Die Akustik.

Leipzig:: Breitkopf & Hartel, 1802., 1802. Square 4to. (233 x 210 mm) xxxii, 310 pp. Engraved portrait vignette of the author, by F.W. Bollinger, on title-page, plus 11 engraved plates*. Modern half tan calf over marbled boards, raised bands, gilt-stamped green morocco spine label. Exlib ink stamps, bookplate of Andras Gedeon. Fine. FIRST EDITION. "Chladni, professor of physics in Breslau, was the first to reduce the general association between vibration and pitch to a tabular basis and thus to lay the foundation of the modern science of acoustics. His first results were reported in New Discoveries in the Theory of Sound (1787), and were greatly enlarged in Acoustics (1802). [Printing and the Mind of Man]. / "By spreading sand over plates and running a violin low over their edges, Chladni was able to observe the structure of the resulting vibrations, because the sand collected along the nodal curves where there was no motion. Patterns formed in this way were symmetrical and often spectacular, the lines of sand forming circles, stars, and other geometric patterns. Chladni first used circular and rectangular plates of glass and copper, three to six inches in diameter. Later he extended his observations to ellipses, semicircles, triangles, and six-sided polygons. He generally fixed the plates at one internal point, which became a node, and left the sides free." [DSB]. / In work not related to acoustics, Chladni was the first to propose that meteorites are extra-terrestrial in origin. "Contemporary scholars viewed the idea of rocks from the sky as vulgar superstition. But Chladni selected the 18 most detailed fireball reports from those dating between 1676 and 1783 and compared their apparent beginning and end points, magnitudes, velocities, and the number and force of their explosions. His results were so consistent, and the eyewitness testimony so convincing to his lawyer's ear, that Chladni concluded that solid bodies falling from fireballs are authentic natural phenomena." [Hockey]. / In 1817 a continuation of this treatise was issued Neue Beytr ge zur Akustik (xii, 90) pp. and is not included here; they are rarely seen together.* The title-page engraving of the author is counted as one of the twelve engravings as indicated on the title-page. REFERENCES: Dibner, Heralds of science 150 (1787 ed.); DSB Vol. III, pp. 258-9; Hockey, Biographical Encyclopedia of Astronomers, Vol. I, pp. 229-31; Norman 481; Poggendorff I, 430; Printing and the Mind of Man 233(b); Roberts & Trent p. 70; Sparrow, Milestones of science 38.