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GAYARRE, CHARLES ETIENNE ARTHUR (1805...
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See also:GAYARRE, See also: Three years later he was transferred to the Ecole See also:des Ponta et Chaussees, and shortly afterwards was assigned to C. L. Berthollet, who wanted an able student to help in his researches. The new assistant scarcely came up to expectations in respect of confirming certain theoretical views of his See also:master's by the experiments set him to that end, and appears to have stated the discrepancy without reserve; but Berthollet nevertheless quickly recognized the ability displayed, and showed his appreciation not only by desiring to be Gay-Lussac's " See also:father in See also:science," but also by making him in 18o7 an See also:original member of the Societe d'See also:Arcueil. In 1802 he was appointed demonstrator to A. F. See also:Fourcroy at the Ecole Poly-technique, where subsequently (1809) he became See also:professor of See also:chemistry, and from 18o8 to 1832 he was professor of physics at the See also:Sorbonne, a See also:post which he only resigned for the See also:chair of chemistry at the Jardin des Plantes. In 1831 he was elected to represent Haute Vienne in the chamber of deputies, and in 1839 he entered the chamber of peers. He died in Paris on the 9th of May 185o. Gay-Lussac's earlier researches were mostly See also:physical in See also:character and referred mainly to the properties of gases, vapour-tensions, hygrometry, capillarity, &c. In his first memoir (See also:Ann. de Chimie, 1802) he showed that different gases are dilated in the same proportion when heated from o° to 100° C. Apparently he did not know of See also:Dalton's experiments on the same point, which indeed were far from accurate; but in a See also:note he explained that " le cit. Charles avait remarque depuis 15 ans la meme propriete clans See also:ces gaz; mais n'ayant jamais publie ses resultats, c'est See also:par le plus See also:grand hasard que je See also:les ai connus." In See also:con-sequence of his candour in thus rescuing from oblivion the observation which his See also:fellow-See also:citizen did not think See also:worth See also:publishing, his name is sometimes dissociated from this law, which instead is known as that of Charles. In 1804 he had an opportunity of prosecuting his researches on See also:air in somewhat unusual conditions, for the French See also:Academy, desirous of securing some observations on the force of terrestrial See also:magnetism at See also:great elevations above the See also:earth, through Berthollet and J. E. See also:Chaptal obtained the use of the See also:balloon which had been employed in See also:Egypt, and entrusted the task to him and J. B. See also:Biot. In their first ascent from the See also:garden of the See also:Conservatoire des Arts on the 24th of See also:August 1804 an See also:altitude of 4000 metres (about 13,000 ft.) was attained. But this See also:elevation was not considered sufficient by Gay-Lussac, who therefore made a second ascent by himself on the 16th of See also:September, when the balloon See also:rose 7016 metres (about 23,000 ft.) above See also:sea-level. At this height, with the thermometer marking 92 degrees below freezing, he remained for a considerable See also:time, making observations not only on magnetism, but also on the temperature and humidity of the air, and See also:collecting several samples of air at different heights. The magnetic observations, though imperfect, led him to the conclusion that the magnetic effect at all attainable elevations above
the earth's See also:surface remains See also:constant; and on analysing the samples of air he could find no difference of See also:composition at different heights. (For an account of both ascents see Journ. de phys. for 1804.) On the 1st of See also:October in the same See also:year, in See also:conjunction with See also: This journey was interrupted in the See also:spring of 18o6 by the See also:news of the See also:death of M. J. See also:Brisson, and Gay-Lussac hurried back to Paris in the See also:hope, which was gratified, that he would be elected to the seat thus vacated in the Academy. In 1809 an account of the magnetic observations made during the tour with Humboldt was published in the first volume of the Memoires d'Arcueil, and the second volume, published in 1809, contained the important memoir on gaseous combination (read to the Societe Philomathique on the last See also:day of 18o8), in which he pointed out that gases combining with each other in volume do so in the simplest proportions—1 to 1, 1 to 2, r to 3—and that the. volume of the See also:compound formed bears a See also:simple ratio to that of the constituents. About this time Gay-Lussac's See also:work, although he by no means entirely abandoned physical questions, became of a more chemical character; and in three instances it brought him into See also:direct rivalry with See also:Sir See also:Humphry See also:Davy. In the first See also:case Davy's preparation of See also:potassium and See also:sodium by the electric current spurred on Gay-Lussac and his collaborator L. J. See also:Thenard, who had no See also:battery at their disposal, to See also:search for a chemical method of obtaining those metals, and by the See also:action of red-hot See also:iron on fused potash—a method of which Davy admitted the advantages —they succeeded in 18o8 in preparing potassium, going on to make a full study of its properties and to use it, as Davy also did, for the reduction of See also:boron from boracic See also:acid in 1809. The second concerned the nature of " oxymuriatic acid " (See also:chlorine). While admitting the possibility that it was an elementary See also:body, after many experiments they finally declared it to be a compound (Hem. d'Arcueil, 1809). Davy, on the other See also:hand, could see no See also:reason to suppose it contained oxygen, as they surmised, and ultimately