Treatise for Observers on Constructing the Circle of Projection


This work is a treatise on the important subject of timekeeping. It is a work of technical astronomy, in 19 folios, that begins by emphasizing the religious significance of knowledge of time. It is divided into an introduction, two chapters, and a conclusion. Comprehensive procedures for the construction of tables and their use are provided. The work was completed in 1473 (878 A.H.).

Date Created

Subject Date


Title in Original Language

نزهة الناظر فى نظم خطوط فضل الدائر

Type of Item

Physical Description

10 leaves; 15.5 x 21 centimeters


  • Includes illustrated tables.

Last updated: September 22, 2014