182 ESSAYS ann OBSERVATIONS 
ing the centers of the fun and Fupiter, which | : 
we fuppofe perpendicular to the orbit of the 
earth, while the earth is in the folftice T. 
Then, if Fupiter be at I, and the fun at §; 
the angle PTS will be the complement of the 
fun’s greatef{t declination, or of the angle 
contained by the ecliptic and equator: but if 
Fupiter be at z, ad the fun at /; the angle 
PT/ will be the complement of this declina- 
tion, and thefe would differ by the angle 
ST/, which, (becaufe CS is nearly equal to 
a femidiameter of the fun) might amount 
to 32’. 
But, becaufe the angle contained by the 
orbits of fupiter and the earth is fmall, the 
right line CS is feen very obliquely from the 
earth, and the variation of the obliquity thence 
arifing is fmall. The angle CTS is nearly 
to the inclination of wpiter’s plane to the ecli- 
ptic, as the femidiameter of the fun to the di- 
ftance of the earth from the fun: or the angle 
CTS is aboutz*—~of that inclination; there- 
fore ST/; which is equal to 2CTS, may be 
fomewhat more than a minute. And this. 
may be fufficient to account for any variation 
that it is yet difcovered by aftronomers. But, — 
fince it may exceed one minute, it appears 
that 
