1-5 of 5 results  for:

  • Late 18th c./Classical (1750-1800) x
Clear all

Article

C. Truesdell

revised by Clive Greated

(Florenz Friedrich)

(b Wittenberg, Nov 30, 1756; d Breslau [now Wrocław], April 3, 1827). German acoustician. He studied law at Leipzig University before turning to scientific studies. He invented two instruments, the ‘euphon’ and the ‘klavizylinder’, both of which were variants of the glass harmonica. However, he owes his fame to his celebrated experiments on the nodal patterns and corresponding frequencies of vibration plates. He showed that the vibration patterns, often called Chladni figures, could be made visible by sprinkling sand on the plate. The sand is thrown up on vibrating areas and collects around nodal lines. Chladni travelled through Europe playing on his instruments and demonstrating his experiments before many persons and institutions; he encountered Goethe, Lichtenberg, Olbers, Laplace, Napoleon and other notable men of the period. Chladni's experiments stimulated much early work on the vibration of plates and bars and indeed so impressed the Académie des Sciences, Paris, that it offered a prize for a successful explanation of his sand figures and the motion of elastic surfaces in general. His work helped to form the foundation of modern theories, capable of predicting precise vibration patterns for violin and guitar top plates and the soundboards of keyboard instruments....

Article

Clive Greated

(b Basle, April 4, 1707; d St Petersburg, Sept 18, 1783). Swiss mathematician, scientist and philosopher. He studied at Basle University under Johann Bernoulli. When he was 20, he took (at Daniel Bernoulli's suggestion) a post at the Academy of Sciences in St Petersburg; he held a post in Berlin (1741–66), then returned to St Petersburg. He won the Grand Prix of the Paris Académie des Sciences 12 times. The most prolific of scientists, he published some 800 memoirs and 50 books or pamphlets on various branches of mathematical science and some domains of engineering, music, philosophy and religion.

Euler contributed more to theoretical acoustics as the subject is now known than has any other man. At the age of 19 he wrote Dissertatio physica de sono, in which he divided sounds into three kinds (the tremblings of solid bodies; the sudden release of compressed or rarefied air; and oscillations of air, either freely or confined). Acoustics was one of his favourite subjects. His notebooks show that as a boy of 19 he planned to write a treatise on all aspects of music, including form and composition as well as acoustics and harmony. The only part of this project to come to fruition was his ...

Article

(b Turin, Jan 25, 1736; d Paris, April 10, 1813). French mathematician and physicist. He was largely self-trained and was encouraged by Euler and d'Alembert, whose protégé he became. He held positions in Berlin (from 1766) and Paris (from 1787). He is remembered as an acoustician for his work in 1759 on the transverse vibrations of the taut, massless cord loaded by n weights, equally spaced. He is credited with being the first to represent the string in this way and to calculate its normal mode patterns and frequencies, and for having established Euler's solution for the continuous monochord as being the result of taking the limit as n tends to infinity. In fact the discrete model was a very old one, and Lagrange's work on it is a straightforward extension of Euler's; further, as d'Alembert pointed out, Lagrange's passage to the limit is fallacious. In ...

Article

Murray Campbell

(b Mulhouse, ?Aug 26, 1728; d Berlin, Sept 25, 1777). German scientist. From 1748 to 1758 he was tutor to the children of a Swiss noble family; in 1765 he managed to obtain a post at the Akademie der Wissenschaften in Berlin. He was one of those universal scientists characteristic of the 17th and 18th centuries, and was a figure of particular importance in several subjects mainly connected with physics and mathematics. He determined very precisely the frequencies of the first eight overtones of a bar in its clamped-free modes, correcting and extending Euler’s results; the results of Rayleigh and others, a century or more later, were less conclusive. Lambert projected a musical instrument, the ‘musique solitaire’, whereby a person might enjoy music through his teeth without awakening sleepers.

C.J. Scriba: ‘Lambert, Johann Heinrich’, Dictionary of Scientific Biography, ed. C.C. Gillispie (New York, 1970–80) R. Jaquel: Le savant et philosophe mulhousien Jean-Henri Lambert (1728–1777): études critiques et documentaires...

Article

Mark Lindley

(b Montpellier, Sept 14, 1723; d Montpellier, Nov 8, 1766). French dilettante and scientist. In December 1751 he announced his discovery of difference tones, which he had made by experiments with wind instruments. (Nearly three years later Tartini, evidently unaware of Romieu’s work, published his discovery of the same phenomenon observed in double stops on the violin.) Romieu’s ‘Mémoire théorique & practique sur les systèmes temperés de musique’, published in the 1758 Mémoires of the Académie Royale des Sciences, surveyed various regular tuning systems and expressed preference for ⅙-comma mean-tone temperament and its theoretical equivalent, the division of the octave into 55 equal parts.

E. Roche: ‘Notice sur les travaux de J.-B. Romieu’, Mémoires de l’Académie des sciences et lettres de Montpellier, 9 (1879)J.M. Barbour: Tuning and Temperament: a Historical Survey (East Lansing, MI, 1951/R, 2/1953)P. Barbieri: ‘Il “migliore” sistema musicale temperato: querelles fra Estève, Romieu e altri accademici francesi (c.1740–60)’, ...