Petrus de Dacia (mathematician)

Petrus de Dacia, also called "Philomena" and "Peder nattergal" (Peter Nightingale), (ca 1230s-1289) was a Danish scholar, mainly working in Paris and Italy. He was an author of New Latin works on calendar, astronomy and arithmetics. He published a calendar of new moon dates for the years 1292 - 1367. In 1292, he published a book on mathematics that contained a new methods for the calculation of cubic root. He also described a mechanical instrument to predict solar and lunar eclipses as seen from Paris.

;SourcesRasch, G. (1932) Petrus de Dacia, pp. 12-15 in: Meisen, V. Prominent Danish Scientists through the Ages. University Library of Copenhagen 450th Anniversary. Levin & Munksgaard, Copenhagen