428 TRANS. ST. LOUIS ACAD. SCIENCE. 



the ft from the sun must have been about 5° only. According to 

 Lalande's Tables the longitude of the sun was likewise 3^ 3° 58', 

 and that of the ft 3^ 5° 5'. 



The total eclipse of the moon, and the partial one of the sun, 

 in the loth year of the Peloponnesian war, i.e. -420, of which 

 the latter was seen on January i8th, both being observed by the 

 eye-witness Aristophanes (Nub. 581), belong to the most reliably 

 ascertained eclipses of ancient history ; and yet the ecliptic new 

 moon in —420, Jan. 18, 2h., was, according to our Tables, invisi- 

 ble on our globe, because the X5 lay 17° west of the sun. Even 

 Pingre states that on the said day no solar eclipse was possible in 

 the old world. Consequently the longitude of the X5 must have 

 been shorter by about 5°, which agrees with the aforesaid eclipse. 



Further, the eye-witness Thucydides testifies that the nearly 

 total eclipse of the sun in —429, January 26th, 22d, happened, in 

 Athens, after noon {/xsza jueff/j/x8f)cau) ; consequently the longi- 

 tude of the moon must have been shorter, and the conjunction 

 must have been later by about three hours. 



Herodotus reports that the total eclipse of the sun in Smyrna 

 (Sardes), noticed by the whole Persian army, in —478, Feb. 27, 

 i5h. 30m., coincided with sunrise in Sardes. According to our 

 Tables, however, this eclipse was over prior to sunrise in Sardes ; 

 consequently the longitude of the moon must have been sfiorter, 

 and, again, the conjunction must have been retarded by about 3 

 hours and 20 minutes. 



The whole Roman history bears witness that Rome was found- 

 ed -on the day of the Roman parilia (the vernal equinox), and 

 that during the building of the city an eclipse was seen within the 

 third hour after sunrise. Tarutius narrates that the same eclipse 

 was observed at Teos in Ionia ; our Tables, on the contrary, state 

 that this eclipse was invisible in Rome, even in Asia Minor. In 

 order to obtain a corresponding eclipse, the longitude of the moon 

 in —752, May 25, i6h. must be shortened, and the conjunction 

 postponed by about 3 hours 50 minutes. 



Finally, many eclipses of the sun, reported by ancient authors 

 to have been total, were, according to the present theory of the 

 moon's motions, annular ones. On occasion of the total eclipse 

 in -400, as we have seen (p. 424), the radius of the sun was 

 greater than that of the moon by 10 seconds. 



