Claude Auguste Lamy (; 15 July 1820 – 20 March 1878) was a French physicist and chemist who discovered the element thallium independently from William Crookes in 1862; as a result, they are considered co-discoverers, although they did not collaborate.
Lamy was born in the commune of Ney in the department of Jura, France in 1820. Lamy's father-in-law was Frédéric Kuhlmann.
After secondary school in Poligny, Dole and finally Paris, Auguste Lamy entered the ÃÂcole Normale Supérieure and was a fellow student of Louis Pasteur; he graduated in 1842. He became a teacher at and again in Lille. In 1845, he was awarded the agrégation in physics and the licencié in natural sciences.
From 1848 to 1850, he began his career as a physics teacher at a college in Lille (following Louis Pasteur there), then at Limoges, then at the ÃÂcoles académiques de Lille from 1852. He defended his doctoral thesis in Paris in 1851. He taught about thermodynamics, industrial physics and hydraulic presses, distillation and explosions.
In 1854 he became a professor at the faculty of sciences of Lille (Université Lille Nord de France). He taught at ÃÂcole des arts industriels et des mines (ÃÂcole centrale de Lille). In 1866 he changed to the ÃÂcole Centrale des Arts et Manufactures (ÃÂcole centrale de Paris).was awarded the chair of physics at the faculté des sciences de Lille in 1854.
He also taught at the ÃÂcole des arts industriels et des mines in Lille (ÃÂcole centrale de Lille) for 11 years before moving to Paris, where in 1865 he was awarded the Chair of Industrial Chemistry at the ÃÂcole centrale des arts et manufactures, as successor to Anselme Payen.
A member of the Société des sciences, de l'agriculture et des arts de Lille, he became president of the Société française de chimie in 1873.
In 1862, in Lille, Claude Auguste Lamy identifies and isolates 14 grams of the element thallium using the spectroscope loaned by his brother-in-law, the chemist Jules Frédéric Kuhlmann. In 1861, however, this chemical element had been previously described by William Crookes who was studying by spectroscopy the light emitted by a heated selenium ore.
He was a member of the board of directors of établissements Kuhlmann from 1870 to 1878, founded by his father-in-law. Lamy died in 1878.