Conformément aux observations d'Hipparque

"The Papyrus Fouad inv. 267A, a document of exceptional importance for the history of ancient astromony, consists of a fragment of a treatise written in Alexandria around 130 A.D. The preserved part, which occupies the recto and verso of a single folio, deals with the Sun, whose longitude is calculated according to three different years: the sidereal year, the "mean year" of 365 and 1/4 days, and the tropical year."--