Kitab al-Tabsirah fi al-Hay' ah wa al-Flak (The Book of Enlightenment in Cosmology and Orb), Kitab al-Hay' ah wa al-Flak (The Book of Cosmology and Orb), Kitab Mukhtasar al-Kharqi fi 'Ilm al-Hay' ah al-Musama bi al-Tabsirah. IE TCD MS 1523

[1] Digitised version of IE TCD MS 1523, a copy of an astronomical treatise by 'Abd al-Jabbar ibn 'Abd al-Jabbar al-Kharaqi. The manuscript may date to the 12th century or afterward. Codex, ink, and colours on paper, 64 folios. Arabic text in naskh script. The text is divided into two parts. The first comprises twenty-two chapters outlined by the author where he explains the structure of the universe and the locations of the various celestial bodies (fols. 4r-4v). Some chapters are further subdivided into sections on the sphericity of celestial bodies and explanations of natural phenomena like the solar and lunar eclipses. The author provides an introductory section on defining some astronomical terms (4v-6v). There are many illustrative astronomical diagrams of orbs, zodiac signs, the planets, and the lunar eclipse (fols. 5v, 10r, 12r, 20v, 24v, 29v, 35v, 36v, 37v, 40r, 40v, 41v). The second part comprises 14 chapters outlined on fol. 49v that marks the beginning. It focuses on the division of the Earth and includes the seasons related to the zodiacal signs and constellations. This part also includes diagrams on distances, climates, and the Qibla (direction of Muslim prayer) (fols. 50v, 52v, 58r, 60r, 61r). The author dedicates his treatise to the Seljuk vizier Abu al-Hasan Ali ibn Nasir al-Din who was in the service of Sultan Sanjar (r. 1118-57) (fol. 1v). In the manuscript, al-Kharaqi goes against Ptolemy's astronomical theory in the Almagest that stipulates the movement of the planets in imaginary circles. His alternative model builds on Ibn al-Haytham referenced in fol. 4r and proposes that the planets are supported by and move within two parallel surfaces like a tube (fols. 4r and 7v). The manuscript contains annotations that further elaborate al-Kharaqi{u2019}s theories in the marginalia (e.g. 2v-3r, 4v-5r, 12v). The annotator compares the manuscript to another mentioned as Kitāb al-Qaḍi (24v: انتهي الي هنا و ابتدي في مقابله الكتاب بكتاب القاضي/ I end here and I start comparing this book to the book of Qaḍi). It is not clear who al-Qaḍi exactly is, but it could be Nūr al-Dīn ibn Ishạq al-Biṭrūjī (died c.1204; also know as Alpetragius in Latin), an Andalusian Arab astronomer and qaḍi (judge) who also went against Ptolemy's astronomical theory and authored a book with a similar title to al-Kharaqi. His work was known and studied in the Latin west from the 13th to the 16th centuries. The colophons indicate three variants of the book title. Two are indicated at the beginning: Kitāb al-Tabșirah fī al-Hay' ah wa al-Flak (The Book of Enlightenment in Cosmology and Orb), Kitāb al-Hay' ah wa al-Flak (The Book of Cosmology and Orb), and one at the end: Kitāb Mukhtașar al-Kharqi fī 'Ilm al-Hay' ah al-Musama bi al-Tabșirah. Folio 64v is possibly a letter and not part of the manuscript. The hand is different and difficult to read. At the end of the manuscript, the author's name is indicated in the colophon as Baha' al-Din Abi Mohamed al-Kharaqi. There is confusion in historical records in general between two Kharaqis with some sources conflating both. One is Shams al-Dīn al-Kharaqi (1138-39) and another is our manuscript author, Abd al-Jabbar ibn Abd al-Jabbar Ibn Baha' al-Din al-Kharaqi (d. 1158-59). Some library catalogues that contain copies of the same manuscript mention the two names in relation to it. Also, the manuscripts bearing the same title authored by one are attributed to the other, thus adding to the confusion.