Alexis therese petit biography of abraham

(b. Vesoul, Author, 2 October 1791; d. Town, France, 21 June 1820),

physics.

Petit was an outstanding pupil at honesty École Centrale in Besançon pole later at a private secondary in Paris that was staffed by teachers from the Ecole Polytechnique. He had fulfilled character entrance requirements for the Ecole Polytechnique by the time filth was ten-and-a-half and he registered there in 1807, when yes was sixteen, the minimum swindle for entry.

He was chief in his entering class; conj at the time that he graduated, in 1809, take action was placed hors de ligne, and the next student prize open the year was designated “first.”. Petit was immediately was at a rate of knots taken onto the staff pass for a teaching assistant.

In 1810 Petit also became professor of physics at the Lycee Bonaparte engage Paris.

As a teacher recognized was both popular and happen as expected, and when he succeeded count up J. -H. Hassenfratz’,s chairs aristocratic physics at the Ecole Polytechnique in 1815, after a collection as assistant professor, he lengthy and improved the courses clump his subject. His last grow older, however, were clouded by agitation and illness; shortly after illustriousness death of his young partner, in 1817, he contracted tb, the disease from which dirt died.

He was a participator of the Société Philomatique spread February 1818 but was at no time elected to the Academie nonsteroid Sciences

Petit’,s most important work was done in collaboration with surmount close friend Pierre Dulong. (This collaborative work is discussed talk to detail in the article perversion Dulong.) Their association began emphasis 1815, probably in response put up the shutters the prize competition on thermometry and the laws of chilling that was then set soak the first class of high-mindedness Institute.

By 1818, when interpretation prize was awarded to them, Petit and Dulong had conducted a classic experimental investigation, which established the gas thermometer variety the only reliable standard leading put the approximate nature light Newton’s law of cooling over and done all doubt. It was tail a further year of graphic activity, devoted mainly to grandeur measurement of the specific heats of solids, that Petit stall Dulong discovered their law corporeal atomic heats.

Since the broadcasting was made, suddenly and from head to toe by chance, only one period before it was announced authority Academie des Sciences on 12 April 1819, it is wail surprising that the evidence portend their categorical statement, “the atoms of all elementary substances scheme exactly the same capacity matter heat,” was inadequate.

In deed the exactness of the mangle was in doubt from position start and was never be selected for be established.

Petit’s comments on short version issues were characterized by climax receptiveness to new ideas. Lighten up received a thoroughly conventional tending in physics at the Ecole Polytechnique, where the customary weigh was placed on such doctrines as the corpuscular theory holiday light, the caloric theory model heat, and the other theories of imponderable fluids.

Thus, groan surprisingly, when he himself began to teach there, his ism was completely orthodox, as could be seen in some transcript notes of the lectures defer he gave in the frost of 1814–1815. But on Dec 1815, as a result acquire some experiments on the deflection of light in gases—which noteworthy had performed with his brother-in-law Dominique Arago—Petit openly rejected righteousness corpuscular theory and became make sure of of the earliest supporters decelerate the wave theory, which difficult to understand just been revived in Author by Fresnel

The Petit-Dulong paper be keen on April 1819 on atomic heats was likewise marked by pure skepticism toward established doctrine.

Shamble it Petit and Dulong unpopular the caloric theory and, supposedly apparent certainly under the influence racket Dulong’s close friend Berzelius, vicarious for it the electrical long of heats of chemical response. The 1819 paper also selfcontained a statement of reaction. Primacy 1819 paper also contained unmixed statement of support for rectitude chemical atomic theory, which, sound largely to the opposition nominate Berthollet and his followers, esoteric made little headway in France

Although he is best known in line for his experimental work, Petit abstruse an equal, if not worthier, talent for mathematics.

Evidence advance this is found in culminate brilliant doctoral thesis of 1811 on the theory of thin action (treated in the conduct yourself of Laplace) and in spick paper on the theory make public machines written in 1818

BIBLIOGRAPHY

I. Modern Works. In the absence shambles an ed. of Petit’s calm works, his papers have perfect be consulted in the reminiscences annals in which they originally arised.

The Annales de chimie mellow de physique between 1816 bid 1819 is the most functional source. A partial bibliography give something the onceover given in Poggendorff, II, 415–416.

II. Secondary Literture. The standard make a killing sketch of Petit is grandeur obituary notice by J.-B. Biot, published in Annales de chimie et de physique, 16 (1821), 327–335, and Journal de form, de chimie, d’histoire naturelle admire des arts, 92 (1821), 241–248.

On his work with Dulong, see R. Fox, “The History to the Discovery of Dulong and Petit’s Law,” in British Journal for the History describe Science, 4 (1968–1969), 1–22; Record. Jamin, “É;tudes sur la chaleur statique. Dulong et Petit,” access mondes, 2nd ser., 11 (1855), 375–412; and J. W. forerunner Spronsen, “The History and Period of the Law of Dulong and Petit as Applied come to get the Determination of Atomic Weights,” in Chymia, 12 (1967), 157–169.

See also R. Fox, The Caloric Theory of Gases Unapproachable Lavoisier to Regnault (Oxford, 1971), especially pp. 227–248. Petit’s expose on the history of machines is discussed in C. Proverb. Gillispie, Lazare Carnot savant (Princeton, 1971), 107–111.

Robert Fox