Caspar Neumann (chemist)

Caspar Neumann or Kaspar Neumann (born July 11, 1683 in Züllichau , Brandenburg , † October 20, 1737 in Berlin ) was a German chemist and pharmacist . As a supporter of Stahl's phlogiston theory, Neumann brought it to bear in Berlin. He advocated a clear description of substances and substance components. He rejected concepts such as philosophical phosphorus .

Live and act

After Caspar Neumann's father, the businessman Georg Neumann, died in 1695, his godfather, the Züllichau pharmacist Johann Romcke, took care of him and introduced him to ars pharmaceutica ; at the same time he was receiving lessons in Polish from a preacher . In 1701, after completing his apprenticeship, Neumann went to the pharmacy in Unruhstadt, which belonged to Poland, as a temporary assistant at the age of 18.

In 1705 he moved to Berlin, where Neumann worked for a short time as a journeyman in the pharmacist Schmedicke's office and then moved to the farm pharmacy. His technical knowledge, but also his musical talents, paved the way for him to favor Friedrich I of Prussia . Friedrich gave Neumann a grant, which he used to perfect his chemical knowledge on educational trips. From 1711 onwards, he traveled to the Harz Mountains and other parts of Germany to get to know mines and ironworks, coins, laboratories, glassworks, foundries and botanical gardens. His travels took him to Holland, where he followed Herman Boerhaave's lessons in Leiden . Via Utrecht and Amsterdam he reached London, where in 1713 he received news of the death of his royal patron and at the same time of his dismissal (“ one no longer needs him ”).

In London he found a rich sponsor in the chemist Abraham Cyprianus († 1718), in whose private laboratory Neumann could work undisturbed. In 1716 he traveled to Germany in the retinue of King George I of England and negotiated in Berlin with the physician Georg Ernst Stahl (1659–1734), who campaigned for King Friedrich Wilhelm I to return to Berlin. With ample funds, Neumann returned to London. After the death of the Berlin pharmacist Memhard in 1718, he had to deal with his travel plans in a great hurry. Via Paris, where he came into contact with the brothers Étienne François and Claude-Joseph Geoffroy , Neumann traveled to Rome via Lyon, Grenoble, Turin, Genoa and Florence. From there he came back to Berlin in 1719 via Tyrol, Augsburg, Dresden and Leipzig. Here he was given the management of the farm pharmacy, which he held until his death.

In this position he used the knowledge he had acquired on his travels to completely reorganize the court pharmacy in Berlin. Within a very short time, through well-thought-out conversions and extensive modernization of the facility, he succeeded in developing the Berliner Hof-Apotheke into an exemplary pharmaceutical company, but above all into a research and training facility that had no counterpart in Germany. In the pharmacy's premises, it became possible to teach pharmaceutical chemistry for the first time. His many students also included the Nuremberg pharmacist Johann Ambrosius Beurer (1716–1754) and the pharmacist and chemist Andreas Sigismund Marggraf (1709–1782).

In 1723 Neumann was appointed to the Collegium medico-chirurgicum as the first pharmaceutical university professor and professor of practical chemistry. At the same time he received the position of chemist in the Berlin Academy of Sciences . When he was appointed to the upper medical college as a pharmaceutical assessor in 1724, he attended the practical examinations of the pharmacists and became the supervisor of all pharmacies in the Prussian state. Neumann actually developed the concept of the scientifically trained pharmacist.

Neumann also enjoyed a high reputation among his contemporaries as a scientist. He was a supporter of the phlogiston theory of his friend G. E. Stahl. He worked on thymol , ambergris , benzoin, cinnamic acid and the like. a., examined tea, wine, coffee and beer, was the first to recognize the acidic character of succinic acid and, 40 years before Carl Wilhelm Scheele, found "sweetened sublimate" as a reaction product of mercury solutions and table salt ( mercury (I) chloride or calomel as a mineral ) . In 1727 he was promoted to Dr. med. and the following year on March 1, 1728, with the academic surname Synesius, he was appointed a member ( matriculation no. 400 ) of the Leopoldina . The Royal Society in London also elected him a member in 1725. In 1723 he had previously told John Woodward in a letter the previously kept secret recipe for making Berlin blue , which Woodward then published in the Transactions of the Royal Society and was able to produce throughout Europe.

