Cod.: paper, I+235+I^a ff. (foliated with both Hindu-Arabic numerals in black ink and Arabic-European numerals in pencil, running entirely parallel; quire numbers ‘3’ to ‘8’ in Hindu-Arabic numerals on ff. 11r, 19r, …, 51r). A single clear naskh hand in black; mostly dotted ductus. Book headings and titles in Kufic (‘early ʿAbbāsid’) script, some work and chapter titles in red. Extensive marginalia in another hand in black between ff. 87r–108v and 162v–180v, otherwise hardly any marginalia. A third hand (same as the Arabic-European foliation) added complete titles in pencil (ff. 183r, 191r, 200v, 228r). Diagram lines in red with letters in black. Decorated with illuminated titlepieces filled with arabesque patterns (provided for most books in red, gold and black, displaying Mamluk characteristics). Codex in acceptable condition; moisture and severe mold stains on the edges, not affecting the body text. Dimensions: 245×145 mm, written area: 155×105 mm; 23 lines per page. Brown leather cover pasted on a dark leather cover of a later period, decorated with a central blind-tooled mandorla and pendants surrounded by an elaborated frame (13^th c., probably Mamluk). Type III binding.

Cont.: mathematics and astronomy. — Index: table of contents in a different hand (1r); Apollonius, Kitāb fī Qaṭʿ al-khuṭūṭ ʿalā l-nisab (2r–52v, incomplete); Ptolemaica (53r–80v); al-Kindī, Risāla fī Istikhrāj al-aʿdād al-muḍmara (81r–86v); unidentified mathematical work (86v–89r); Agathon, Kitāb al-Mafrūḍāt (89v–102v; edited in Dold-Samplonius); fragment of Theodosius, Kitāb fī l-Ukar (102v, not listed in the table of contents); Agathon (?), Risāla fī l-Mafrūḍāt (103r–108v, not listed in the table of contents); Thābit b. Qurra, Kitāb fī l-Aʿdād al-mutaḥābba (110r–121v); Ibn al-Ṣalāḥ, Sabʿ maqālāt (122r–160v); al-Qūhī, Rasāʾil handasiyya (161r–182v); collection of anonymous aʿmāl, some incomplete (182v–200r; see Charette & Schmidl); al-Ṣabāḥ, Risāla fī ʿAmal Muḥammad b. al-Ṣabāḥ li-l-sāʿāt al-mabsūṭa bi-l-handasa fī ayy iqlīm aradta (200v–204r); al-Kindī, Risāla fī Īḍāḥ wijdān abʿād mā bayna al-nāẓir wa-marākiz aʿmidat al-jibāl wa-ʿulū aʿmidati-hā wa-ʿilm ʿumq al-ābār wa-ʿurūḍ al-anhār wa-ghayr dhālika wa-hiya tusammā mūrsīṭas (204v–210v); Abū Bakr ibn Abī ʿĀbas, Kitāb fī Akhadh al-abʿād (210v–214v); Ibn Ḥātim al-Nayrīzī, Kitāb fī Maʿrifat ālāt tuʿlam bi-hā abʿād … (215r–224v); Abū Muḥammad al-Rāzī, Kitāb fī Akhadh al-abʿād (225r–227v); anonymous, Maʿrifat saʿat al-mashriq fī kull balad ʿalā mā ʿamala Baṭlamyūs min quṭr al-falak … (228v–231r); al-Khwārizmī, ʿAmal al-sāʿāt fī basīṭ al-rukhāma (231v–235r). Blank: 1v, 228r, 235v.

Bibl.: Defter-i Kütüphane-i Ayasofya, Istanbul: Mahmut Bey Matbaası, 1887 (1304 H.), p. 318; KrauseMax Krause, ‘Stambuler Handschriften islamischer Mathematiker’, Quellen und Studien zur Geschichte der Mathematik, Astronomie und Physik, Abteilung B: Studien 3 (1936), pp. 437–532, pp. 439, 449–450, 455, 461, 467–468, 485–487, 515, 520, 522, and 524; Franz Rosenthal, ‘Al-Kindī and Ptolemy’, in Studi orientalistici in onore di Giorgio Levi della Vida, Roma: Istituto per l’Oriente, 1956, vol. II, pp. 436–456, here pp. 436–437; Yvonne Dold-Samplonius, Kitāb al-Mafrūḍāt li-Aqāṭun. Book of Assumptions by Aqāṭun. Text-critical edition, PhD dissertation, University of Amsterdam, 1977, p. 1; Ashraf A. Akhmedov, Jamal al-Dabbāgh and Boris A. Rozenfeld, ‘Istanbul Manuscripts of al-Khwārizmī’s Treatises’, Erdem 3/7 (1987), pp. 163–186; François Charette and Petra G. Schmidl, ‘Al-Khwārizmī and Practical Astronomy in Ninth-Century Baghdad. The Earliest Extant Corpus of Texts in Arabic on the Astrolabe and Other Portable Instruments’, SCIAMVS 5 (2004), pp. 101–198, here pp. 107–109. — Islamic Scientific Manuscripts Initiative: https://ismi.mpiwg-berlin.mpg.de/codex/354105; Yazma Eserler Veritabanı: https://portal.yek.gov.tr/works/detail/207243. .