Johann Friedrich Wilhelm von Bezold (June 21, 1837 – February 17, 1907) was a German

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate caus ...

and

meteorologist A meteorologist is a scientist who studies and works in the field of meteorology aiming to understand or predict Earth's atmospheric phenomena including the weather. Those who study meteorological phenomena are meteorologists in research, while t ...

born in

Munich Munich ( ; german: München ; bar, Minga ) is the capital and most populous city of the States of Germany, German state of Bavaria. With a population of 1,558,395 inhabitants as of 31 July 2020, it is the List of cities in Germany by popu ...

Kingdom of Bavaria The Kingdom of Bavaria (german: Königreich Bayern; ; spelled ''Baiern'' until 1825) was a German state that succeeded the former Electorate of Bavaria in 1805 and continued to exist until 1918. With the unification of Germany into the German E ...

. He is best known for discovering the

Bezold effect The Bezold effect is an optical illusion, named after a German professor of meteorology Wilhelm von Bezold (1837–1907), who discovered that a color may appear different depending on its relation to adjacent colors. It happens when small areas o ...

and the

Bezold–Brücke shift The Bezold–Brücke shift or luminance-on-hue effect is a change in hue perception as light intensity changes. As intensity increases, spectral colors shift more towards blue (if below 500 nm) or yellow (if above 500 nm). At lower inten ...

. Bezold studied mathematics and physics at the

University of Munich The Ludwig Maximilian University of Munich (simply University of Munich or LMU; german: Ludwig-Maximilians-Universität München) is a public research university in Munich, Germany. It is Germany's List of universities in Germany, sixth-oldest u ...

and the

University of Göttingen The University of Göttingen, officially the Georg August University of Göttingen, (german: Georg-August-Universität Göttingen, known informally as Georgia Augusta) is a public research university in the city of Göttingen, Germany. Founded ...

. He taught meteorology in Munich from 1861, becoming a professor in 1866. In 1868 he began teaching at the

Technical University of Munich The Technical University of Munich (TUM or TU Munich; german: Technische Universität München) is a public research university in Munich, Germany. It specializes in engineering, technology, medicine, and applied and natural sciences. Establis ...

. In 1875, he was named a member of the

Bavarian Academy of Sciences The Bavarian Academy of Sciences and Humanities (german: Bayerische Akademie der Wissenschaften) is an independent public institution, located in Munich. It appoints scholars whose research has contributed considerably to the increase of knowledg ...

. From 1885 to 1907 director of the

Prussia Prussia, , Old Prussian: ''Prūsa'' or ''Prūsija'' was a German state on the southeast coast of the Baltic Sea. It formed the German Empire under Prussian rule when it united the German states in 1871. It was ''de facto'' dissolved by an em ...

n Institute of Meteorology at the

University of Berlin Humboldt-Universität zu Berlin (german: Humboldt-Universität zu Berlin, abbreviated HU Berlin) is a German public research university in the central borough of Mitte in Berlin. It was established by Frederick William III on the initiative o ...

. As a scientist, he was mainly interested in the physics of the atmosphere, and he contributed much to the theory of

electrical storm A thunderstorm, also known as an electrical storm or a lightning storm, is a storm characterized by the presence of lightning and its acoustic effect on the Earth's atmosphere, known as thunder. Relatively weak thunderstorms are someti ...

s. Bezold was one of the early researchers of

atmospheric thermodynamics Atmospheric thermodynamics is the study of heat-to-work transformations (and their reverse) that take place in the earth's atmosphere and manifest as weather or climate. Atmospheric thermodynamics use the laws of classical thermodynamics, to descr ...

. He considered pseudo-adiabatic processes describing

air The atmosphere of Earth is the layer of gases, known collectively as air, retained by Earth's gravity that surrounds the planet and forms its planetary atmosphere. The atmosphere of Earth protects life on Earth by creating pressure allowing f ...

as it is lifted, expands, cools, and eventually condenses and precipitates its

water vapor (99.9839 °C) , - , Boiling point , , - , specific gas constant , 461.5 J/( kg·K) , - , Heat of vaporization , 2.27 MJ/kg , - , Heat capacity , 1.864 kJ/(kg·K) Water vapor, water vapour or aqueous vapor is the gaseous pha ...

. It was Bezold's investigations of Lichtenberg dust figures that were useful to

Heinrich Rudolf Hertz Heinrich Rudolf Hertz ( ; ; 22 February 1857 – 1 January 1894) was a German physicist who first conclusively proved the existence of the electromagnetic waves predicted by James Clerk Maxwell's equations of electromagnetism. The unit o ...

during his attempt to physically validate Maxwell's mathematical analysis of electromagnetic waves.Heinrich Hert
"Electric waves: being researches on the propagation of electric action with finite velocity through space"
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References

*W. von Bezold, Zur Thermodynamik der Atmosphäre. Pts. I, II. Sitz. K. Preuss. Akad. Wissensch. Berlin, pp. 485–522, 1189-1206; Gesammelte Abhandlugen, pp. 91–144. English translation by Abbe, C. The mechanics of the Earth's atmosphere. Smithsonian Miscellaneous Collections, no 843, 1893, 212-242.

External links

Wilhelm von Bezold (1876
''The theory of color and its relation to art and art-industry... translated from the German by S. R. Koehler''
- digital facsimile from the

Linda Hall Library The Linda Hall Library is a privately endowed American library of science, engineering and technology located in Kansas City, Missouri, sitting "majestically on a urban arboretum." It is the "largest independently funded public library of scien ...

1837 births 1907 deaths German meteorologists German untitled nobility 19th-century German physicists Scientists from Munich People from the Kingdom of Bavaria Ludwig Maximilian University of Munich alumni Ludwig Maximilian University of Munich faculty University of Göttingen alumni Technical University of Munich faculty Humboldt University of Berlin faculty Members of the Göttingen Academy of Sciences and Humanities {{Germany-scientist-stub