Louis Poinsot

Louis Poinsot was a French mathematician and physicist, born in Paris on 3 January 1777, who was the inventor of geometrical mechanics, showing how a system of forces acting on a rigid body could be resolved into a single force and a couple. He attended the Lycée Louis-le-Grand and in October 1794 entered the École Polytechnique although he failed the algebra section of the entrance exam. In 1797 he left to study at the École des Ponts et Chaussées to become a civil engineer, but discovered his true passion for abstract mathematics and became a mathematics teacher at the Lycée Bonaparte in Paris from 1804 to 1809. He published a number of works on geometry, mechanics and statics, including Théorie nouvelle de la rotation des corps in 1834. He died on 5 December 1859.