( 2©7 ) 
I find the Difpute to be chiefly over what part 
the Back of Aries the Colure pad ; The Words of 
Hipparchus, as from Eudoxus, are (imply, that it pafl o- 
ver the Back, without faying over what ^jtar, or over 
what pare of the Back it pa(f. And the fame Hippar- 
chus ihews, that if it pad over the Star in the middle of 
the Back, it greatly differed from the Situation thereof 
in his time ; and conceiving thence that the ^quifio- 
d:ial Points might have a regrefiive motion, he was 
the firfi; that attempted to define their motion ; but ha- 
ving no Obfervations older than thofe of Timocharis, 
made within lefsthan xoo Years of his own time, and 
very courfe withal, he was not able to determine the 
quantity thereof, but gueft it to be about a Degree in 
lOo Years; which, length of time, and the more cu- 
rious Obfervation of the Moderns, has now proved to 
be I® or rather ijd' per Annum, 
In a word. Sir Jfaac takes the Colure to have pad 
over the middle of the Conftellation of Aries, and ve- 
ry near the Star in the middle of the Back {v Bayer o). 
And F, Souciet will have it, that it pad over the middle of 
the Sign ot Dodecatemorion of Aries, reckoning the Sign 
to begin with the fird Star of the Conftellation ; and 
by confequcnce his Colure mu ft pafs about midway 
between the Rump and fird of the Tayl of Aries 
(e and Bajero ;') which Situation could never be faid 
to be over the Back : But whild Sir Ifaac makes the 
Colure but 36' from the fird Star of Ariei, 
which P, Souciet makes 15 Degrees from it, the 
difference 7^ 24' at per Annum, makes 533 Years 
difference in the refult. 
Let us DOW examine when the Stars in quedion did 
actually pafs under the Colure of the Vernal ^tquinox, 
affuming their places as they are in Mr. Flamfieed's Bri- 
ti(h Catalogue, fitted to the beginning of the Year 1 690. 
E e z He 
