Tahrir kitab al-manazir. [Optics].
4to (154 x 230 mm). Arabic manuscript on smoothed oriental paper. (45) pp., 11 lines, per extensum. Black ink with red emphases. With numerous red ink diagrams in the margins. Later full black cloth.
An Arabic manuscript of the "Optics" by Euclid, a work on the geometry of vision. According to Euclid, the eye sees objects that are within its visual cone. The visual cone is made up of straight lines, or visual rays, extending outward from the eye. These visual rays are discrete, but we perceive a continuous image because our eyes, and thus our visual rays, move very quickly.
Incomplete, comprising only the first 23 ff. Paper browned; occasional light brownstaining; a paper flaw to the final leaf has been remargined.