Antoine Lanreut Lavoisier, a French chemist, born in Paris in August, 1743, died on the scaffold, May 8, 1794. He was the son of a rich merchant, studied at the Mazarin college, and learned astronomy from La Caille, chemistry from Rouelle, and botany from Bernard de Jussieu. In 1766 he won a prize from the academy of sciences by his Memoire sur la meilleure manure d'eclairer les rues d'une grande ville. Several other essays, especially his Memoire sur les couches des montagnes, secured him admission to that academy in 1768. To meet the heavy expenditures necessitated by his experiments, he sought and received an appointment as farmer of the public revenue; and he showed himself a skilful administrator no less than an acute philosopher. In 1776 Turgot placed him at the head of the regie des salpetres, and he introduced many improvements into the manufacture of gunpowder. From 1778 to 1785 he gave attention to agriculture, and enriched the science of husbandry by many valuable suggestions. In 1787 he was elected to the provincial assembly of Orleans. In 1788 he became one of the trustees of the bank of discount, and in 1789, as assistant deputy to the constituent assembly, presented an interesting report upon the condition of that institution.

He was a member of the commission on weights and measures in 1790, and took great interest in the preparation of the new decimal system. Being in 1791 one of the commissioners of the treasury, he published his essay De la richesse nationale de la France, in which he presented a plan for the collection of taxes; this essay, which was to be but the forerunner of a complete treatise upon this important subject, entitles him to a high rank among political economists. But the best of his energies had been devoted to chemical investigations, which he pursued with untiring perseverance from 1772 till his death; in 1786 he had published no fewer than 40 essays or memoirs, giving incontrovertible evidence of great logical power and unparalleled acuteness, while successively embodying the principles out of which chemical science was to be renovated. His discoveries and general influence in this branch of natural philosophy are treated in the article Chemistry. His greatest work is his Traite elementaire de chi-mie (2 vols. 8vo, 1789), a synopsis of modern chemistry, in which he exhibits no less ability as a logician than as a natural philosopher.

His physical investigations were also valuable; he wrote an excellent essay Du principe consti-tutif de la chaleur, first printed in the Memoires de l'academic des sciences in 1777. In his later years his attention was mostly turned to applications of chemistry to physiology, and his two Memo ires sur la transpiration des animaux deserve to be particularly noticed. He was collecting all his writings with the ultimate view of remodelling them into a single work, when the course of revolutionary events brought him to a premature end. Dupin, a member of the convention, having on May 2, 1794, introduced an act of accusation against all the farmers of the public revenue, Lavoisier delivered himself up and was imprisoned; on the 6th he was involved in the general sentence of death against the corporation to which he belonged, and two days later he was guillotined. His essays were collected and published by his widow (who afterward married Count Rumford), under the title of Memoires de physique et de chimie, in 2 vols. 8vo. A complete edition of his works has been published under the supervision of the minister of instruction, and at the expense of the government (4 vols., Paris, 1864-'8).