The meteoroscope (Greek: μετεωροσκόπιον or ὄργανον μετεωροσκοπικόν; Arabic: dhāt al-ḥalaq, ‘<instrument> with rings’) is an armillary sphere used for observational as well as computational purposes and consisting of nine rings (thus different from the seven-ring instrument described in Almagest V.1). Ptolemy’s treatise on the meteoroscope was known through indirect sources only, until it was recently discovered in a Greek palimpsest (see Gysembergh et al.). A commentary or paraphrase attributed to Theon of Alexandria is extant in Arabic (see Lorch). This text does not survive in Latin.

Bibl. K. Manitius, Procli Diadochi Hypotyposis astronomicarum positionum, Leipzig, 1909, 198-200; A. Rome, ‘L’Astrolabe et le Météoroscope d’après le commentaire de Pappus sur le 5^e livre de l’Almageste’, Annales de la Société Scientifique de Bruxelles 47 (1927), 77-102: 90-102; R. Lorch, ‘The “Meteoroscope” Attributed to Theon of Alexandria. A Study of the Arabic Sources’, in I. International Congress on the History of Turkish-Islamic Science and Technology. İstanbul Teknik Üniversitesi, 14-18 September 1981. Proceedings, Istanbul, 1981, I, 33-38; J. L. Berggren, A. Jones, Ptolemy’s Geography. An Annotated Translation of the Theoretical Chapters, Princeton-Oxford, 2000, 61-62; V. Gysembergh, A. Jones, E. Zingg, P. Cotte, S. Apicella, ‘Ptolemy’s Treatise on the Meteoroscope Recovered’, Archive for History of Exact Sciences 77 (2023), 221-240.

Modern ed. ---