S62 On the Solar Eclipse predicted by Thales. 



was at all likely to be that mentioned by Herodotus. Ac- 

 cording to his computation, the centre ot the moon's sha- 

 dow in that eclipse entered the earth's disk about N. lat. 

 1° 40', and E. long. 23- irom Ferrol. It proceeded then to- 

 wards the mouths of the Nile; and, traversing the Mediter- 

 ranean, crossed Cyprus, Cilicia, and Cappadocia, and j>*issed 

 over to Trebizond. 



The rev. George Costard, without knowing what M. Ma- 

 yer had done, has drawn nearly the same conclusions ; and 

 has likewise entered into a calculation (from Dr; Halley's 

 tables) of all the eclipses which have been assigned lo this 

 event bv precedincj authors : wiiich may be seen, at length, 

 in the Philosophicarrransactions for 1753. In a subse- 

 quent paper, in the same volume, Dr. Slukcley has given a 

 map containing the paih of the moon's shadow in this 

 eclipse, deduced from the calculations of a Mr. Weaver; 

 and which correspond nearly with Mr. Costard's^ But Mr. 

 Costard has suggested an important correction in his com- 

 putation, by allowing for the moon's acce/eratioii; which 

 does not appear to have been attended to either by M. Maver 

 or Ml". Weave;-: and which throws the route of the moon's 

 shadow too far to the southward to pass over any part of Asia 

 Minor. For, on this supposition (he observes) the iuT)bra 

 of' the moon will leave Africa near Damietta; and, after 

 traversinor the south east corner of the Mediterranean, will 

 enter Syria between Tripoli and Tyre ; and, proceeding 

 across Mesopotamia, between Nisibin and Mosul, -Aill en- 

 ter the Caspian Sea near Ardebil. Notwithstaudii.g this 

 circumst;incc, however, the date here assigned has coiViinued 

 to be received as the ti ue date of the battle of the eclipse by 

 all succeeding chronologisls ; alihough it must be evident, 

 even from these data, that such eclipse could not betotalany 

 where near the place where the battle was prol)ably fought. 



But none of these calculations can have much weight at 

 the present day, since they must have been formed from 

 tables which tlie subsequent improvemcnis in astronomy 

 have shown to be exceedingly defective and incorrect. Even 

 the wftf« motions pf the sun and moon are not given with 

 a sufficient dciiree of accuracy, either in the Rudolphine or 

 Halleian tables, tvi enable iis to determine, with any tole- 

 rable correctness, their true niean place of conjunction at so 

 remote a period: neiihtr can the lunar equaiioiis, there 

 given, be safely depended upon. The scciiiar variations 

 also are wholly omitted : and these must have an important 

 effect in all inquiries of this kind, since they increase in 

 proporlion to the period of time elapsed. 



Under 



