In what country was the man who originally proposed Le Sage's theory of gravitation in 1690 born?
Nicolas Fatio de Duillier Nicolas Fatio de Duillier {'1': ", '2': ", '3': ", '4': "} (also spelled Faccio or Facio; 16 February 1664 – 12 May 1753) was a Swiss-born mathematician, natural philosopher, and inventor. He spent much of his adult life in England and Holland. Fatio is known for his work on the zodiacal light problem in astronomy, for originating the "push" or "shadow" theory of gravitation, for his close association with both Christiaan Huygens and Isaac Newton, and for his role in the Newton v. Leibniz calculus controversy. He also invented and developed the first method for fabricating jewel bearings for mechanical watches and clocks.
Émilie du Châtelet Gabrielle Émilie Le Tonnelier de Breteuil, Marquise Du Châtelet (] ; 17 December 1706  – 10 September 1749) was a French natural philosopher, mathematician, physicist, and author during the early 1730s until her untimely death due to childbirth in 1749. Her most recognized achievement is her translation of and commentary on Isaac Newton's book "Principia" containing basic laws of physics. The translation, published posthumously in 1759, is still considered the standard French translation today. 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.