Pierre Hérigone

Pierre Hérigone (1580 to 1643), also known in Latin as Petrus Herigonius, was a French mathematician and astronomer of Basque origin who taught in Paris for most of his life. His only known work is the Cursus mathematicus, a six volume compendium of elementary mathematics in French and Latin published in Paris between 1634 and 1637, which set out an unusually complete system of mathematical and logical notation. Many of its symbols did not survive, but he is credited with early use of a sign for an angle, the symbol for perpendicularity, the less-than sign and a notation for powers written on the same line as the base. He also devised a phonetic alphabet for memorising long numbers and described a goblet shaped camera obscura. He sat on scientific committees, including one that judged Jean-Baptiste Morin plan to find longitude from the Moon motion. A lunar crater, Herigonius, is named after him, and the name Hérigone is thought to be a pseudonym.