Soon after the establishment in 1794 of the École Polytechnique in Paris, Gaspard Monge had proposed a class on the analysis of mechanisms and described the subject to fellow teachers. When the class was first taught in 1806 by Hachette, Betancourt was among its students. Another student was José María Lanz, whose lecture notes were revised and published together with Betancourt as "Essai sur la composition des machines" (1808; 2nd ed. 1819; 3rd ed. 1840), encouraged to do so by Monge and Hachette. This textbook on machine design became widespread in European universities. It was translated to English as "Analytical essay of the construction of machines" (1820, published by Rudolph Ackermann) and by Thomas Fenwick as "Essays on practical mechanics" (1822) and to German by Wilhelm Kreyher as "Versuch über die Zusammensetzung der Maschinen" (1829).