The Greeks in Bactria and India c9.s2.55

c9.s2.55

Production began in the second century with the astronomer Seleucus,² of Seleuceia-on-the-Erythraean-Sea,³ which stood on the north-east shore of the Persian Gulf somewhere between Charax Spasinu at the mouth of the Tigris and Antioch in Persis (p. 17) on the Gulf of Bushire. Strabo calls him a Chaldean,⁴ but it is incredible, if so, that Greek tradition did not preserve his Babylonian name, as it did that of every other Babylonian astronomer it knew—Kidenas, Sudines, Naburian. Those Greeks, like Artemidorus of Parium, Epigenes of Byzantium, Apollonius of Myndus, who came from the West to study astronomy and astrology in the Babylonian schools used to call themselves Chaldeans as a sort of title of honour;⁵ and this no doubt is what the word means, though it is always possible that the Greeks of Seleuceia on the Persian Gulf were called Chaldeans to distinguish them from those of Seleuceia on the Tigris who were called Babylonians, the designation in either case being territorial; but however that may be, Seleucus was almost certainly a Greek. His precise date cannot be given, but he must at any rate have overlapped the Parthian conquest. He spent his life maintaining, against Hipparchus, the theory of Aristarchus of Samos that the earth went round the sun;⁶ but apparently he had not mathematics enough to correct (as Hipparchus could and should have corrected) Aristarchus' mistaken belief that the earth's orbit was a circle instead of an ellipse. He studied the tides of the Persian Gulf, and his theory of *how* the moon made the tides¹ is of great interest, for he seems to have been groping after something which might with luck have led him to the discovery of gravitation, especially as Babylonian astronomers already had some idea of the sun's attraction;² but more important for my purpose is the light which he and his work throw upon the nature of this forgotten Greek city on the Persian Gulf.