Ernst Chladni

Ernst Florens Friedrich Chladni (UKˈklædni, USˈklɑːdni, ɛʁnst ˈfloːʁɛns ˈfʁiːdʁɪç ˈkladniː; 30 November 1756 – 3 April 1827) was a German physicist and musician. His most important work, for which he is sometimes labeled as the father of acoustics, included research on vibrating plates and the calculation of the speed of sound for different gases. He also undertook pioneering work in the study of meteorites and is regarded by some as the father of meteoritics. Although Chladni was born in Wittenberg in Saxony, his family originated from Kremnica, then part of the Kingdom of Hungary and today a mining town in central Slovakia. Chladni has therefore been identified as German, Hungarian and Slovak. Chladni came from an educated family of academics and learned men. Chladni's great-grandfather, the Lutheran clergyman Georg Chladni (1637–1692), had left Kremnica in 1673 during the Counter Reformation. Chladni's grandfather, Martin Chladni (1669–1725), was also a Lutheran theologian and, in 1710, became professor of theology at the University of Wittenberg. He was dean of the theology faculty in 1720–1721 and later became the university's rector. Chladni's uncle, Justus Georg Chladni (1701–1765), was a law professor at the university. Another uncle, Johann Martin Chladni (1710–1759), was a theologian, a historian and a professor at the University of Erlangen and the University of Leipzig. Chladni's father, Ernst Martin Chladni (1715–1782), was a law professor and rector of the University of Wittenberg. He had joined the law faculty there in 1746. Chladni's mother was Johanna Sophia and he was an only child. His father disapproved of his son's interest in science and insisted that Chladni become a lawyer. 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. He gave lectures on law, mathematics, and natural sciences at the University of Wittenberg from 1783 to 1792.