflecting telescopes.

Legacy Some sources state that Steinheilite, a transparent mineral that resembles blue quartz but is actually a form of iolite, was named after Carl von Steinheil.