Ernst Chladni

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Ernst Chladni
Ernst Chladni
Born30 November 1756 (1756-11-30)
Died3 April 1827 (1827-04-04) (aged 70)
Known for
Scientific career

Ernst Florens Friedrich Chladni (German: [ˈɛʁnst ˈfloːʁɛns ˈfʁiːdʁɪç ˈkladnɪ]; 30 November 1756 – 3 April 1827) was a German physicist and musician. His most important work, for which he is sometimes labeled the father of acoustics, included research on vibrating plates and the calculation of the speed of sound for different gases.[1] He also undertook pioneering work in the study of meteorites and is regarded by some as the father of meteoritics.[2]

Early life[edit]


Martin Chladni, Ernst Chladni's grandfather


Chladni's method of creating Chladni figures



Chladni studied law and philosophy in Wittenberg and Leipzig, obtaining a law degree from the University of Leipzig in 1782. That same year, his father died and he turned to physics in earnest.[8][9] He gave lectures on law, mathematics, and natural sciences at the University of Wittenberg from 1783 to 1792. During this time, he began his first experiments with acoustics.[6]

Chladni figures[edit]

Chladni patterns of a guitar backplate
Chladni figure on a rectangular plate supported in center
Another mode of the same plate

One of Chladni's best-known achievements was inventing a technique to show the various modes of vibration on a rigid surface, known as Chladni figures due to the various shapes or patterns created by various modes. When resonating, a plate or membrane is divided into regions that vibrate in opposite directions, bounded by lines where no vibration occurs (nodal lines). Chladni repeated the pioneering experiments of Robert Hooke who, on July 8, 1680, had observed the nodal patterns associated with the vibrations of glass plates. Hooke ran a violin bow along the edge of a plate covered with flour and saw the nodal patterns emerge.[10][8][9][11]


Chladni had visited the Paris Academy in 1808 and had demonstrated the vibration patterns before an audience that included not only the leading French scientists but Napoleon himself, Napoleon set a prize for the best mathematical explanation. Sophie Germain's answer, although rejected due to flaws, was the only entry with the correct approach.[13]


In quantum mechanics, Chladni figures ("nodal patterns") are known to be related to the solutions of the Schrödinger equation for one-electron atoms, and the mathematics describing them was used by Erwin Schrödinger to arrive at the understanding of electron orbitals.[14]

Chladni figures
Chladni plate 24.jpg Chladni plate 23.jpg Chladni plate 16.jpg Chladni plate 25.jpg
Chladni plate 05.jpg Chladni plate 04.jpg Chladni plate 03.jpg Chladni plate 21.jpg
Chladni plate 12.jpg Chladni plate 15.jpg Chladni plate 14.jpg Chladni plate 11.jpg
Chladni plate 19.jpg Chladni plate 17.jpg Chladni plate 18.jpg Chladni plate 02.jpg
Chladni plate 22.jpg Chladni plate 26.jpg Chladni plate 27.jpg Chladni plate 20.jpg
Chladni plate 06.jpg Chladni plate 09.jpg Chladni plate 07.jpg Chladni plate 08.jpg

Musical instruments[edit]

Since at least 1738, a musical instrument called a Glasspiel or verrillon, created by filling beer glasses with varying amounts of water, was popular in Europe.[15] The beer glasses were struck by wooden mallets shaped like spoons to produce "church and other solemn music".[16] Benjamin Franklin was sufficiently impressed by a verrillon performance on a visit to London in 1757 that he created his own instrument, the glass armonica, in 1762. Franklin's armonica inspired several other instruments, including two created by Chladni. In 1791, Chladni invented the musical instrument called the euphon (not to be confused with the brass instrument euphonium), consisting of glass rods of different pitches. Chladni's euphon is the direct ancestor of the modern day musical instrument known as the Cristal Baschet.[17] Chladni also improved on Hooke's "musical cylinder" to produce another instrument, the clavicylinder, in 1799.[8][9][16]


