Execution of Lavoisier

Execution of Lavoisier

Antoine Laurent Lavoisier, generally considered the founder of modern chemistry, was executed on May 8, 1794, in Paris, France. In addition to his scientific career, Lavoisier had held many public offices, but during the revolutionary Reign of Terror (1793–94) he fell foul of the radical new government and lost his life as a result.

Lavoisier was born on August 26, 1743, in Paris, France, the son of a wealthy lawyer. He was educated at the Collège Mazarin and became a member of the prestigious Academy of Sciences in 1768. Lavoisier was a pioneer in the field of chemical research, proving by experiment that the active agent in combustion was oxygen rather than a mysterious substance called phlogiston, as contemporary theory mistakenly held. He investigated the composition of air and of water, and provided evidence to support the law of the conservation of matter, which holds that even though matter may change its form in the course of a chemical reaction, the amount of matter involved remains exactly the same. Lavoisier's carefully calibrated experiments were models of their kind; he is credited with having made chemistry a quantifiable science. Lavoisier wrote several books, one of which, Treatise on Chemical Elements (1789) helped formulate the concept of an element as a substance that could not be broken down further by ordinary means.

Lavoisier was active in public life as well. During the last decades of the French monarchy he held such posts as head of the national gunpowder works; he also served on committees to investigate and improve conditions in the hospitals and prisons of Paris and to reform the archaic French tax system. A political liberal, he was an alternate deputy to the Estates-General of 1789, which initiated the French Revolution and the overthrow of the monarchy. During the early years of the Revolution, Lavoisier published a report on the nation's finances and helped set up the metric system of standardized weights and measures.

However, Lavoisier had been a member of the Fermiers-Généraux, a company of private agents who collected taxes for the monarchy. As the French Revolution became more and more dedicated to wiping out all traces of the old regime, the Fermiers-Généraux came under suspicion. Twenty-eight members were arrested, and on May 8, 1794, they were arraigned before a revolutionary tribunal and condemned to death. Lavoisier had been in the middle of an experiment to determine the role of oxygen in human respiration when the police burst in, and his only request to the court was that they postpone his execution until this series of experiments was completed. “The Republic has no need of scientists,” replied the court, dismissing his plea. Lavoisier went to the guillotine the same afternoon. “It took only an instant to cut off that head,” said his friend, the mathematician Joseph Lagrange, “though it could take a hundred years to produce such another.”