Now it is quite possible to predict eclipses without knowing their true cause, and there is no doubt that the Babylonians actually did so. On the basis of their astronomical observations, they had made out a cycle of 223 lunar months, within which eclipses of the sun and moon recurred at equal intervals of time.[63] This, it is true, would not enable them to predict eclipses of the sun for a given spot on the earth’s surface; for these phenomena are not visible at all places where the sun is above the horizon at the time. We do not occupy a position at the centre of the earth, and what astronomers call the geocentric parallax has to be taken into account. It would only, therefore, be possible to tell by means of the cycle that an eclipse of the sun would be visible somewhere, and that it might be worth while to look out for it. Now, if we may judge from a report by a Chaldaean astronomer which has been preserved, this was just the position of the Babylonians. They watched for eclipses at the proper dates; and, if they did not occur, they announced the fact as a good omen.[64] To explain what we are told about Thales no more than this is required. He simply said there would be an eclipse; and, as good luck would have it, it was visible in Asia Minor, and on a striking occasion. Footnote 63: The first to call attention to the Chaldaean cycle in this connexion seems to have been the Rev. George Costard, Fellow of Wadham College. See his _Dissertation on the Use of Astronomy in History_ (London, 1764), p. 17. It is inaccurate to call it the _Saros_; that was quite another thing (see Ginzel, _Klio_, i. p. 377). [Sidenote: Date of Thales.] 4. The prediction of the eclipse does not, then, throw much light upon the scientific attainments of Thales; but, if we can fix its date, it will give us a point from which to start in trying to determine the time at which he lived. Modern astronomers have calculated that there was an eclipse of the sun, probably visible in Asia Minor, on May 28 (O.S.), 585 B.C.,[65] while Pliny gives the date of the eclipse foretold by Thales as Ol. XLVIII. 4 (585/4 B.C.).[66] This, it is true, does not exactly tally; for May 585 belongs to the year 586/5 B.C. It is sufficiently near, however, to justify us in identifying the eclipse as that of Thales, and this is confirmed by Apollodoros, who fixed his _floruit_ in the same year.[67] The further statement that, according to Demetrios Phalereus, Thales “received the name of wise” in the archonship of Damasias at Athens, agrees very well with this, and is doubtless based on the story of the Delphic tripod; for the archonship of Damasias is the era of the restoration of the Pythian Games.[68] Footnote 64: See George Smith, _Assyrian Discoveries_ (1875), p. 409. The inscription which follows was found at Kouyunjik:— “To the king my lord, thy servant Abil-Istar. * * * * *