This manuscript contains an anonymous astronomical treatise that most likely was produced in the 18th or early 19th century. The only date preserved in the manuscript is 1232 AH (1816), which is found on the last written page (folio 65 verso), together with a list of book titles and a short note that appears to be crossed out. The terminus ante quem (latest possible date) for production of the manuscript is thus 1816. The note seems to have been written in a different, less elegant, and most likely later hand from that of the main text. Entitled Šarḥ‘alā tašrīḥ al-aflāk (The explanation on the Anatomy of the Heavens by al-‘Āmilī), the work is based on the astronomical treatises written by Bahāʾ al-Dīn al-ʿĀmilī, a 16th-century polymath who was born in Lebanon and spent his life in Safavid Iran. An accomplished philosopher and theologian, al-‘Āmilī is regarded as one of the first astronomers to consider the possibility of the positional rotation of the earth. This and other innovative ideas, which al-ʿĀmilī developed autonomously from the Western tradition, were expressed in his work Tašrīḥ al-aflāk, the subject of the extensive commentary in the present manuscript. The treatise opens with a long introduction devoted mostly to invocations and prayers to the Creator of the Heavens and to the praise of Bahāʾ al-Dīn al-ʿĀmilī. The work is then divided into aqṭāb (singular quṭb, meaning pole or axis), each of which includes various sub-sections (fuṣūl, singular faṣl). The work is presented as a complete treatment of astronomical science, focusing in particular on the sun and the moon and their movements. The manuscript includes some explanatory drawings, such as the one that appears at folio 14 verso, but it seems that the illustrations are incomplete. Spaces on some of the folios (such as at folio 42 versoand 59 verso) were left blank, presumably intended for drawings that were never realized.