In 1723 he became a professor in the College
de France. He was well known as an astronomer and a mathematician, and
wrote in defense of Descartes's theory of vortices (1728, 1729). He also
contributed to the methods of finding prime numbers (1705).

[481] "Deserves not only to be printed, but to be admired as a marvel of
imagination, of understanding, and of ability."

[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