0?i the Solar Eclipse predicted Inj Thales. 3 05 



Uncler these circumstances, and in order to set this ques- 

 tion at rest, as far as it can now be done by the aid of as- 

 tronomical science, I have been induced to re-calculate the 

 elements of the several eclipses, above alluded to, from the 

 new Tables Astronnmiqiies, lately published by the Bureau 

 des Longitudes in France. In these tables, the mean mo- 

 tions of the sun and moon are given with the greatest ex- 

 actness for the most distant periods : and, by the successive 

 labours of Mayer, Mason, and Burg, the lunar equations 

 are carried to an astonishing correctness; which, together 

 with the secular variations deduced from the formid« of 

 M. Laplace, enable us to determine the true place of the 

 sun and moon with considerable accuracy for many cen- 

 turies prior to the Christian sera. These calculations, at 

 full length, together with a map containing the paths of the 

 moon's shadow in the several eclipses there alluded to, are 

 sent with this paper for the inspection of the Members of 

 the Royal Society, should they be desirous of entering more 

 fully mto the detail. The substance of those inqiuries I 

 shall now proceed to lay before them. 



The eclipse, which is supposed to have been that alluded 

 to by I'liny, happened May 2Sih, 58.5 B. C: and the time 

 of the ecliptic conjunction was at 2" 38' 22" in the after- 

 noon, mean time at Greenwich, or 2" 46' 24" apparent \.\rt\s. 

 The elements were as follow : 



True longitude of the luminaries P 29^41'' 4" 



Sun's declination, north 20 23 I7 



■ semi-diamelcr 1 .5 43 



Moon's semi-diameter 1 6 43 



equatorial parallax 61 13 



horary motion from the sun . 35 29 



■ true latitude 12 39 



" horary motion in latitude ... 3 30 



By a projection of this eclipse, T find that the sun was 

 centrally eclipsed on the meridian, about the middle of the 

 Atlantic ocean, in N. lat. 33.;° and W, long. 43°. The 

 centre of the moon's shadow then proceeded t^o the parallel 

 ot N. lat. 40^, in \V. long. 13- ; where, turning to the 

 southward, it crossed Spain, and traversed the course of the 

 Mediterranean. By a trigonometrical calculation I have 

 ascertained that tlic sun set centrally eclipsed on the borders 

 of the Ked Sea in N. lat. 28'^ T, and E. long. 35° 2'. So 

 that at no time was this eclipse central in or near any part 

 ot Asia iVlmor. It happened likewise ten years after the 

 'Jcath of Cyaxarcs, according to the received chronolopv- 

 With respect to the eclipse which happened Octobe°r 1st, 



583 B.C. 



