Christian Gottlieb Kratzenstein

Christian Gottlieb Kratzenstein ( born January 30, 1723 in Wernigerode, † July 6, 1795 in Frederiksberg) was a professor and naturalist.

Life

Christian Gottlieb Kratzenstein was born the second youngest son of the schoolmaster Thomas Andreas Kratzenstein in the small town of Wernigerode residence of the Counts of Stolberg am Harz. He attended secondary school in his native town, where his father taught. Even as a teenager, he led the Count Heinrich Ernst zu Stolberg before experiments with the electrical machine and often visited the chunks. The studies of the natural sciences, he began in 1742 at the University of Halle ( Saale).

In 1746 he earned a Master's degree and a doctorate. As a lecturer he taught subsequently at the University of Medicine and Natural Philosophy, but was followed by 1748 to teach at the Russian Academy of Sciences to Saint Petersburg. Since 1748 was Kratzenstein member of the Leopoldina, since 1753 the Royal Danish Academy of Sciences. In St. Petersburg he worked until 1753 as a professor of mathematics and mechanics, before he became professor of experimental physics at the University of Copenhagen, where he worked 33 years and four served as rector. Kratzenstein also spent his life in Denmark. However, when great fire of Copenhagen in 1795, he lost his comprehensive instrument and manuscript collection. A month later, he died in Frederiksberg, and was buried in St. Peter's Church. A portion of its assets, he endowed the chair of physics at the university.

Services

Kratzenstein dealt with at an early stage opportunities for the airship. He was also interested in astronomy, navigation, aviation, meteorology and alchemy. However, his special field of research was the effect of electricity on the human body. In this area it numerous discoveries are due to, for example, the Kratzenstein 's bubbles. Kratzenstein is co-founder of physical medicine using the electricity and designed one of the first electrostatic generators. The electro-therapy was being used by him early in patients.

Alongside he developed in 1780 in response to a question of price of the St. Petersburg Academy, a series of five reed pipes, which could each have a vowel ( namely A, E, I, O, U) produce synthetically. To this end, developed Kratzenstein, probably modeled after the Chinese mouth organ sheng, by beating reed pipes and is considered the first European "inventor" (rather well: discoverer ) of this particular reed pipes form, the principle of resounding tongue may have been discovered several times independently in the following decades.

Scratching the stone reed pipes had resonators with complex shapes, which, however, no relation to the anatomical conditions of the people were, but simply took the form after scratching the stone in his own words, with which they were their respective perform the best. Robert Willis had in 1832 in his article " From vocal tones and reed pipes " after that scraping stone Resonatorformen were completely unnecessary and resonators could just as well and better serves the same purpose in the form of different long cylindrical tubes.

Wolfgang von Kempelen developed a few years later, a " speaking machine", with it he was the first to produce words and shorter sentences. As reeds damped single reeds were used.

Honors

On 24 March 2011 the City Council of Wernigerode, a street in the commercial district decided " on smatvelde " by Christian Gottlieb Kratzenstein named.