De revolutionibus orbium coelestium have begun work on his new system by that time. Most historians believe that he wrote the "Commentariolus" after his return from Italy, possibly only after 1510. At this time, Copernicus anticipated that he could reconcile the motion of the Earth with the perceived motions of the planets easily, with fewer motions than were necessary in the "Alfonsine Tables", the version of the Ptolemaic system current at the time. In particular, the heliocentric Copernican model made use of the Urdi Lemma developed in the 13th century by Mu'ayyad al-Din al-'Urdi, the first of the Maragha astronomers to develop a non-Ptolemaic
The House of the Rising Sun Like many classic folk ballads, "The House of the Rising Sun" is of uncertain authorship. Musicologists say that it is based on the tradition of broadside ballads, and thematically it has some resemblance to the 16th-century ballad "The Unfortunate Rake". According to Alan Lomax, "Rising Sun" was used as the name of a bawdy house in two traditional English songs, and it was also a name for English pubs. He further suggested that the melody might be related to a 17th-century folk song, "Lord Barnard and Little Musgrave", also known as "Matty Groves", but a survey by Bertrand Bronson showed