Louis Le Chatelier (1815–73)

Henri Louis Le Chatelier was a French scientist, engineer and administrator who promoted economic development and solved technical problems in diverse fields, including mining, railways, iron and steel, aluminium smelting and sewage treatment. His research findings and technical manuals were influential.

He studied in Paris at the École Polytechnique and the École des mines. He then took seven months to travel around northern France, Belgium and the German states examining mines and ironworks. He published his findings in the Annales de mines. He entered the government service as a supervisor of mines and quarries across France in 1841. In 1843 he began to work on the question of French railways, examining how a national network should develop and studying German and English railways. He published his conclusions in 1845 and 1851.

He left the administration in 1846 to take an active role as a railway engineer. He worked on the Northern Railway and the Central Railway. In 1848, following derailment accidents, he undertook experiments to study the destabilisation caused by the movement of locomotive pistons. He suspended a locomotive on chains to examine how it oscillated when working without a track. He recommended the use of counterweights on the moving parts and published his findings in 1849.

From 1855 to 1868 he was chief consulting engineer of the investment bank Crédit Mobilier. This had been established by the Pereire brothers and funded new railways and other industrial projects in France, Spain and Austria.

Research by Le Chatelet also supported the birth of the French aluminium industry and the introduction of the Martin-Siemens processes in the iron and steel industries. His son of the same name (1850-1936) became famous as a professor of chemistry.