Shihab al-Din Abu'l-Abbas Ahmad ibn Rajab ibn Tibugha 'Ibn al-Majdi' (d.1447 AD), Irshad al-ha'ir ila takhtit fadl al-da'ir (Guide to the Right Path for the Perplexed in Drawing [Lines] of Surplus of Turn'). Treatise on drawing horary lines on the sundials in three parts: on horizontal sundials; on vertical sundials; on oblique sundials, copied by 'Ali bin Hasan, Near East, dated 886 AH/1481 AD

Arabic manuscript on thick polished paper, 53 leaves plus 2 flyleaves, 17 lines to the page, written in Naskh script in brown ink, marginal glosses and numerous charts and diagrams, later brown leather binding with vestiges of earlier binding with tooled geometric decoration pasted down

In fair overall condition, marginal paper repairs, particularly to opening and closing leaves, waterstaining throughout, as viewed.
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This astronomical work is split into three parts: on horizontal sundials; on vertical sundials and on oblique sundials. Other copies can be found in Berlin, Cairo, Istanbul, Leiden, Rabat and Tunis. See also B.A. Rosenfeld & E. Ihsanoglu, Mathematicians, Astonomers & Other Scholars of Islamic Civilisation and Their Works (7^th-19^th c.), Istanbul, 2003, p.276, no.815 and Brockelmann II 158-159. The manuscript to hand can be considered an early copy written around thirty-five years after the death of the author in 1447 AD. There appears to be no copy of this work in the British Library.

The main work in this manuscript is also bound with a treatise on the astrolabe by Badr al-Din Abu ' Abdullah Muhammad Ibn Muhammad Ibn Ahmad al-Misri al-Dimashqi (1423-1506), grandson (from the daughter) of Jamal al-din al-Mardini and a pupil of Ibn al-Majdi. He was known by the name 'Sibt (Ibn Bint) al-Mardini' and lived in Damascus and Cairo. He was also the timekeeper of al-Azhar Mosque in Cairo, and died there in 1506. Rosenfeld and Ihsanoglu list only one other copy of the work in Sarajevo (551/6) under the title, Risalah fi  'amal bi'l-astrulab, Treatise on Operations with the Astrolabe, (see pp.293-298, no.873).

The colophon of the additional work bears the signature of Muhammad Ibn Ahmad al-Makhzumi al-Shusi. There are seven works by the author but not this one in the British Library (see C. Baker, Subject Guide to the Arabic Manuscripts in the British Library, London, 2003, p.373).