Γεωγραφικα 2.1.18

2.1.18

φησὶ δὲ ὁ Ἵππαρχος κατὰ τὸν Βορυσθένη καὶ τὴν Κελτικὴν ἐν ὅλαις ταῖς θεριναῖς νυξὶ παραυγάζεσθαι τὸ φῶς τοῦ ἡλίου περιιστάμενον ἀπὸ τῆς δύσεως ἐπὶ τὴν ἀνατολήν, ταῖς δὲ χειμεριναῖς τροπαῖς πλεῖστον μετεωρίζεσθαι τὸν ἥλιον ἐπὶ πήχεις ἐννέα, ἐν δὲ τοῖς ἀπέχουσι τῆς Μασσαλίας ἑξακισχιλίοις καὶ τριακοσίοις (οὓς ἐκεῖνος μὲν ἔτι Κελτοὺς ὑπολαμβάνει, ἐγὼ δʼ οἶμαι Βρεττανοὺς εἶναι, βορειοτέρους τῆς Κελτικῆς σταδίοις δισχιλίοις πεντακοσίοις) πολὺ μᾶλλον τοῦτο συμβαίνειν. ἐν δὲ ταῖς χειμεριναῖς ἡμέραις ὁ ἥλιος μετεωρίζεται πήχεις ἕξ, τέτταρας δʼ ἐν τοῖς ἀπέχουσι Μασσαλίας ἐνακισχιλίους σταδίους καὶ ἑκατόν, ἐλάττους δὲ τῶν τριῶν ἐν τοῖς ἐπέκεινα, οἳ κατὰ τὸν ἡμέτερον λόγον πολὺ ἂν εἶεν ἀρκτικώτεροι τῆς Ἰέρνης. οὗτος δὲ Πυθέᾳ πιστεύων κατὰ τὰ ἀρκτικώτερα τῆς Βρεττανικῆς τὴν οἴκησιν ταύτην τίθησι, καί φησιν εἶναι τὴν μακροτάτην ἐνταῦθα ἡμέραν ὡρῶν ἰσημερινῶν δέκα ἐννέα, ὀκτωκαίδεκα δὲ ὅπου τέτταρας ὁ ἥλιος μετεωρίζεται πήχεις· οὕς φησιν ἀπέχειν τῆς Μασσαλίας ἐνακισχιλίους καὶ ἑκατὸν σταδίους, ὥσθʼ οἱ νοτιώτατοι τῶν Βρεττανῶν βορειότεροι τούτων εἰσίν. ἤτοι οὖν ἐπὶ τοῦ αὐτοῦ παραλλήλου εἰσὶ τοῖς πρὸς τῷ Καυκάσῳ Βακτρίοις ἢ ἐπί τινος πλησιάζοντος· εἴρηται γὰρ ὅτι κατὰ τοὺς περὶ Δηίμαχον συμβήσεται βορειοτέρους εἶναι τῆς Ἰέρνης τοὺς πρὸς τῷ Καυκάσῳ Βακτρίους σταδίοις τρισχιλίοις ὀκτακοσίοις· προστεθέντων δὲ τούτων τοῖς ἀπὸ Μασσαλίας εἰς Ἰέρνην, γίνονται μύριοι δισχίλιοι πεντακόσιοι. τίς οὖν ἱστόρηκεν ἐν τοῖς ἐκεῖ τόποις (λέγω δὲ τοῖς περὶ Βάκτρα) τοῦτο τὸ μῆκος τῶν μεγίστων ἡμερῶν ἢ τὸ ἔξαρμα τοῦ ἡλίου τὸ κατὰ τὰς μεσουρανήσεις ἐν ταῖς χειμεριναῖς τροπαῖς; ὀφθαλμοφανῆ γὰρ πάντα ταῦτα ἰδιώτῃ καὶ οὐ δεόμενα μαθηματικῆς σημειώσεως, ὥστε συνέγραψαν ἂν πολλοὶ καὶ τῶν παλαιῶν τῶν τὰ Περσικὰ ἱστορούντων καὶ τῶν ὕστερον μέχρι καὶ εἰς ἡμᾶς. πῶς δʼ ἂν ἡ λεχθεῖσα εὐδαιμονία τῶν τόπων ὡμολόγητο τοῖς τοιούτοις ἐν τῷ οὐρανῷ φαινομένοις; ἐκ δὲ τῶν εἰρημένων δῆλον ὡς καὶ σοφῶς ἀντιλέγει πρὸς τὴν ἀπόδειξιν, ὡς ἰσοδυναμούντων τῶν ζητουμένων λαμβάνοντος πρὸς τὸ ἀποδεῖξαι τὸ ζητούμενον.

Hipparchus narrates that at the Dnieper and [the north of] Keltica, during the whole of the summer nights there is one continued twilight from sun-set to sun-rise, but at the winter solstice the sun never rises more than nine cubits above the horizon. He adds that this phenomenon is yet more remarkable in regions 6300 stadia north of Marseilles, (these regions he supposes to be peopled by Kelts, but I believe are inhabited by Britons, and 2500 stadia north of Keltica,) where the sun at the winter solstice rises only six cubits above the horizon. That at 9100 stadia north of Marseilles it only rises four cubits, and not so much as three in the countries beyond, and which I consider much farther north than Ierne. However, Hipparchus, on the authority of Pytheas, places them south of Britain, and says that the longest day there consists only of 19 hours; while in countries where the sun rises but four cubits above the horizon, and which are situated 9100 stadia north of Marseilles, the day has 18 hours. Consequently [according to his hypothesis] the most southerly parts of Britain must be north of these regions. They must therefore be under the same parallel, or almost the same, as the parts of Bactriana next to the Caucasus, which I have shown are, according to the followers of Deimachus, 3800 stadia farther north than Ierne. Now if we add this to the number between Marseilles and Ierne, we shall get 12,500 stadia. But who ever made known to us that, in those parts, I mean, in the vicinity of Bactra, this was the duration of the longest day, or the height which the sun attains in the meridian at the winter solstice? All these things are patent to the eyes of every man, and require no mathematical investigation; therefore they certainly would have been mentioned by numerous writers both amongst the ancients who have left us histories of Persia, and by the later writers too, who have carried them down to our own time. How, too, would their fertility, which I have described above, harmonize with such a latitude? The facts here advanced are sufficient to give an idea of the learned manner in which Hipparchus attempts to controvert the reasoning of Eratosthenes by mere petitiones principii.