Johann Heinrich Pott

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Johann Heinrich Pott (born October 6, 1692 in Halberstadt , † March 29, 1777 in Berlin ) was a German doctor and chemist.

Life

The son of the royal Prussian councilor and canon in Halberstadt Johann Andreas Pott (1662–1729) and his wife, Dorothea Sophia, born in Machau, grew up in Halberstadt and studied theology at the University of Halle from 1709 , later with Georg Ernst Stahl and Friedrich Hoffmann medicine and chemistry. The study was interrupted for several years by Pott's participation in the Inspired Movement. Johann Heinrich and two of his brothers temporarily traveled through Germany as prophets of the Inspired Movement, but broke away from this sect in early 1715 and returned to Halle to study. After receiving his doctorate in 1716 on a purely chemical topic ( De Sulphuribus Metallorum ), Johann Heinrich Pott worked for a short time as a doctor in Halberstadt. In 1720 he settled as a doctor in Berlin, in 1722 became a member of the Societät der Wissenschaften and in 1724 professor of theoretical chemistry at the Collegium Medico Chirurgicum . Pott married a daughter of the wealthy businessman and commercial director Stanislaus Rücker . After the death of his friend Caspar Neumann , he also took over his professorship for practical chemistry (pharmacy) from 1737. As a chemist, Pott was a supporter of the phlogiston theory .

In 1753 there were public disputes about the replacement of the second chemistry professor position at the Collegium Medico Chirurgicum . Pott wanted to fill this position with his son-in-law Kurella. But it went to Brandes, a protege of Johann Theodor Eller , the influential First Royal Personal Physician. When Pott attacked Eller in a polemic, the Berlin scholars, above all Brandes, Johann Gottlob Lehmann and Andreas Sigismund Marggraf , sided with Eller. For this reason, and because of scientific disputes with his colleagues, for example with Marggraf about the conversion of water into earth, which Pott thought was not possible, he bitterly withdrew from the Academy of Sciences in 1754 . In 1770, Pott stopped giving lectures at the college because of his old age and weak eyes . However, he was still at the top of the list of lectures as an honorary member and gave private lessons in individual cases.

One of his students was Martin Heinrich Klaproth .

Services

  • Early - from 1713 - he used the borax and phosphorus beads for analytical purposes.
  • He recognized the difference between lead and graphite and thus carried out preparatory work to elucidate the nature of graphite.
  • Investigations and descriptions of bismuth (1739), brownstone (1740), zinc (1741) and zinc sulfate (1743, white vitriol). He is one of the co-discoverers of the elements bismuth, zinc and manganese .
  • Numerous studies on the production of porcelain on behalf of the Prussian government and on fire-proof vessels from 1740 to 1745. Pott never succeeded in reinventing Saxon porcelain , despite the approximately 30,000 attempts he carried out.
  • Pott is considered to be one of the founders of " pyrochemistry " with the investigation of the melting behavior of inorganic substances and mixtures from 1744 onwards.
  • His doctrine of the four basic earths ( calcareous-alkaline , sunny, pebbly, gypsum) contributed to the development of the concept of element.
  • In 1753 he found that succinic acid did not have the acidity of mineral acids.

Works

  • Exercitationes chymicae , 1738
  • Collectiones observationum et animadversionum chymicarum , 1739 and 1741
  • Lithogeognosia , several volumes and editions 1746–57
  • Chemical investigations, which deal principally with the lithogeognosia or knowledge and processing of the common, simpler stones and earth, the same of fire and light. Voss, Bremen 1757

swell

Individual evidence

  1. ^ Heinz Cassebaum : The position of the Braunstein investigations by JH Pott (1692–1777) in the history of manganese. In: Sudhoffs Archiv 63, 1979, issue 2, pp. 136–153.
personal data
SURNAME Pott, Johann Heinrich
BRIEF DESCRIPTION German chemist and pharmacist
DATE OF BIRTH October 6, 1692
PLACE OF BIRTH Halberstadt
DATE OF DEATH March 29, 1777
Place of death Berlin