No traces of a Greek commentary by Theon on Ptolemy’s treatise On the Meteoroscope (A.8) have been found. The existence of such a work has been assumed on the basis of the attribution to Theon of two copies of an Arabic text (C.5.1) that describes the construction and the use of the meteoroscope. In his Taʾrīkh Ibn Wāḍiḥ, the geographer and historian al-Yaʿqūbī (d. c. 900) provides a detailed description of a work on an instrument with nine rings, which he attributes to Ptolemy together with a treatise on the astrolabe (not known from Greek sources either), the Qānūn (i.e., the Handy Tables), and the Almagest. Since his description of the work on the meteoroscope fully agrees with the extant Arabic manuscripts, but not with the parts of the Greek text of Ptolemy’s original work recently recovered from the palimpsest Milan, Ambrosiana, L 99 sup. (see Gysembergh et al.), the Arabic text in fact cannot stem from Ptolemy himself. According to al-Yaʿqūbī’s table of contents, the work consisted of a section on the construction of the instrument followed by 39 chapters on its use.

Bibl. al-Yaʿqūbī, Taʾrīkh Ibn Wāḍiḥ (ed. HoutsmaM. T. Houtsma, Ibn Wādhih qui dicitur al-Jaʿqubī, Historiae. Pars prior Historiam ante-Islamicam continens, Leiden: Brill, 1883, vol. I, pp. 154–157; tr. Gordon et al.Matthew S. Gordon, Chase F. Robinson, Everett K. Rowson and Michael Fishbein, The Works of Ibn Wāḍiḥ al-Yaʿqūbī. An English Translation, 3 vols, Leiden: Brill, 2018, vol. II, pp. 420–424); Adolphe Rome, ‘L’Astrolabe et le Météoroscope d’après le commentaire de Pappus sur le 5e livre de l’Almageste’, Annales de la Société Scientifique de Bruxelles. Série A, Sciences mathématiques 47/2 (1927), pp. 77–102, here pp. 90–102; Adolphe Rome, Commentaires de Pappus et de Théon d’Alexandrie sur l’Almageste, 3 vols, Roma / Città del Vaticano: Biblioteca Apostolica Vaticana, 1931–1943, vol. I, pp. 4, 6 and 12; vol. II, p. 419; Victor Gysembergh, Alexander Jones, Emanuel Zingg, Pascal Cotte and Salvatore Apicella, ‘Ptolemy’s Treatise on the Meteoroscope Recovered’, Archive for History of Exact Sciences 77 (2023), pp. 221–240.

Modern ed. None.