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Arabus et Latinus

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Work C.1.29

Theon of Alexandria
Commentary on the Almagest


A commentary on the Almagest mixing three Greek sources: Theon of Alexandria for Books I-II, IV and VI-X and XII-XIII; Nicolaus Cabasilas for Book III; and Pappus of Alexandria for Book V. All Greek MSS have a lacuna from the end of Book X to the beginning of Book XII (see Rome, xxi) and this lacuna has also affected all Latin translations which have Books X-XII.


A. Rome, ‘The Calculation of an Eclipse of the Sun according to Theon of Alexandria’, Proceedings of the international congress of mathematicians, Providence, 1950, 209-219; A. Tihon, ‘Le Livre V retrouvé du Commentaire à l’Almageste de Théon d’Alexandrie’, L’Antiquité Classique 55 (1987), pp. 201-218; A. Jones, ‘Theon of Alexandria’s Observation of the Solar Eclipse of A.D. 364 June 16’, Journal for the History of Astronomy 43 (2012), pp. 117-118; J. Christianidis, I. Skoura, ‘Solving Problems by Algebra in late Antiquity: New Evidence from an Unpublished Fragment of Theon’s Commentary on the Almagest’, SCIAMVS 14 (2013), 41-57; J. M. Steele, ‘The Eclipse of Theon and Earth’s Rotation’, in New Insights From Recent Studies in Historical Astronomy: Following in the Footsteps of F. Richard Stephenson, eds W. Orchiston, D. A. Green, R. Strom, Heidelberg-New York, 2015, 47-51.


The Greek text was first published by Joachim Camerarius in 1538 (Basel, Johannes Walderus), as second part to the editio princeps of Ptolemy’s Almagest. The exemplar used is a MS which belonged to Regiomontanus, now MS Nürnberg, SB, Cent. V App. 8. Critical edition by A. Rome, Commentaires de Pappus et de Théon d’Alexandrie sur l’Almageste, Vaticano, 1931-1943, 3 vols. An older edition of Books I-II, together with a French translation was made by N. Halma, Commentaire de Théon d’Alexandrie sur le premier livre de la composition mathématique de Ptolémée, Paris, 1821; N. Halma, Commentaire de Théon d’Alexandrie sur le second livre de la composition mathématique de Ptolémée, Paris, 1821.

Latin translations