In science, Jean Hachette (1769-1834) was a French mathematician, a professor of the École Polytechnique, noted for his 1811 Elementary Treatise on Machines, in which, supposedly, he was the first to propose a dynamic unit of ‘kg∙m’, being a type of energy (although he likely didn't use this word) as a unit of measurement for all natural phenomena. [1] Hachette's unit may have been a precursor to French mathematician and engineer Gustave Coriolis' 1829 proposal of the unit of dynamode (1,000 kg∙m) as a measure of mechanical effect. [2]

References
1. (a) Hachette, Jean N.P. (1811). Elementary Treatise on Machines (Traité élémentaire des Machines). Paris.
(b) Fernández-Galiano, Luis and Carino, Gina (translator) (2000). Fire and Memory: On Architecture and Energy (Hachette, pgs. 47, 183-184, 186, 190). MIT Press.
2. Coriolis, Gustave. (1829). Calculation of the Effect of Machines, or Considerations on the Use of Engines and their Evaluation (Du Calcul de l'effet des Machines, ou Considérations sur l'emploi des Moteurs et sur Leur Evaluation). Paris: Carilian-Goeury, Libraire.

Further reading
● Cardwell, Donald S.L. (1971). From Watt to Clausius: the Rise of Thermodynamics in the Early Industrial Age (Hachette, pgs. 165-66, 189). Cornell University Press.

External links
● Jean Hachette – Wikipedia.