LAVOISIER, ANTOINE LAURENT ( French chemist, was born in Paris on Aug. 26, 1743. His father, an avocat au parlement, gave him an excellent education at the college Mazarin, and he studied mathematics and astronomy with N. L. de Lacaille, chemistry with the elder Rouelle and botany with Bernard de Jussieu. In 1766 he received a gold medal from the Academy of Science for an essay on the best means of lighting a large town; and among his early work were papers on the analy sis of gypsum, on thunder, on the aurora and on congelation, and a refutation of the prevalent belief that water by repeated dis tillation is converted into earth. He also assisted J. E. Guettard (1715-1786) in preparing his mineralogical atlas of France. In 1768 he was nominated adjoint chimiste to the Academy, and be came adjoint to Baudon, one of the farmers-general of the rev enue, subsequently becoming a full titular member of ferme generale. Appointed regisseur des poudres in 1775, he abolished the vexatious search for saltpetre in the cellars of private houses, increased the production of the salt and improved. the manufac ture of gunpowder.
In 1778 he started a model farm at Frechine where he dem onstrated the advantages of scientific agriculture. In 1785 he was nominated to the committee on agriculture, and as its secretary drew up reports and instructions on the cultivation of crops, and promulgated various agricultural schemes. Chosen a member of the provincial assembly of Orleans in 1787, he planned the im provement of the social and economic conditions of the commu nity by means of savings banks, insurance societies, canals, work houses, etc. ; and advanced money to the towns of Blois and Romorantin, for the purchase of barley during the famine of 1788. Attached in this same year to the caisse d'escompte, he presented the report of its operations to the national assembly in 1789, and as commissary of the treasury in 1791 he established a system of accounts of unexampled punctuality. He was also asked to draw up a new scheme of taxation in connection with which he produced a report De la richesse territoriale de la France, and he was associated with committees on hygiene, coinage, the casting of cannon, etc., and was secretary and treasurer of the
commission appointed in 1790 to secure uniformity of weights and measures.
Lavoisier's membership of the ferme generale was alone suffi cient to make him an object of suspicion; his administration at the regie des poudres was attacked ; and Marat accused him of putting Paris in prison and of stopping the circulation of air in the city by the mur d'octroi erected at his suggestion in 1787. In August 1792 he had to leave his house and laboratory at the Arsenal. In November the Convention ordered the arrest of the ex-farmers-general, and on May 2, 1794, they were sent to be tried by the Revolutionary tribunal. Within a week Lavoisier and 27 others were condemned to death, and on the 8th of the month Lavoisier and his companions were guillotined at the Place de la Revolution.
Lavoisier's name is indissolubly associated with the overthrow of the phlogistic doctrine that had dominated the development of chemistry for over a century (see CHEMISTRY: History of), and with the establishment of the foundations upon which the modern science reposes.
On Nov. I, 1772, he deposited with the Academy a note which stated that sulphur and phosphorus when burnt increased in weight because they absorbed "air," while the metallic lead formed from litharge by reduction with charcoal weighed less than the original litharge because it had lost "air." The exact nature of the airs concerned in the processes he did not explain until after the preparation of "dephlogisticated air" (oxygen, q.v.) by Priestley in 1774. Then, perceiving that in combustion and the calcination of metals only a portion of a given volume of common air was used up, he concluded that Priestley's new "air" was what was absorbed by burning phosphorus, etc., "non-vital air," azote, or nitrogen remaining behind.