Petrus Peregrinus de Maricourt

Petrus Peregrinus de Maharncuria ( French Pierre Pelerin de Maricourt; German Peter pilgrims from Maricourt ) was a French scholar of the 13th century. He experimented with magnets and described in 1269 in his treatise Epistola de Magnets as a first polarity.

The Epistola contained the first work ever, a detailed investigation of vibrating compass needles, which are a fundamental component of the dry compass, and a short time later should appear in medieval navigation ( in 1300 ). It is assumed that the Epistola back to magnetic experiments that Peter had already conducted two decades earlier. This can be inferred from observations in several works of Peter's pupil Roger Bacon, who had appeared in the meantime.

However, Peter did not describe nor the use of an oscillating magnetic needle in conjunction with a wind rose so that in the literature a certain tendency to attribute the invention of the dry compass the Italian maritime city of Amalfi, where the medieval tradition according to which the individual components of the dry compass for the first time to 1300 were combined to form a whole, namely to a freely rotatable needle in a glass box, which is provided with a wind rose.