Hemarks on Ancient Eclipses. 347 



the year of the Julian period 4383, on the 20th day of Sep- 

 tember, a Utile before midRight, or A.C. 331, when Alexander 

 the Great overthrew Darius, and decided the fate of all Asia. 



D. H. M. 

 A.C. 331 D Arbela September 20 20 9 



Solar equation for 416 years, viz, 



747-331=416 .. + 3 4 16 



Equated time . . 24 25 



This eclipse returned visible at Paris 



A.D. 582 }) Paris September 17 12 41 



Solar equation 3 4 16^ , !« ^ 



^ 7 0/ •• + ]^ 



16 



27 16 57 

 Lunar diflference — 4 



Equated time , , 23 16 57 

 The difference between the equated dates of these eclipses is 

 therefore seven hours twenty-eight minutes. 

 The second return was 



D. H. M, 



A.D. 1494 5 Eclipse September 14 19 45 



Solar equation added to the former +17 4 16 



32 9 

 Difference for two periods . . — 8 



Equated time . . . . 24 9 



Therefore the second return of the eclipse seen at Arbela hap- 

 pened within sixteen minutes of time at two periods, or 1824 

 years distance. The year A.D. 1494 we see does not stand af- 

 fected by the reformation of the Nicene calendar, although it 

 may be corrected from that date, but from the epoch of the Na- 

 bonassarean aera; and hence it should appear that the astrono- 

 mical calendar remained unaltered until after ages. 



If we correct the date of the eclipse A.D. 1494, by the rule 

 on wliich the Gregorian calendar was corrected AD. 1582, the 

 difference will Ite found nine days to be added, and the corrected 

 dale will correspond with the above, thus : 



D. H. M. 

 A.D. 1494 ]) Eclipse September 14 19 45 



-i- 9 



Corrected date .. .. 23 19 45 



Thus we see the equations here assumed are verified by se- 

 veral eminent examples. [To be continued.] 



F f 2 LIV. JV/c- 



