Draft of an introduction to a work on the calendar describing among other things a method for putting together a Jewish calendar based on the idea that the calendar repeats exactly every 247 years. The introduction also announces two chapters on equinoxes and solstices (the tequfot): one easy and approximate and another precise but complicated. Recto also includes a calendar for 1180/1–1190/1 CE. Verso contains three additional texts: 1) calendar calculations for the years 1180/1-1182/3 CE, including Hijra dates written with Coptic numerals; 2) a mnemonic for the date when prayer for dew should be replaced with prayer for rain; 3) the end of the treatise on calendar by Josiah b. Mevoraḵ al-ʿĀqūlī based on the idea that the Jewish calendar repeats itself exactly every 247 years, copied here in a hand different from the rest of the texts.Condition: Torn, holes, rubbedLayout: 22 lines + marginalia (recto); various lines (verso)