Émilie du Châtelet
Gabrielle Émilie Le Tonnelier de Breteuil (17 December 1706 – 10 September 1749) was a French mathematician, physicist, and author. Her most celebrated achievement is considered to be her translation of and commentary on Isaac Newton's work Principia Mathematica. The translation, published posthumously in 1759, is still considered the standard French translation. Her commentary includes a profound contribution to Newtonian mechanics—the postulate of an additional conservation law for total energy, of which kinetic energy of motion is one element.