Bowed plaque instruments - Chladni

Contributions to Meteoritics[edit]

Chladni became interested in meteoritics following a conversation he had with Georg Christoph Lichtenberg about a fireball that he supposedly saw in the Gӧttingen sky in November 1791. Inspired by this report, Chladni researched reports of similar phenomena as well as reports of other falling masses across Europe and North America within the last century. Based on the uniformity among these sightings, he concluded that the phenomena of fireballs and falling masses must be genuine.[18]

This led him to publish Über den Ursprung der von Pallas gefundenen und anderer ihr ähnlicher Eisenmassen und über einige damit in Verbindung stehende Naturerscheinungen ("On the Origin of the Iron Masses Found by Pallas and Others Similar to it, and on Some Associated Natural Phenomena") in 1794. In this book he proposed that meteorites have an extraterrestrial origin.[19][20] He argued that this would explain the high speeds of the falling masses as well as linking the masses to the fireballs; they glow intensely bright as they enter the Earth's atmosphere. He hypothesized that these meteorites were chunks of material that had either never been consolidated in the formation of larger masses or were debris from the formation and destruction of planets.[18] This was a controversial statement at the time,[21] since meteorites were thought to be of volcanic origin. Additionally, his claims challenged the established belief that nothing existed beyond the moon except for other stars and planets. Indeed, this supposed emptiness of space had fascinated Chladni as a child when he learned about the relatively large distance between Mars and Jupiter, where the Asteroid Belt is now known to exist. This observation factored into his account for the origins of meteorites.[18]

Chladni's book was initially ridiculed by contemporary physicists, including Lichtenberg.[22] Still, his writings sparked a curiosity that eventually led to more researchers supporting his theory. In 1795, a large stony meteorite was observed during its fall to Earth at a cottage near Wold Newton in Yorkshire, England and a piece of it, known as the Wold Cottage meteorite, was given to the British chemist Edward Howard who, along with French mineralogist Jacques de Bournon, carefully analyzed its composition and concluded that an extraterrestrial origin was likely, noting that the sample bore a strong resemblance to a sample of a meteorite from an early meteor shower in Siena, Italy.[23] Although that event had been attributed to an eruption of Mount Vesuvius, no similar volcanoes existed within the same range of Wold Netwon, with the closest being in Hekla.[22][23] In 1803, the physicist and astronomer Jean Baptiste Biot was commissioned by the French Minister of the Interior to investigate a meteor shower over L'Aigle in northern France that had peppered the town with thousands of meteorite fragments.[24][8][9] Unlike Chladni's book and the scientific publication by Howard and de Bournon, Biot's lively report became popular and persuaded more people to take Chladni's insights seriously.[20]

Chladni's insights have led some in the field to call him the "father of meteoritics" while others have been more conservative with their appraisal of Chladni's contributions to the field.[18]

Chladni continued to develop his record of meteorite sightings throughout the next several decades as well as amassing a collection of meteorite samples. He donated this collection to the Mineralogical Museum of Berlin University in 1827 and it now resides in the Museum of Natural History at Humboldt University of Berlin.[25][26]

A mineral, first described in 1993 from the Carlton (IIICD) iron meteorite, was named chladniite in his honor.[2][27]

Other work[edit]

Chladni discovered Chladni's law, a simple algebraic relation for approximating the modal frequencies of the free oscillations of plates and other bodies.[28]

Chladni estimated sound velocities in different gases by placing those gases in an organ pipe and measuring the characteristics of the sounds that emerged when the pipe was played.[29] This built on work on measuring the speed of sound in air that Pierre Gassendi began in 1635.[citation needed]


Chladni died on April 3, 1827, in Breslau, Lower Silesia, then part of the Kingdom of Prussia and today the city of Wrocław in southwestern Poland.[30]


  • Entdeckungen über die Theorie des Klanges, Leipzig 1787.
  • Beiträge zur praktischen Akustik und zur Lehre vom Instrumentbau, Leipzig 1821 (OCLC 457664981).
  • Über den Ursprung der von Pallas gefundenen und anderer ihr ähnlicher Eisenmassen at the HathiTrust Digital Library, Leipzig/Riga 1794.
  • Über Feuermeteore, Vienna 1820.
  • Über die Hervorbringung der menschlichen Sprachlaute, Leipzig 1824.

