This research eventually led others to invent the process of photography, and Clément-Desormes is recognized as a contributor in the early history of that industry.

[1] In about 1819, he befriended Sadi Carnot, and the two men developed methods for calculating the maximum amount of energy that could be obtained from a kg of coal.

Clément and Carnot clearly understood the concept of a Mechanical equivalent of heat, and developed formulae for calculating energy efficiency almost 20 years before Mayer and Joule's work on this subject in the 1840s.

Clément-Desormes was a successful young industrialist who was owner or partner in several chemical companies, including one that made sugar from beets.

Some speculate that his sudden death was brought on by a business disagreement concerning payments that were owed to him for successful introduction of a profitable process.