Charles de Bouelles

c. 1470-c. 1553

French Mathematician

French priest Charles de Bouelles, whose name is variously rendered as de Boville, Bovillus, Bovelles, and Bouvelles, was responsible for a number of contributions to mathematics. Most notable among these were his work on the quadrature, or squaring, of the circle, and his writings on perfect numbers. He also published the first book on geometry written in French, and conducted an early study of the cycloid, the shape generated by following a fixed point on the circumference of a circle that rolls along a straight line.

Little is known about Bouelles's early life, except that he came from an aristocratic family in the town of Saucourt, located in the Picardy region of France. He studied in Paris until about the age of 25, part of this time under the noted educator Jacques Lefèvre d'Etaples (c. 1455-1536), but left in 1495 after a new outbreak of the Plague. For more than a decade, he traveled throughout Switzerland, Germany, Italy, Spain, and other parts of Europe before returning to France and the priesthood in 1507. His first appointment was as a canon at the cathedral of Saint Quentin, followed by a stint in the town of Noyon, where he also served as a theology professor.

Thanks in large part to the patronage of Charles de Hangest, an official at Noyon, Bouelles was free to engage in mathematical investigations. His first mathematical text appeared as Geometricae introductionis in 1503, though it proved so popular that translations in French and Dutch eventually made their appearance as well—a remarkable feat at a time when virtually all scientific material was published exclusively in Latin.

In Geometricae, Bouelles addressed the ageold problem of squaring the circle, which concerned the attempt to map the area of a circle onto a square of equal size. Thanks to the highly accurate determination of pi in circulation today, the quadrature of the circle is no longer a challenge, but in Bouelles's day and afterward, it continued to bedevil mathematical scholars.

Bouelles in 1510 published Liver de XII numbers. The latter addressed the subject of perfect numbers, or those integers which are a sum of all their factors excluding the number itself: for instance, 6 = 1 + 2 + 3, and 28 = 1 + 2 + 4 + 7 + 14. During the following year, he published Le livre de l'art et science de géométrie, the first known work on geometry in French. Later years saw the publication of Prover biorum vulgarium libri tres (1531) and Liber de differentia vulgarium linguarum et gallici sermonis varietate (1533). Bouelles died in Noyon at about the age of 83.

JUDSON KNIGHT