R.13.21 (Wren Library, Trinity College Cambridge)
The treatise consists of a preface and two discourses.
On the Divisions of the Celestial Bodies
On the Spheres or Firmaments
On the Aspects of Terrestial Bodies
A commentary on al-Mulakhkhaṣ fī al-hayʼah al-basīṭah of Jighmīnī, Maḥmūd ibn Muḥammad, d. 1221?
Persian Naskhi handwriting
Both works are copiously illustrated with diagrams in red and black, showing the cycles and position of the heavenly bodies, the theory of eclipses etc.
Funding of Cataloguing
Trinity College Cambridge