See also[edit]


  2. ^ a b McCoy, T. J.; Steele, I. M.; Keil, K.; Leonard, B. F.; Endress, M.; Steele; Keil; Leonard; Endress (1993). "Chladniite: A New Mineral Honoring the Father of Meteoritics". Meteoritics. 28 (3): 394. Bibcode:1993Metic..28Q.394M.CS1 maint: multiple names: authors list (link)
  3. ^ "Ernst Florens Friedrich Chladni, or Ernst F. F. Chladni (German physicist)", Encyclopædia Britannica: Related Articles
  5. ^ McLaughlin, Joyce (1998). "Good Vibrations". American Scientist. 86 (4): 342. Bibcode:1998AmSci..86..342M. doi:10.1511/1998.4.342. Archived from the original on 2008-01-23. Retrieved 2007-11-02.
  6. ^ a b c d "Life and work of E.F.F. Chladni", D. Ullmann1, The European Physical Journal – Special Topics, Springer, Berlin / Heidelberg, ISSN 1951-6355 (Print) ISSN 1951-6401 (Online), Issue Volume 145, Number 1, June 2007, doi:10.1140/epjst/e2007-00145-4, pp. 25–32
  8. ^ a b c d e Daniel P McVeigh (2000). "Ernst Florens Friedrich Chladni". An Early History of the Telephone 1664-1865. Archived from the original on 2013-03-07.
  10. ^ Hooke, Robert (1935). Robinson, Henry W.; Adams, Walter (eds.). The Diary of Robert Hooke, M.A., M.D., F.R.S., 1672–1680 …. London, England: Taylor & Francis. p. 448.
  11. ^ Galileo had observed vibrational patterns in a brass plate as early as 1638. See: Galilei, Galileo; Crew, Henry and de Salvio, Alfonso, trans. (first published in Italian 1638; 1914) Dialogues Concerning Two New Sciences New York City, New York, USA: Macmillan Co. pp. 101–102. From p. 100: "As I was scraping a brass plate with a sharp iron chisel in order to remove some spots from it and was running the chisel rather rapidly over it, I once or twice, during many strokes, heard the plate emit a rather strong and clear whistling sound; on looking at the plate more carefully, I noticed a long row of fine streaks parallel and equidistant from one another."
  13. ^ "Revolutionary Mathematician". San Diego Supercomputer Center. Retrieved 16 March 2016.
  14. ^ J. Michael McBride, "Chladni Figures and One-Electron Atoms", Lecture #9, Freshman Organic Chemistry (CHEM 125) course, Open Yale Courses, Yale University, video recorded Fall 2008, accessed on YouTube,, 2016-06-05.
  15. ^ Schlesinger, Kathleen (1911). "Harmonica" . Encyclopædia Britannica. 12 (11th ed.). p. 956. The 1911 edition of the Encyclopædia Britannica also credits Edward Delaval with inventing the verrillon.
  16. ^ a b Schlesinger, Kathleen (1911). "Harmonica" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. 12 (11th ed.). Cambridge University Press. p. 956.
  17. ^ "Les Sculptures Sonores: The Sound Sculptures of Bernard and Francois Baschet" by Francois Baschet, Author(s) of Review: Rahma Khazam, Leonardo, Vol. 33, No. 4 (2000), pp. 336–337
  18. ^ a b c d Marvin, Ursula B. (1996). "Ernst Florens Friedrich Chladni (1756–1827) and the origins of modern meteorite research". Meteoritics & Planetary Science. 31 (5): 545–588. doi:10.1111/j.1945-5100.1996.tb02031.x. ISSN 1945-5100.