they had to accept his view of its elementary character. The third case roused most feeling of all. Davy, passing through Paris on his way to Italy at the end of 1813, obtained a few fragments of See also:iodine, which had been discovered by See also:Bernard See also:Courtois (1777-1838) in 1811, and after a brief examination by the aid of his limited portable laboratory perceived its See also:analogy to chlorine and inferred it to be an See also:element. Gay-Lussac, it is said, was nettled at the See also:idea of a foreigner making such a discovery in Paris, and vigorously took up the study of the new substance, the result being the elaborate " Memoire sur 1'iode," which appeared in the Ann. de chim. in 1814. He too saw its resemblance to chlorine, and was obliged to agree with Davy's See also:opinion as to its simple nature, though not without some hesitation, due doubtless to his previous See also:declaration about chlorine. Davy on his See also:side seems to have See also:felt that the French chemist was competing with him, not altogether fairly, in trying to appropriate the See also:honour of discovering the character of the substance and of its compound, hydriodic acid. In 1810 he published a paper which contains some classic experiments on See also:fermentation, a subject to which he returned in a second paper published in 1815. At the same time he was working with Thenard at the improvement of the methods of organic analysis, and by See also:combustion with oxidizing agents,' first potassium chlorate and subsequently See also:copper See also:oxide, he determined the composition of a number of organic substances. But his last great piece of pure See also:research was on prussic acid. In a note published in x811 he described the physical properties of this acid, but he said nothing about its chemical composition till 1815, when he described See also:cyanogen as a compound radicle, prussic acid as a compound of that radicle with hydrogen alone, and the prussiates (cyanides) as compounds of the radicle with metals. The See also:proof that prussic acid contains hydrogen but no oxygen was a most important support to the hydrogen-acid theory, and completed the downfall of See also:Lavoisier's oxygen theory; while the See also:isolation of cyanogen was of equal importance for the subsequent era of compound radicles in organic chemistry. After this research Gay-Lussac's See also:attention began to be distracted from purely scientific investigation. He had now secured a leading if not the foremost See also:place among the chemists of the French See also:capital, and the demand for his services as adviser in technical problems and matters of See also:practical See also:interest made great inroads on his available time. He had been a member of the consultative See also:committee on arts and manufactures since 18o5; he was attached to the See also:administration des poudres et salpetres in 1818, and in 1829 he received the lucrative post of assayer to the See also:mint. In these new See also:fields he displayed the See also:powers so conspicuous in his scientific inquiries, and he was now to introduce and establish scientific accuracy where previously there had been merely practical approximations. His services to See also:industry included his improvements in the processes for the manufacture of sulphuric acid (1818) and oxalic acid (1829); methods of estimating the amount of real See also:alkali in potash and soda by the volume of See also:standard acid required for neutralization, and for estimating the available chlorine in See also:bleaching See also:powder by a See also:solution of arsenious acid; directions for the use of the centesimal alcoholometer published in 1824 and specially commended by the See also:Institute; and the elaboration of a method of See also:assaying See also:silver by a standard solution of See also:common See also:salt, a volume on which was published in 1833. Among his research work of this See also:period may be mentioned the improvements in organic analysis and the investigation of fulminic acid made with the help of See also:Liebig, who gained the See also:privilege of See also:admission to his private laboratory in 1823,-1824. Gay-Lussac was patient, persevering, accurate to punctiliousness, perhaps a little See also:cold and reserved, and not unaware of his great ability. But he was also bold and energetic, not only in his work but also in support and See also:defence of his See also:friends. His early childish adventures, as told by See also:Arago, See also:herald the fearless aeronaut and the undaunted investigator of volcanic eruptions (See also:Vesuvius was in full eruption when he visited it during his tour in 18os); and the endurance he exhibited under the laboratory accidents that befell him shows the See also:power of will with which he would See also:face the prospect of becoming See also:blind and useless for the See also:prosecution of the science which was his very See also:life, and of which he was one of the most distinguished ornaments. Only at the very end, when the disease from which he was suffering See also:left him no hope, did he complain with some bitterness of the hardship of leaving this See also:world where the many discoveries being made pointed to yet greater discoveries to come. The most See also:complete See also:list of Gay-Lussac's papers is contained in the Royal Society's See also:Catalogue of Scientific Papers, which enumerates 148, exclusive of others written jointly with Humboldt, Thenard, Welter and Liebig. Many of them were published in the Annales de chimie, which after it changed its See also:title to Annales de chimie et physique he edited, with Arago, up to nearly the end of his life; but some are to be found in the Memoires d'Arcueil and the Comptes rendus, and in the Recherches physiques et chimiques, published with Thenard in 1811. Additional information and CommentsThere are no comments yet for this article.
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