Posted by: Glow-worm PJ15 JUL 2010
Henri Victor Regnault was born on 21 July 1810 in Aix-la-Chapelle. He was orphaned aged eight, and struggled against poverty, having to provide for himself and his sister. He eventually moved to Paris to work as a clerk in a large drapery firm.
He studied in his spare time and when he was 20 qualified for the École Polytechnique, where he showed an aptitude for chemistry.
In 1840, he became chair of chemistry there, concentrating on the relatively new subject of organic chemistry, especially the halogenation of unsaturated hydrocarbons, and he was the first person to synthesise carbon tetrachloride.
He accidentally discovered polyvinyl chloride when the polymer formed as a white solid on the inside of flasks of vinyl chloride that were left in sunlight. The significance of the product was not realised at the time, and it was decades before it became commercially significant.
In 1841 he was given the chair of physics at the Collège de France, and in 1843 the government commissioned him to investigate the properties of steam and publish results that would be of use to steam engineers. The set of extensive numerical tables that resulted led to him being awarded the Romford medal by the Royal Society of London.
He became renowned for work on the specific heats of elements and the thermal expansion of gases, and demonstrated that Boyle’s law is an approximation for real gases. His experimental techniques were thorough and meticulous, allowing him to achieve more accurate results than his predecessors.
He also developed scientific instruments. He invented the air thermometer, and had his own hygrometer named after him .
A keen amateur photographer, he was the founding president of the Société Française de Photographie in 1854. He carried out research on developing techniques, and proposed pyrogallic acid as a developing agent, as well as working on the carbon process, and in 1856 devised an actinometer using silver chloride paper.
Regnault died on 19 January 1878, aged 67.