Beschreibung:

DOPPLER, Johann Christian (1803-1853). "Ueber das farbige Licht der Doppelsterne und einiger anderer Gestirne des Himmels". Offprint from Abhandlungen der knigl. bhmischen Gesellschaft der Wissenschaften zu Prag , 5th series, vol. 2 (1842). Prague: Gottlieb Haase for Borrosch & Andr, 1842. 4 o (254 x 209 mm). 18 pp. Lithographed plate of diagrams. (Paper restoration to lower blank corners, not affecting text.) Modern morocco-backed boards. Provenance : ALEXANDER VON HUMBOLDT (1769-1859), natural scientist and explorer (presentation inscription on title "Pour M r Arago", with two notes on suggested further reading, and a few passages marked in text), given to: DOMINIQUE FRANOIS JEAN ARAGO (1786-1853), physicist and astronomer. IMPORTANT ASSOCIATION COPY OF THE FIRST EDITION, offprint issue, containing the first statement of the Doppler principle, a fundamental tool of modern astronomy. The principle "relates the observed frequency of a wave to the motion of the source or the observer relative to the medium in which the wave is propagated" (DSB). In his paper, read to the Prague Gesellschaft fr Wissenschaft on 25 May 1842, Doppler noted the application of the principle to both acoustics and optics, specifically to the colored appearance of double stars and to the fluctuation of novae. Although Doppler, "the earliest important physicist in Austria in the nineteenth century" (ibid.), made some incorrect assumptions about the nature of stellar light, due largely to the isolation in which he worked, his theory was soon borne out through experimentation. In 1845 the acoustical effect was demonstrated by the Dutch meteorologist Christophe Buys Ballot, who used a locomotive drawing an open car containing several trumpeters. The effect was also described separately by John Scott Russell and Hippolyte Fizeau in 1848, probably without knowledge of Doppler's work. Fizeau, noting the effect's application to optics, mentioned its potential usefulness for astronomical observation. This was borne out 20 years later, when the British astrophysicist William Huggins was able to calculate the velocity of the star Sirius's movement away from the earth by measuring the shift in its spectra. "Since then the technique has provided the science of astrophysics with one of its most important tools for measuring the size and the structure of the universe" (ibid.) The provenance of this copy is particularly evocative in its association of three great 19th-century men of science. It was probably sent by Doppler directly to Alexander von Humboldt at the time residing in Paris. Although Humboldt's cherished field was geomagnetism, his interests were wide-ranging. Possessed of an unusually comprehensive view of current scientific developments, he was rather "a servant of worldwide science" (DSB) than a specialist, and his voluminous correspondence reached all corners of the globe. He was thus an appropriate recipient for a paper that had such far-reaching implications for two different branches of science. In 1845 or later Humboldt sent the offprint to his longstanding friend Franois Arago, whose interests centered on electromagnetism, optical instruments, and the nature of light, and he inscribed on it suggestions for further reading: Arago should compare Doppler's paper, he writes, to an article in vol. 16 of the Comptes rendus de l'Acadmie des Sciences , and to the report of Buys Ballot's "railroad" experiment, described in vol. 66 of the Annalen der Physik und Chemie . Norman 651.