One of the three appendixes that were frequently copied at the end of al-Ṭūsī’s Taḥrīr al-Majisṭī (C.1.18) in manuscripts that ultimately derive from an exemplar attributed to Quṭb al-Dīn al-Shīrāzī (cf. C.1.18b and C.1.18c, and see the note on these appendices in the description of C.1.18). Different from the two other appendices, this work does not have a specific title; the title used here was added by a librarian in MS Istanbul, Süleymaniye, Ayasofya 2583. The treatise first illustrates the different configurations of the Mercury model on the basis of twenty figures. These display the position of the epicycle centre with respect to the Earth for the following values of the mean centrum and their opposites: 0°, 45;0°, 60;0°, 68;32°, 88;29,31°, 90°, 93;12°, 120°, 135° and 180°, as well as for the situations in between these values, all with brief explanations. The treatise is completed by three tables. The first of these displays, as a function of the mean centrum, all the intermediate steps of the calculation of the following quantities: the distance of the epicycle centre from the equant point, its distance from the earth, the equation of centre, and the maximum equation of anomaly. Arguments are all the multiples of 15°, the values for which the twenty figures are given, and several other specific values. The second and third tables display for Venus and Mercury the following quantities as a function of the mean centrum (given for every 5 degrees): the equation of centrum, the maximum equation of anomaly, the maximum evening elongations, and the maximum morning elongations. Incipit: Nurīd an nathbitu ikhtilāfāt wuqūʿ al-khuṭūṭ fī l-ashkāl allatī yuʿrifu min-hā awḍāʿ marākiz aflāk ʿuṭārid fī masīrāti-hā.

Text: [Istanbul, Nuruosmaniye, 2941]

(107v) نريد أن نثبت اختلافات وقوع الخطوط في الأشكال التي تعرف منها أوضاع مراكز أفلاك عطارد في مسيراتها ومقادير أبعاد مركز التدوير عن مركزي العالم ومعدّل المسير ومقادير اختلافه الأوّل بحسب الأبعاد المختلفة ومقادير أبعاده العظام أيضًا بحسبها التي هي غايات اختلافه الثاني — (107v) ... وا ك العمود الخارج من مركز العالم على الخطّ الواصل بين مركزي العالم والتدوير ويكون الأشكال بحسب مسير المركز بالحركة الوسطى مبتدئًا من الأوج إلى التوالي هكذا. [diagrams] [tables]

Bibl.: FankhāMuṣṭafā Dirāyatī, Fihristgān-i nuskhahā-yi khaṭṭī-yi Īrān (Fankhā), 45 vols, Tehran: Library, Museum and Documentation Center of The Islamic Consultative Assembly, 20 2011, vol. II, pp. 376–377 and 383; Mª José Parra, ‘A List of Arabic Manuscripts of Naṣīr al-Dīn al-Ṭūsī’s Taḥrīr al-Majisṭī’, Suhayl 16–17 (2018–2019), pp. 251–322, here pp. 254–255.

Ed.: None.