[482] Blaise Pascal (1623-1662), the well-known French philosopher and mathematician. He lived for some time with the Port Royalists, and defended them against the Jesuits in his _Provincial Letters_. Among his works are the following: _Essai pour les coniques_ (1640); _Recit de la grande experience de l'equilibre des liqueurs_ (1648), describing his experiment in finding altitudes by barometric readings; _Histoire de la roulette_ (1658); _Traite du triangle arithmetique_ (1665); _Aleae geometria_ (1654). [483] This proposition shows that if a hexagon is inscribed in a conic (in particular a circle) and the opposite sides are produced to meet, the three points determined by their intersections will be in the same straight line. [484] Jacques Curabelle, _Examen des Oeuvres du Sr. Desargues_, Paris, 1644. He also published without date a work entitled: _Foiblesse pitoyable du Sr. G. Desargues employee contre l'examen fait de ses oeuvres_. [485] See page 119, note 233. [486] Until "this great proposition called Pascal's should see the light." [487] The story is that his father, Etienne Pascal, did not wish him to study geometry until he was thoroughly grounded in Latin and Greek. Having heard the nature of the subject, however, he began at the age of twelve to construct figures by himself, drawing them on the floor with a piece of charcoal. When his father discovered what he was doing he was attempting to demonstrate that the sum of the angles of a triangle equals two right angles. The story is given by his sister, Mme. Perier. [488] Sir John Wilson (1741-1793) was knighted in 1786 and became Commissioner of the Great Seal in 1792. He was a lawyer and jurist of recognized merit. He stated his theorem without proof, the first demonstration having been given by Lagrange in the Memoirs of the Berlin Academy for 1771,--_Demonstration d'un theoreme nouveau concernant les nombres premiers_. Euler also gave a proof in his _Miscellanea Analytica_ (1773). Fermat's works should be consulted in connection with the early history of this theorem. [489] He wrote, in 1760, a tract in defense of Waring, a point of whose algebra had been assailed by a Dr. Powell. Waring wrote another tract of the same date.--A. De M. William Samuel Powell (1717-1775) was at this time a fellow of St. John's College, Cambridge. In 1765 he became Vice Chancellor of the University. Waring was a Magdalene man, and while candidate for the Lucasian professorship he circulated privately his _Miscellanea Analytica_. Powell attacked this in his _Observations on the First Chapter of a Book called Miscellanea_ (1760). This attack was probably in the interest of another candidate, a man of his own college (St. John's), William Ludlam.