the five arabic revisions of autolycus’ on the moving sphere (proposition vii)

Autolycus’ on the moving sphere is among the earliest greek mathematical works to reach us and was considered a staple of the middle books, to be studied between the elements and the almagest. this was among the many mathematical works translated to arabic in the 3rd/9th century and it was the subject of several translations, redactions, and recensions. analyzing the available copies of alkura almutaḥarrika, five different versions were identified. in this paper, we analyze these five versions, with a focus on the seventh proposition, in order to characterize their relations to each other and to the extant greek text.