In 1830, Regnault was admitted to the École Polytechnique, and in 1832 he graduated.
Gallery of Henri Regnault
University of Leiden, Leiden and The Hague, South Holland, Netherlands
Regnault received a doctoral degree in mathematical and physical sciences from the University of Leiden.
Career
Gallery of Henri Regnault
1865
Henri Regnault, French chemist
Gallery of Henri Regnault
Professor Henri Victor Regnault (21 July 1810 – 19 January 1878) was a French chemist and physicist best known for his careful measurements of the thermal properties of gases.
Gallery of Henri Regnault
Henri Victor Regnault, 1810 – 1878. French chemist and physicist. From Les Merveilles de la Science, published 1870.
Gallery of Henri Regnault
Henri Regnault, French chemist
Achievements
The extremely careful experimental research that allowed the separate obtaining of each one of the different products was carried out in the schematic apparatus shown in this picture.
Membership
Awards
Rumford Medal
1848
Regnault was a recipient of the Rumford Medal.
Legion of Honor
1850
Regnault received the Legion of Honor.
Copley Medal
1869
Regnault was a recipient of the Copley Medal for outstanding achievements in research in any branch of science.
Matteucci Medal
1875
Henri Victor Regnault received the Matteucci Medal, which is an Italian award for physicists, named after Carlo Matteucci from Forlì. It was established to award physicists for their fundamental contributions.
Henri Victor Regnault received the Matteucci Medal, which is an Italian award for physicists, named after Carlo Matteucci from Forlì. It was established to award physicists for their fundamental contributions.
Professor Henri Victor Regnault (21 July 1810 – 19 January 1878) was a French chemist and physicist best known for his careful measurements of the thermal properties of gases.
The extremely careful experimental research that allowed the separate obtaining of each one of the different products was carried out in the schematic apparatus shown in this picture.
Connections
Son: Alex-Georges-Henri Regnault
Alexandre-Georges-Henri Regnault (31 October 1843 – 19 January 1871) was a French painter.
Henri Victor Regnault was a prominent French chemist and physicist. He was among the most famous French experimental scientists of the nineteenth century who studied physical properties of substances and their mixtures and also done some interesting research on the hygrometry and respiration of animals.
Background
Henri Victor Regnault was born on July 21, 1810, in Aix-la-Chapelle, France (now Aachen, Germany). Regnault was left an orphan at an early age; his father, an officer in Napoleon’s army, died in 1812 in the Russian campaign and his mother died shortly afterward. Regnault moved to Paris at the age of eight, following the death of his parents.
Education
A close friend of Regnault’s father supervised his education and then found employment for him in a draper's shop in Paris, where, despite considerable financial hardship, he took lessons for the entrance examination of the Ecole Polytechnique. Admitted there in 1830, he graduated with distinction two years later and studied for two more years at the Ecole des Mines in Paris before traveling extensively in Europe to study mining techniques and metallurgical processes.
Later he received a doctoral degree in mathematical and physical sciences from the University of Leiden.
After short periods of research under Liebig at Giessen and Boussingault at Lyons, Regnault returned to the Ecole Polytechnique as an assistant to Gay-Lussac in 1836 and in 1840 succeeded him in the chair of chemistry.
Also in 1840, he was elected to the chemical section of the Academie des Sciences, but his interests were already turning to physics and it was at the College de France, where he became a professor of physics in 1841, that he performed his most important experimental work for the next thirteen years. From 1854 he lived and worked at Sevres as director of the famous porcelain factory; and he was still engaged on research there when, in 1870, all his instruments and books were destroyed by Prussian soldiers.
In his chemical work, nearly all of which dates from 1835 to 1839, Regnault followed no unified program of research. It was, however, his contributions in organic chemistry, most notably his studies of the action of chlorine on ethers and the research that led him to the discovery of vinyl chloride, dichloroethylene, trichloroethylene, and carbon tetrachloride which quickly won him an international reputation and the high esteem of such chemists as Liebig and Dumas.
Regnault’s early work in physics arose directly from his chemistry. Encouraged by Dumas, who had long advocated the measurement of specific heats as a means of investigating the atomic composition of substances, he began with a systematic experimental study of the specific heats of a wide range of solids and liquids. In the course of this work, which occupied him from 1839 to 1842, he conclusively demonstrated the approximate nature of Dulong and Petit's law and confirmed the validity, within the same limits of accuracy, of F. E. Neumann’s extension of the law from elements to compounds.
In 1842, with his reputation as an experimenter established, Regnault was appointed by the minister of public works to redetermine all the physical constants involved in the design and operation of steam engines; it was then that he began the research on the thermal properties of gases for which he is now best known.
In fact Regnault did far more than was asked of him; and in nearly thirty years of painstaking experiments, all generously financed from government funds, he not only provided the standard data that practicing engineers were to use for several decades but also subjected the laws governing the physical properties of gases to a thorough and long-overdue reexamination. His most important conclusions, all reached by 1853, concerned Dulong and Petit’s law, which was shown to be only approximately true even for gases (thus contradicting Dulong’s own conclusion on this point); the expansion coefficient, which Regnault measured to an unprecedented degree of accuracy and which he showed to vary with the nature of the gas; and Boyle’s law, the deviations from which he investigated in great detail.
Speculation and discussions of the theory are noticeably absent from Regnault’s published work, as they are from his surviving notebooks. But in 1853 he declared his acceptance of the principle of the conservation of energy; and later he measured the mechanical equivalent of heat, although with only moderate success. In declaring his support for the principle, Regnault stated that he had subscribed to the mechanical theory of heat “for a long time” and that he had been led to it independently through his own experiments.
A comment made in 1854 by a former pupil, Ferdinand Reech, which suggests that Regnault had been won over to the new ideas only with great difficulty, seems more reliable, however (Machine a air d'un nouveau systeme, 1854). For there is certainly no evidence, other than Regnault’s own testimony, to indicate that he arrived at the principle independently, although in many ways he was well poised to make the discovery.
As Dumas later regretted, Regnault was too cautious. In the quality of his meticulous experimental work, which he always conducted on the grand scale, he was unrivaled in his own day; and his compilations of data provided an indispensable tool for the pioneers of thermodynamics. Yet he lacked the intellectual capacity to participate in a truly creative way in the momentous developments in physics in the mid-nineteenth century.
Regnault belonged to the Academy of Sciences since 1847. He was also a member and became the founding president of the Société française de photographie in 1854.
Personality
Regnault was also an avid amateur photographer. He introduced the use of pyrogallic acid as a developing agent, and was one of the first photographers to use paper negatives.
Physical Characteristics:
The death of his son Henri late in the Franco-Prussian War left Regnault a broken man, and his last years were clouded by grief and personal disability.
Quotes from others about the person
"Those who are unacquainted with the details of scientific investigation have no idea of the amount of labor expended in the determination of those numbers on which important calculations or inferences depend. They have no idea of the patience shown by a Berzelius in determining atomic weights; by a Regnault in determining coefficients of expansion; or by a Joule in determining the mechanical equivalent of heat." — John Tyndall
Interests
photography
Connections
Regnault was the father of Henri Regnault, the great painter, author of Salome, and the equestrian portrait of General Prim, killed gloriously and so prematurely, on January 19, 1871, at Buzenval, by a Prussian bullet, barely twenty-five years old.