Petrus de Dacia, also called Philomena and Peder nattergal (Peter Nightingale), was a Danish scholar who lived in the 13th century. He worked mainly in Paris

Paris

Paris is the capital and largest city in France, situated on the river Seine, in northern France, at the heart of the Île-de-France region...

 and Italy

Italy

Italy , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...

, writing in Latin

Latin

Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...

. He published a calendar of new moon

New moon

In astronomical terminology, the new moon is the lunar phase that occurs when the Moon, in its monthly orbital motion around Earth, lies between Earth and the Sun, and is therefore in conjunction with the Sun as seen from Earth...

 dates for the years 1292 - 1367. In 1292, he published a book on mathematics that contained a new methods for the calculation of cubic roots. He also described a mechanical instrument to predict solar and lunar eclipse

Eclipse

An eclipse is an astronomical event that occurs when an astronomical object is temporarily obscured, either by passing into the shadow of another body or by having another body pass between it and the viewer...

s as seen from Paris.

Editions

• Corpus Philosophorum Danicorum Medii Aevi vol. X, ed. Fritz Saaby Pedersen. Copenhagen 1983.