  19. ^ Chladni, Ernst Florens Friedrich, Über den Ursprung der von Pallas gefundenen und anderer ihr ähnlicher Eisenmassen und über einige damit in Verbindung stehende Naturerscheinungen [On the origin of the iron masses found by Pallas and others similar to it, and on some natural phenomena associated with them] (Riga, Latvia: Johann Friedrich Hartknoch, 1794). Available on-line at: Saxon State and University Library at Dresden, Germany.
  20. ^ a b McSween, Harry Y. (1999). Meteorites and Their Parent Planets (2. ed.). Cambridge [u.a.]: Cambridge University Press. ISBN 978-0-521-58303-9.
  21. ^ Williams, Henry Smith (1904). "5". A History of Science. 3. Harper. p. 168ff. ISBN 978-0-250-40142-0.
  22. ^ a b Ron Cowen. “After the Fall.” Science News, vol. 148, no. 16, 1995, pp. 248–249. JSTOR, Accessed 16 Mar. 2020.
  23. ^ a b Howard, Edward (1802). "Experiments and observations on certain stony and metalline substances, which at different times are said to have fallen on the Earth; also on various kinds of native iron". Philosophical Transactions of the Royal Society of London. 92: 168–212. Bibcode:1802RSPT...92..168H. doi:10.1098/rstl.1802.0009.
  24. ^ See:
    • Biot, J.-B. (1803). "Relation d'un voyage fait dans le département de l'Orne pour constater la réalité d'un météore observé à l'Aigle le 6 floréal an XI" [Account of a trip made in the department of Orne to note the reality of a meteor observed at l'Aigle on 6 Floréal year XI]. Mémoires de la Classe des Sciences Mathématiques et Physiques de l'Institut National de France (in French). 7: 224–265.
    • Reprinted as a pamphlet: Biot, J.-B. (1803). Relation d'un voyage fait dans le département de l'Orne pour constater la réalité d'un météore observé à l'Aigle le 6 floréal an XI [Account of a trip made in the department of Orne to note the reality of a meteor observed at l'Aigle on 6 Floréal year XI] (in French). Paris, France: Baudoin.
  25. ^ Chladni, E. F. F. (2009-08-10). "I. A new catalogue of meteoric stones, masses of meteoric iron, and other substances, the fall of which has been made known, down to the present time". The Philosophical Magazine. doi:10.1080/14786442608674005.
  26. ^ Knöfel, A., and J. Rendtel. "Chladni and the cosmic origin of fireballs and meteorites. Two hundred years of meteor astronomy and meteorite science." WGN, Journal of the International Meteor Organization 22 (1994): 217-219.
  27. ^ McCoy, T.J.; Steele, I.M.; Keil, K.; Leonard, B.F.; Endreβ, M. (1994). "Chladniite, Na2CaMg7(PO4)6: A new mineral from the Carlton (IIICD) iron meteorite". American Mineralogist. 79: 375–380. Bibcode:1994AmMin..79..375M.
  28. ^ Kverno, Derek; Nolen, Jim. "History of Chladni's Law". Davidson College Physics Department. Retrieved 2018-04-02.
  30. ^ Musielak, Dora E. (23 January 2015). Prime Mystery: The Life and Mathematics of Sophie Germain. AuthorHouse. p. 52. ISBN 9781496965011. Retrieved 1 April 2018.

Further reading[edit]

  • Marvin, Ursula B. (1996). "Ernst florens Friedrich Chladni (1756–1827) and the origins of modern meteorite research". Meteoritics. 31 (5): 545–588. Bibcode:1996M&PS...31..545M. doi:10.1111/j.1945-5100.1996.tb02031.x.

External links[edit]