Victor Regnault

Henri Victor Regnault (21 July 1810 to 19 January 1878), known throughout his life as Victor Regnault, was a French chemist and physicist best known for his careful measurements of the thermal properties of gases. Born in Aix-la-Chapelle, he moved to Paris at the age of eight after the death of his parents, entered the École Polytechnique in 1830 and graduated from the École des mines in 1832. Working under Justus von Liebig at Giessen he synthesized several chlorinated hydrocarbons, among them vinyl chloride in 1835 and carbon tetrachloride in 1839, and he was appointed professor of chemistry at the University of Lyon. He held the chair of chemistry at the École Polytechnique from 1840 and a professorship of physics at the Collège de France from 1841, and from 1843 compiled tables on the properties of steam that inspired Charles Algernon Parsons to develop the steam turbine. As director of the porcelain works at Sèvres from 1854 he designed thermometers, hygrometers and calorimeters, and found that gases do not all expand equally when heated and that Boyle's law is only an approximation. He mentored William Thomson, was an amateur photographer and the founding president of the Société française de photographie, and received the Rumford Medal of the Royal Society.