¹ See Qurra, Thābit Ibn, Œuvres d'astronomie, Éd., trad. et commentaire par Morelon, R., Sciences et Philosophie arabes, Textes et études (Paris, 1987)Google Scholar. This work contains the detailed references and discussion of the questions which, of necessity, are only touched upon briefly in this article.

² See Thābit, , Œuvres d'astronomie, introduction to “Treatise 3,” pp. XLVI–LIII.Google Scholar

³ Respectively “Treatise 1” and “Treatise 2” in Thābit, , Œuvres d'astronomie, introduction pp. XXXVII–XLV, text and translation pp. 1–25, commentary pp. 170–88.Google Scholar

⁴ “Treatise 4” in Thābit, , Œuures d'astronomie, introduction pp. LXXVI–LXXIX, text and translation pp. 68–82, commentary pp. 216–21.Google Scholar

⁵ See Ptolemy, , The Almagest, edition by Heiberg, J.L., 2 vols. (Leipzig, 1898–1903), and English translation by G.J. Toomer, Ptolemy's Almagest (London, 1984), pp. 145–6.Google Scholar

⁶ See Thābit, , Œuvres d'astronomie, p. 78.Google Scholar

⁷ “Treatise 5” in Thābit, , Œuvres d'astronomie, introduction pp. LXXX-XCII, text and translation pp. 83–92, commentary pp. 222–9.Google Scholar

⁸ See The Almagest, ed. Heiberg, I, 272–5 and Ptolemy's Almagest, pp. 176–7.Google Scholar

⁹ “Treatise 6” and “Treatise 7” in Thābit, , Œuures d'astronomie, introduction pp. XCIII-CXVIII, text and translation pp. 93–116, commentary pp. 230–59.Google Scholar

¹⁰ For a detailed discussion of the evolution of this method see Thābit, , Œuvres d'astronomie, pp. XXV-XXX.Google Scholar

¹¹ See the explanation of these elements and their justification in Thābit, , Œuvres d'astronomie, pp. C-CXVII.Google Scholar

¹² “Treatise 8” in Thābit, , Œuvres d'astronomie, introduction pp. CXIX-CXXV, text and translation pp. 118–29, commentary pp. 260–4.Google Scholar

¹³ See Neugebauer, O., “The astronomical origin of the theory of conic sections,” Proceedings of the American Philosophical Society, 93, 3 (1948): 136–8, taken up againGoogle ScholarNeugebauer, O., Astronomy and History, Selected Essays (New York and Heidelberg, 1983), pp. 295–7.CrossRefGoogle Scholar

¹⁴ “Treatise 9” in Thābit, , Œuvres d'astronomie, introduction pp. CXXVI-CXL, text and translation pp. 131–64, commentary pp. 265–91.Google Scholar

¹⁵ Maimonides, Moses, The Guide of the Perplexed, English translation by Shlomo Pines (Chicago, 1963), pp. 324–5.Google Scholar

¹⁶ Ibid., p. 457. These fragments have been commented on in part by Duhem, P., Le système du monde, 10 vols. (Paris, 1913–1959), vol. II, pp. 117–19.Google Scholar

¹⁷ Albert, the Great, Opera omnia, V,1, De cœlo et Mundo, ed. Hossfeld, P. (Cologne, 1970), p. 30, lines 25–30.Google Scholar

¹⁸ See Henquinet, F. M., “Une pièce inédite du commentaire d'Albert le Grand sur le IV^e livre des sentences,” Recherches de Théologie Ancienne et Médiévale, 7 (1935): 263–93, the cited text is on p. 285. There is no trace to this day of the two treatises of Ṯābit whose titles are cited by Albert the Great, neither in Arabic or Latin translation.Google Scholar

¹⁹ See Morelon, R., “Les deux versions du traité de Thābit b. Qurra Sur le mouvement des deux luminaires,” Mélanges de l'Institut Dominicain d'Études Orientales, 18 (1988): 9–44Google Scholar. The text of the fragment is on pp. 28–9, its translation on pp. 32–4, and the commentary on pp. 38–43; see in particular p. 42 and note 13 on the proof from “terrestrial” mechanics which this fragment assumes is known.

²⁰ Manuscript Damascus, Ẓāhiriyya, 4871, fols. 78b-79b, the fragment is on fol. 79a, lines 9–11.

²¹ See Ibn, Yūnus, Kitāb al-zīj al-kabīr al-ḥākimī – Le livre de la grande table hakémite, partially edited and translated by Caussin, edition separate from Notices et extraits des manuscrits de la Bibliothèque Nationale (Paris, Imprimerie de la République, An XII – 1804); for the two fragments below see pp. 99–105Google Scholar; the text had been reviewed against the manuscript and the translation has been re-done. The recipient of the first letter, al-Qāsim b. ‘Ubayd Allāh, died in 291/904, he had succeeded his father, in 289/902, in the post of Vizier of the caliph al-Muktafi; the recipient of the second letter, IsḤaq b. ḥunayn (died in 298/910), is the famous physician and translator from Greek into Arabic.

²² A treatise translated from Arabic and existing only in Latin has been passed down under the name of Ṯābit on this problem of trepidation, see Neugebauer, O., “Thābit Ben Qurra On the Solar Year and On the Motion of the Eighth Sphere,” Proceedings of the American Philosophical Society, 106, 3 (1962): 290–9Google Scholar. But this attribution appears to be false, see Thābit, , Œuvres d'astronomie, pp. XVIII-XIX.Google Scholar

²³ See on this subject the testimony of al-Bīrūnī cited in Thābit, , Œuvres d'astronomie, p. XLIX.Google Scholar

²⁴ See Thābit, , Œuvres d'astronomie, p. 112.Google Scholar

²⁵ See Ptolemy's Almagest, p. 600.

²⁶ See Thābit, , Œuvres d'astronomie, p. 108.Google Scholar

²⁷ See Ptolemy's Almagest, p. 600.

²⁸ Text being edited, this passage in found in the beginning of the second part.

²⁹ Personal correspondence with Mrs A. Duhoux-Tihon.

³⁰ For the development of this theme in the Latin world up to the time of Copernicus, see Lerner, M. P., “L'Achille des Coperniciens,” Bibliothèque d'Humanisme et de Renaissance, 42, 2 (1980): 313–27.Google Scholar

³¹ Edited by A. I. Sabra and N. Shehaby (Cairo, 1971).

³² See, for example, Léon, Gauthier, “Une réforme du système astronomique de Ptolémée tentée par les philosophes arabes du XIII^e siècle,” Journal Asiatique, 14 (1909): 483–510.Google Scholar

³³ See al-‘Urī, Mu'ayyad al-Dīn, Kitāb al-Hay'a – Tārīḫ ‘ilm al-falak al-'arabī, Ed. and Introd. by Saliba, George (Beirut, 1990), pp. 27–9.Google Scholar