Leopold Gmelin

Leopold Gmelin ( born August 2, 1788 in Göttingen, † April 13, 1853 in Heidelberg ) was a German chemist. Gmelin was a professor at the University of Heidelberg and worked among other things, potassium ferricyanide, the red prussiate of potash.

Life

Gmelin was a son of the physician, botanist and chemist Johann Friedrich Gmelin and his wife Rosine Schott. With his family he came early with medicine and the natural sciences in contact, 1804, he heard the chemistry lectures of his father. In the same year Gmelin went to Tübingen to work in the family pharmacy, he also studied at the University of Tübingen, among others, Ferdinand Gottlieb Gmelin ( a cousin ) and Carl Friedrich Kiel Meyer ( husband of a cousin ). With the support of Kiel Meyers Gmelin in 1805 moved to the University of Göttingen and was later assistant there in the laboratory by Friedrich Stromeyer. In 1809 he successfully passed his exams in the latter.

Leopold Gmelin returned to Tübingen and again heard the lectures of Ferdinand Gottlieb Gmelin and Carl Friedrich Kiel Meyer. In February 1811 Gmelin came with the medical students Gutike in dispute, according to an insult he called this to a duel, with glimpflichem output. Because duels were forbidden among students was thought the incident a secret, he nevertheless came to light. On March 10, Gmelin fled and went to Joseph Franz von Jacquin at Vienna University. Focus of Gmelin's research was among other things the Black pigment of oxen and calves eyes result of this work was also the subject of his dissertation. Gmelin in 1812 received his doctorate in Göttingen in absentia. Until 1813, he made ​​an extensive study trip to and through Italy. After his return he received the permission as a lecturer at the University of Heidelberg from the winter semester 1813/ 14 to work, first he made his Habilitation in Göttingen. On September 26th of the following year he was appointed associate professor in Heidelberg.

In the fall of 1814, he traveled study half to Paris at the Sorbonne, he remained until the spring of 1815. Together with his cousin, Christian Gottlob Gmelin he made ​​the acquaintance of René -Just Haiiy, Joseph Louis Gay -Lussac, Louis Jacques Thénard and Louis -Nicolas Vauquelin.

1816 married Gmelin in Kirchheim ( Heidelberg) Louise, a daughter of Kirchheimer pastor Johann Conrad Maurer; the jurist Georg Ludwig von Maurer was his brother in law. From this marriage produced three daughters and one son, including Auguste, the future wife of the physician Theodor von shower.

As a chemist Martin Heinrich Klaproth in 1817, died in Berlin, was supposed Gmelin succeed him. However, he refused and was sure Professor of Chemistry at the University of Heidelberg. There, a close cooperation with Friedrich Tiedemann evolved with time. The two published in 1826 " The digestion after tests " and thus laid the foundation of physiological chemistry. In the field of digestive chemistry Gmelin later discovered more components of the bile and introduced a bile pigment test named after him. When Friedrich Wöhler in 1822 worked on complex cyanogen compounds, assisted him Gmelin and discovered the red prussiate of potash.

From 1833 to 1838 was Gmelin owner of a paper mill in the north of Heidelberg located Schriesheim, he had taken over in the hope of profit. However, the work in the mill was very time and money consuming and at the expense of his academic activity.

Gmelin 1817 could publish the first volume of his Handbook of chemistry. 1843 the plant was grown in the fourth edition of nine volumes. In this edition of Gmelin took on the atomic theory, and devoted much more space to the increasingly important organic chemistry. The terms esters and ketones were introduced by Gmelin. Until his death Gmelin worked at the fifth edition of the handbook, which he has made himself worthy of the chemical information and documentation. He also laid the foundation stone for which was later named after him Gmelin system for the unambiguous classification of inorganic substances.

At the age of 60 years Gmelin suffered a first stroke, another in August 1850. Both strokes his right half of the body was made, he was able to recover from the paralysis, but remained weak. Gmelin asked in the spring of 1851 to his retirement, which was granted him. In the two following years he suffered increasingly from the effects of a brain suffering, with almost 65 years died Leopold Gmelin on 13 April 1853 in Heidelberg and found there on the mountain cemetery his final resting place. The grave complex is located in the Department of E. Here lie his wife Louise and more of kin.

Trivia

Work

Leopold Gmelin in his works dealt with the physiology, mineralogy and chemistry. His experimental work is marked by Gmelin's very thorough and comprehensive way of working, even some writing talent is attributed to him.

Gmelin's first physiological work was his dissertation on the black pigment of oxen and calves eyes whose coloring principle he tried to fathom. Despite the simplest chemical means he could take the properties of the pigment describe and recognize the carbon right as a cause of staining. Gmelin's most important physiological work is the 1826 released by digestion experiments which he made together with Friedrich Tiedemann. The work, described many new techniques, contained groundbreaking findings about the gastric juice in which they found hydrochloric acid, and the bile, in the Gmelin and Tiedemann, among others, discovered the cholesterol and taurine. Introduced by Gmelin Gallenfarstofftest enabled the detection of bile constituents in the urine of jaundice. Furthermore delivered Gmelin and Tiedemann, a new, more refined picture of the absorption of nutrients through the gastrointestinal tract, they were among the founders of modern physiology.

The mineralogical works Gmelins are analyzes of various minerals, such as the Haüyn with which he completed his habilitation in Göttingen, or Laumontits and the cordierite. In addition, Gmelin also analyzed mineral waters and published in 1825 the work test a new chemical mineral system, since he knew that the then usual division on outer or physical characteristics was inadequate. Leopold Gmelin mineral system was taken largely critical of the art but the basic idea of ​​order on the chemical composition proved to be useful.

Gmelin published the Handbook of theoretical chemistry, as Gmelin Handbook of Inorganic Chemistry in 1997 to about 800 volumes, produced by the Gmelin Institute, appeared and continued by the German Chemical Society as a database. The manual, as far back as his most important work was initially intended as a textbook, which should unite the whole former chemical knowledge. Due to the enormous increase in knowledge and the associated development of the handbook a reference book published Gmelin 1844, a compact textbook of chemistry. Its chemical achievements include the discovery of the crocodile acid, he had thus synthesized the first cyclic organic compound and the previously mentioned discovery of the red prussiate of salt.

In addition, Leopold Gmelin also developed a precursor of the Periodic Table and improved chemical equipment.

• Chemical investigation of the black pigment of the oxen and calves eyes, together with some physiological observations on the same, Dissertation, Gottingen 1812, in Latin. Schweiggers Journ. 10, pp. 507-547, 1814
• Oryktognostische and chemical observations on the Haüyn and some fossils occurring with him, along with geognostical remarks on the mountains of ancient Latium, Schweiggers Journ. 15 pp. 1-41, 1815; Ann. Phil Thomson 4, pp. 115-122; 193-199, 1814
• Leopold Gmelin, Friedrich Wohler: New cyanogen compounds, Schweiggers Journ. 36 pp. 230-235, 1822
• Trial of a new chemical mineral system, Paperback whole mineralogist. 19, I, p 322-334; 418-474; 490-507, 1825, II, p 33-77; 97-148, 1825
• Friedrich Tiedemann, Leopold Gmelin: The digestion after trials, Heidelberg and Leipzig, 1826, 2 vols
• Chemistry textbook for the use in lectures at universities, military schools, polytechnical institutes, secondary schools, etc., and to self lessons, Heidelberg, university bookstore Karl Winter, 1844