In the relations of social and civil life Lavoisier was exemplary; and he rendered essential service to the state in several capacities. He was treasurer to the Academy, and introduced economy and order into its finances: he was also a member of the board of consultation, and took an active share in its business. When the new system of measures was in agitation, and it was proposed to determine a degree of the meridian, he made accurate experiments on the dilatation of metals, in conjunction with Laplace (1782), to ascertain the corrections due to changes of temperature in the substances used as measuring rods in those delicate operations. By the National Convention he was consulted on the means of improving the manufacture of assignats, and of increasing the difficulty of forgery. He turned his attention to matters of rural economy, and, by improved methods of cultivation, on scientific principles, he increased the produce of an experimental farm nearly one half. In 1791 he was invited by the Constituent Assembly to digest a plan for simplifying the collection of taxes: the excellent memoir which he produced on this subject was printed under the title of ‘The Territorial Riches of France.’ He was likewise appointed a Commissioner of the National Treasury, in which he effected some beneficial reforms. During the terrors of Robespierre’s tyranny, Lavoisier remarked that he foresaw he should be stripped of all his property, and accordingly would prepare to enter the profession of an apothecary, by which he should be able to gain a livelihood. But the ignorant and brutal ruffians who were then in power had already condemned him to the scaffold, on which he was executed, May 8, 1794, for the pretended crime of having adulterated snuff with ingredients destructive to the health of the citizens! On being seized, he entreated at least to be allowed time to finish some experiments in which he was engaged; but the reply of Coffinhall, the president of the gang who condemned him, was characteristic of the savage ignorance of those monsters in human form:—“The Republic does not want savans or chemists, and the course of justice cannot be suspended.” Lavoisier in person was tall and graceful, and of lively manners and appearance. He was mild, sociable, and obliging; and in his habits unaffectedly plain and simple. He was liberal in pecuniary assistance to those in need of it; and his hatred of all ostentation in doing good probably concealed greatly the real amount of his beneficence. He married, in 1771, Marie-Anni-Pierrette Paulze, a lady of great talents and accomplishments, who after his death became the wife of Count Rumford. [Illustration] SYDENHAM.