Even if there is no special individual achievement in the chemical or pharmacognostic field associated with his name, Caspar Neumann's merit lies in having scientifically raised the entire understanding of pharmaceutical activity. It was his achievement that after him enabled a time in which scientific interest increased and, as a result, important things were achieved in German pharmacy in the 18th century.

Services

• Demand for "clear material descriptions" of all components of a material (material analysis according to Georg Ernst Stahl). Neumann used approximate melting points and density for characterization .
• Approaches to a nomenclature (designation) of the salts.
• Works on thymol , rubbing alcohol , amber, benzoic and cinnamic acid .
• Experiments on the phlogiston theory.

Fonts

• Praelectiones Chemicae , 1749-1755
• Chimia medica dogmatico-experimentalis

literature

• Peter Berghaus u. a .: The doctor: graphic portraits of the 16th – 20th centuries Century from the portrait archive. Landschaftsverband-Lippe, Münster 1978, No. 85.
• Alfred Exner: The court pharmacist Caspar Neumann (1683-1737). A contribution to the history of the first pharmaceutical teacher at the Collegium medico-chirurgicum in Berlin. Dissertation, University of Berlin, 1938.
• Fritz Ferchl: Chemical-Pharmaceutical Bio- and Bibliographikon. Nemayer, Mittenwald 1938, p. 381 (detailed appraisal and listing of his numerous contributions).
• Karl Hufbauer: Neumann, Caspar . In: Charles Coulston Gillispie (Ed.): Dictionary of Scientific Biography . tape 10 : SG Navashin - W. Piso . Charles Scribner's Sons, New York 1974, p. 25-26 .
• Noretta Koertge: Complete Dictionary of Scientific Biography , 2008, entry Caspar Neumann.
• Wolfgang-Hagen Hein (Hrsg.): German pharmacist biography. 2 volumes. Wissenschaftliche Verlagsgesellschaft, Stuttgart 1975/78, Vol. 2, pp. 465-467.
• Christoph Heinrich Kessel: Life description D. Caspar Neumanns. In: Caspar Neumann: Chymiae medicae dogmatico experimentalis. Vol. 1, part 1. Johann Jacob Dendeler, Züllichau 1749 ( online ).
• Alexander Kraft: From the Züllichau orphan boy to the Royal Prussian court pharmacist in Berlin - The astonishing life story of Caspar Neumann (1683-1737). Yearbook for Brandenburg State History, Volume 66, 2015, pp. 111–141.
• Albert Ladenburg :  Neumann, Kaspar . In: Allgemeine Deutsche Biographie (ADB). Volume 23, Duncker & Humblot, Leipzig 1886, p. 535.
• Hermann Ludwig: Caspar Neumann (Biographical Monument). In: Archives of Pharmacy . Vol. 132 (1855), No. 2, pp. 209-217, doi: 10.1002 / ardp.18551320243 .
• Johann Daniel Ferdinand Neigebaur : History of the imperial Leopoldino-Carolinische German academy of natural scientists during the second century of its existence. Friedrich Frommann , Jena 1860, p. 211 (archive.org)
• Johann Christian Poggendorff (Hrsg.): Biographical-literary concise dictionary for the history of the exact sciences . Vol. 2 (1863), Col. 273 ( online ).
• Holm-Dietmar Schwarz:  Neumann, Caspar. In: New German Biography (NDB). Volume 19, Duncker & Humblot, Berlin 1999, ISBN 3-428-00200-8 , p. 156 f. ( Digitized version ).
• Otto Zekert: Famous Pharmacists. 2 volumes. Deutscher Apotheker-Verlag, Stuttgart 1955/62, vol. 2, p. 35 f.

Individual evidence

1. ↑ Member entry of Kaspar Neumann at the German Academy of Natural Scientists Leopoldina , accessed on December 22, 2017.
2. ↑ Alexander Kraft On two letters from Caspar Neumann to John Woodward revealing the secret method for preparation of prussian blue , Bull. Hist. Chem., Volume 34, 2009, Issue 2, pp. 134-140, pdf , with biographical information