412 



KIRCHHOFF, GUSTAV EGBERT. 



of 34,839. The successful candidates assumed 

 their offices on August 30. 



The people also voted at the same election, 

 in accordance with an act of the last Legisla- 

 ture, on the question whether a convention 

 should be called to prepare a new Constitution 

 for the State. The vote from all but 11 coun- 

 ties was 162,557 in favor and 49,795 against ; 

 number not voting, 65,956. Should the next 

 Legislature order a similar vote in 1889, and the 

 result be again favorable to a convention, it 

 may then be called to meet in 1890. 



KIRCHHOFF, GIJSTAV ROBERT, a German phy- 

 sicist, born in Konigsberg, Prussia, March 12, 

 1824; died in Berlin, Oct. 17, 1887. He was 

 graduated at the university of his native city 

 in 1846, where he gave special attention to 

 mathematics and physics. In 1847 he went to 

 Berlin, and a. year later began his career at the 

 university as a lecturer on mathematical phys- 

 ics. He was called in 1850 to be Assistant Pro- 

 fessor of Experimental Physics at the University 

 of Breslau, and in 1850 accepted the chair of 

 Physics at Heidelberg, passing thence in 1874 



GUSTAV ROBERT KIRCHHOFF. 



to a similar appointment in the University of 

 Berlin, where he remained until his death. 

 His scientific work began in 1845, a year before 

 he received his degree by the publication of a 

 paper in Poggendorff s " Annalen " " On Elec- 

 tric Conduction in a Thin Plate, and especially 

 in a Circular One," soon followed by other re- 

 searches on electric questions, among which are 

 those on conduction in curved sheets, on Ohm's 

 law, on the distribution of electricity on two 

 influencing spheres, on the discharge of the 

 Leyden-jar, on the motion of electricity, on the 

 determination of the constants on which de- 

 pends the intensity of induced currents, and 

 two important papers on induced magnetism. 

 Another series of investigations dealt with the 

 equilibrium and motion of elastic solids, espe- 

 cially in the forms of plates and solids, including 

 also careful experimental determinations of the 

 value of Poisson's ratio for different substances. 



Besides these papers he published several note- 

 worthy memoirs on important propositions in 

 the thermo-dynamics of solution and vaporiza- 

 tion, on crystalline reflection and refraction, 

 on the influence of heat in a special case of 

 propagation of sound, on the optical constants 

 of aragonite, and on the thermal conductivity 

 of wire. In 1859 he made his discovery of the 

 cause of Fraunhofer's lines in the solar spec- 

 trum, and was the first to announce and prove 

 the now-accepted law that "the relation be- 

 tween the power of emission and the power of 

 absorption of one and the same class of rays is 

 the same for all bodies at the same tempera- 

 ture." He associated with himself Robert W. 

 Bunsen, and together they evolved the method 

 of spectrum analysis, and in 1860 perfected it 

 in its essentials. It was at once recognized as 

 a classical discovery, and its great value as an 

 analytical method of investigation in terrestrial 

 and celestial chemistry can not be overestimated. 

 The history of spectrum analysis has from that 

 date been one of unbroken progress. In as- 

 tronomy the constitution of the heavenly 

 bodies and their motions directly toward or 

 away from the observer, have all been investi- 

 gated or determined by this method. The atmos- 

 phere of a star, comet, or nebula yields its com- 

 position to the analyst, who can also approxi- 

 mately determine the temperature and pressure 

 of the glowing gas. In chemistry, new metals 

 have been found by its means. Cassium and 

 rubidium by Bunsen, thallium by Crookes, gal- 

 lium by Lecoq de Boisbaudran, and scandium by 

 Nilsen. Were it only for its part in completing 

 the relation of the atomic weights of the ele- 

 ments by Mendelejeff 's law, the indebtedness 

 of chemistry to it would be great. His latest 

 work was in electricity, and in 1884'85 he pub- 

 lished papers on the changes and distribution 

 of electricity in certain bodies which he exam- 

 ined for this purpose. Prof. Kirchhoff became 

 in 1870 a member of the Berlin Academy of 

 Sciences, and was an honorary or correspond- 

 ing member of the leading scientific societies 

 of the world, including his relation as one of 

 the very few foreign associates of the National 

 Academy of Sciences in the United States. His 

 own Government honored him with the title of 

 "geheimrath," or privy councilor, and con- 

 ferred on him the Prussian order " Pour la me- 

 rite" the highest honor awarded in Germany. 

 His collected papers were published as "Ge- 

 sammelte Abhandlungen, von G. Kirchhoff" 

 (Leipsic, 1882). His other works are " Unter- 

 suchungen iiber das Sonnenspectrnm und die 

 Spectren des chemischen Elemente" (Berlin, 

 1861), translated as "Studies of the Solar Spec- 

 trum and the Spectra of Simple Bodies " (Lon- 

 don, 1862) ; with Bunsen, " Chemische Analyse 

 durch Spectralbeobaohtung " (Vienna, 1861); 

 and his lectures on dynamics, " Vorlesungen 

 iiber analytische Mechanik, mit Einschluss der 

 Hydrodynamik und der Theorie der Elasti- 

 citat fester Korper " (Leipsic, 1874). 



