FIXED BY ASTRONOMICAL COMPUTATION. 67 



and as the battle was probably fought on the confines of these 

 two empires, I think it will be evident from the preceding ex- 

 tracts, [describing the phenomena of the diminution of light 

 in solar eclipses, as mentioned above,] that no solar eclipse 

 could be the one mentioned by Herodotus, unless it was cen- 

 tral and total in some part of Asia Minor ; that is, the centre 

 of the moon's shadow, in such total eclipse, must have passed 

 over that part of Asia Minor where the contending armies 

 were engaging. Consequently the fact is capable of being 

 verified or disproved by the present state of our knowledge in 

 astronomy." 



The attention of the learned seems first to have been 

 fixed to this point by M. Th. S. Bayer. He consulted an 

 astronomical friend, M. Fred. Christ. Mayer, who showed, 

 that none of the five eclipses, which, down to his time, had 

 been fixed upon by chronologists, could possibly be that al- 

 luded-to by Herodotus. He found, by appropriate calcula- 

 tion, that the eclipse which took place on May 1 8th, 603 B. c., 

 was the only one that was at all likely to be the right. Not 

 many years after, an English Astronomer, the Rev. G. Costard, 

 arrived, independently, at nearly the same conclusion ; but 

 by introducing an important correction into his computa- 

 tion, allowing for the moon's acceleration, he evinced, at the 

 same time, that in this eclipse, her shadow could not pass 

 over any part of Asia Minor. Notwithstanding this circum- 

 stance, however, the date assigned by Mayer continued to be 

 received as the true date of the " battle of the eclipse," by all 

 succeeding chronologists ; although it must be evident, even 

 from the data furnished by Mr. Costard, that the eclipse 

 which then took place could not be total anywhere near the 

 place where the battle was fought. M. Volney, it is true, in 

 his Chronologie d'Herodote, published early in the present cen- 

 tury, discarded this eclipse ; and fixed upon that of February 

 3rd, 626 B.C., but without taking any means of ascertaining 

 whether that could have been total at the scene of conflict. 



Such was the condition of this inquiry, when it was taken 

 up by Mr. Baily, who brought to its determination all the re- 

 sources which modern astronomy could furnish. None of the 

 previous calculations, either on the affirmative or negative 

 side, could be regarded as possessing much weight, at the 

 time he undertook to set the question at rest ; since they had 

 been formed from tables which the subsequent improvements 

 in astronomy had shown to be exceedingly defective and in- 

 correct. In order, therefore, to leave no part of the inquiry 

 undetermined, he computed the course of the moon's shadow 

 for each of the seven eclipses which had severally been as- 



F2 



