Ernst Florens Friedrich Chladni, a German physicist, born in Wittenberg, Nov. 30, 1756, died in Breslau, April 4, 1827. Educated for the profession of law, he early left its practice and gave himself to the science of acoustics. He was especially successful in experimenting upon the velocity of sound in various bodies, gaseous and solid; and even more so in experiments and calculations on the movements of plates of glass when in acoustic vibration, He also distinguished himself by being the first scientific man who defended the popular opinion of the fall of solid bodies from the sky. Chladni was the inventor of the musical instruments called the euphonon and the clavicylinder. His principal works are: Entdechungen uber die Theorie des Klanges (Leipsic, 1787); Die Akustik (Leipsic 1802; translated into French, Traite d'acovstique, Paris, 1809); Ueber Feuermeteore (Vienna, 1819); Neue Beitrdge zur Akustik (Leipsic, 1817); and Beitrdge zur Akustik und zur Lehre torn Instrumentaloau (Leipsic, 1822). (See Acoustics.)