Charles Louis Félix Franchot


Source: After the article of the Association d'études fouriériste et les cahiers Charles Fourier
Title: Franchot, Charles-Louis-Félix
Author: Bernard Desmars


Born September 16, 1809 in Saint-Venant (France), died July 31, 1881 in Ancerville (Meuse). Tax officer, inventor, mechanical engineer, Member of the committee of La Démocratie pacifique between 1843 and 1848. He is also involve in politics by participating in several social movements.

Charles-Louis-Félix Franchot is the son of an officer who fought in the Napoleonic armies and ended his career with the rank of lieutenant colonel. He was made officer of the legion of honor and received the title of Baron of the Empire.
Charles-Louis-Félix Franchot himself is for a time tax controller, in Châteaudun, in the 1830s.

But from the 1840s, The press presents him as an "Engineer" or "Mechanical Engineer" ; he is indeed the inventor of a hot air machine patented in 1838 and also a moderator lamp which ensures him a national fame.

His hot air machine is designed strictly according to the Carnot requirements, and therefore has been the best theoretical hot air engine of the 19th century.
In his patent, Franchot re-invented the regenerator (he called it the calefactor) without knowing the existence of Stirling's economiser that was invented 12 years earlier.

In the following we will present his two main hot air engines:

Franchot also submits to the Académie des Sciences a model of "parachoc" that would be used to cushion shocks in railway collisions. With Tessié du Motay, he filed in 1843 a patent on a tunnel system under the Channel: the two inventors propose to place at the bottom of the sea a cast iron tube consisting of many segments adapting to the submarine relief; wagons could circulate there, driven not by steam locomotives, but by compressed-air machines.

In parallel with his involvement in the social movements, he continues his research; In 1854, the Académie des Sciences recognized the value of his work by awarding him the Montyon prize for mechanics, and in 1855, he received the Legion of Honor, on the occasion of the Universal Exhibition in Paris where his improved hot air engine is exhibited.

With another inventor, François Coignet, who developed agglomerated concretes, he invents the "Franchot concrete mixer".

He retires at Ancerville, a chief town of the Meuse canton of about 2100 inhabitants, situated between Bar-le-Duc and Saint-Dizier; his family is very well established there, his grandfather, then his uncle and his cousin having directed the municipality during most of the first half of the nineteenth century.

In 1875, he inherited a house of his cousin, which he sold in 1879 to the town of Ancerville, which installed the town hall and a school ; it owns in the same locality the domain Saint-Antoine, a property of about 25 hectares consisting of meadows, arable land, woods and ponds (the current "Franchot ponds").

In his will, he bequeaths this domain to the commune at the same time as sums of money to the charity office, to the local band and to the parish.