Illustrated Astronomical Treatise
Copied by Jamal al-Din Ibn Isma’il Ibn ‘Assam al-Din Mecca
Dated Saturday 4 Dhu’l Hijja AH 976/ 21 May 1569 AD

Persian and Arabic manuscript on paper, 63 folios, 17 lines of black naskh script to the page, copious marginal notes and drawings, in later marbled cardboard binding
16 x 10.1 cm

This is an illustrated compilation of works and theories on mathematics and astronomy, referring to the work of the famous medieval Islamic scientist, Nasir al-Din al-Tusi (d. 1274). It consists of two short opening chapters explaining the measurement of surface area using geometric formulas, then two longer additional treatises on the stars, planets and planetary motion. Subjects covered include the calculation of sunset and sunrise, the size of the earth, the moon and distance to it, and the distance between the sun and the planets. Further sections are devoted to the ‘static planets’, the movement of the spheres and eclipses. The work is illustrated with a number of finely executed explanatory drawings including geometric shapes, stars, planets, their relationship to earth, and the planetary motions.

Copious notes exist in the margins, and are commentaries and additional notes on the main text, and include references to the work of al-Tusi.

Astronomy was one of the most important subjects in medieval Islamic science. As daily life centred on the times of prayer and the sighting of the moon, it was imperative for medieval scholars to understand the relationship between the earth, the sun, the moon and planetary motion in order to calculate effectively the time of day and the days of the month. Islamic astronomy was based heavily on the classical and pre-Islamic traditions, and major works on astronomy, including that of Nasir al-Din al- Tusi, used the works of classical scholars, such as Ptolemy’s Almagest, as a basis for study.
The neat personal hand in the present example, which on occasion includes words and sentences that have been crossed out, indicates that this copy was written by an astronomer for his personal benefit. In addition, the small, portable format suggests that this manuscript was designed to be easily transported in a pouch or pocket for easy reference.

An inscription on the final folio states that this manuscript was copied by Jamal al-Din Ibn Isma’il Ibn ‘Assam al-Din, in Mecca, ‘during the night of Saturday, on 4 Dhu’l Hijja 976’, which corresponds to 21 May, 1569.