# Elementa astronomia 17-2

Geminus, Elementa astronomia, Cap. VI.Περὶ ἡμέρας καὶ νυκτός.. Ancient Greek.

Canonical: https://interlinea.aeterna-institute.org/library/greek/geminus/elementa-astronomia/17-2

τοῦ γὰρ πόλου κατὰ κορυφὴν ὑπάρχοντος ἑξαμηνιαίαν τὴν νύκτα καὶ τὴν ἡμέραν γίνεσθαι συμβαίνει. τρίμηνος μὲν γὰρ γίνεται, ἐν ὅσῳ ὁ ἥλιος χρόνῳ ἀπὸ τοῦ ἰσημερινοῦ κύκλου, ὃς δὴ καὶ τὴν τοῦ ὁρίζοντος ἐπέχει τάξιν, ἐπὶ τὸν θερινὸν τροπικὸν κύκλον παραγίνεται, ἑτέρα δὲ τρίμηνος, ἐν ᾗ ἀπὸ τοῦ θερινοῦ τροπικοῦ ἐπὶ τὸν ὁρίζοντα καταντᾷ· καὶ πάντα τοῦτον τὸν χρόνον ὑπὲρ γῆν κύκλους παραλλήλους ἐνεχθήσεται.

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Geminus, Elementa astronomia, ed. Charles Manitius. Text: The Greek Library, from the Perseus Digital Library and other open sources, CC BY-SA 4.0. Changes: apostrophes normalised and the text divided into reading sections by Interlinea.
License: CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/). Source: https://thegreeklibrary.pages.lisn.upsaclay.fr/works/tlg1383.tlg001.local001/.