Georg Hermann Quincke was a prominent German physicist. He is remembered for his important work in the experimental study of the reflection of light, especially from metallic surfaces. He also carried on prolonged researches on the subject of the influence of electric forces upon the constants of different forms of matter, modifying the dissociation hypothesis of Clausius.
Background
Georg Hermann Quincke was born on November 19, 1834, in Frankfurt (Oder), Brandenburg, Germany. He was the son of prominent physician Geheimer Medicinal-Rath Hermann Quincke and the older brother of physician Heinrich Quincke. His mother, Marie Gabain, came from a Huguenot family. In 1843 the family moved to Berlin, where the father was promoted to a medical council.
Education
After graduating from the Werder Gymnasium, Quincke began to study physics at the University of Berlin at the age of eighteen. He continued his studies at Konigsberg under Franz Neumann and then under Gustav Kirchhoff at Heidelberg. At the same time, Quincke worked in the laboratory of Robert Bunsen. He then returned to Berlin, where he received his doctorate in 1858 with a dissertation on the capillary constant of mercury.
Career
After receiving his doctorate in 1858, a year later Quincke obtained the venia legendi, for which he did not have to fulfill the usual requirement of presenting special Habilitationsschrift. He began teaching physics in 1859 at the Berlin Gewerbeakademie (the predecessor of the Technische Hochschule), and in 1865 he became an extraordinary professor at the University of Berlin.
In 1872 Quincke was appointed full professor at the University of Wurzburg, and in 1875 he succeeded Kirchhoff at Heidelberg. Following his retirement at the age of seventy-three, Quincke worked in his private laboratory at his country house.
During his lifetime Quincke was held in high regard by his peers, especially in England, where his friends included William Thomson, J. W. Strutt, Stokes, Tyndall, and Tait.
In 1859 Quincke discovered the so-called diaphragm currents. Above all, however, he was passionately interested in making measurements; and the bulk of his work consisted of the determination and collection of data concerning the properties and constants of materials. He frequently returned to capillarity, the subject of his doctoral dissertation. He found countless opportunities for research in extending the capillary-tube and angle-of-contact methods of measuring from simple liquids to solutions and fusions and in measuring interfacial tension between two liquids.
Quincke devoted a group of sixteen studies to problems in optics, basing his work on theories that viewed light as elastic vibrations in a mechanical medium. Between 1880 and 1897 he published the fifteen installments of his “Elektrische Untersuchungen,” dealing with the behavior of materials in electrostatic and magnetic fields. In this connection, Quincke developed his elegant meniscus-displacement method of determining diamagnetic and paramagnetic susceptibilities of liquids and gases. During the final years of his life, he was concerned primarily with foams and their structures.
Quincke introduced the first practical laboratory work to be given in a physics course at a German university. The restricted means at his disposal obliged him to get along with little, and the students spoke jokingly of “Quincke’s Cork-wax-penny System.”
Views
Quincke’s views on physics were rooted in the thought of the first half of the nineteenth century. He admired Faraday’s method of working and ideas, but he never understood Maxwell’s elaboration and mathematical reformulation of Faraday's discoveries.
Membership
Quincke was elected an honorary fellow of the Royal Society of London. He was also a member of the Prussian Academy of Sciences, Bavarian Academy of Sciences and Humanities, of the Heidelberg Academy for Sciences and Humanities, and of the Göttingen Academy of Sciences.
Personality
Of a genial disposition and always ready to assist, Quincke was very popular.