رسالة على فضل الدائر.

An astronomical treatise on the surplus of the dāʼir, the latter being the distance from a star to the horizon measured on its parallel. Fragment on folio 12, with two charts and the end of a text, appears to be either a later addition or part of a separate treatise. 12 leaves : paper, illustrations ; 222 x 157 (140 x 93) mm.