k 
PHYSICAL ann LITERARY. 185 
call {pring tides. Further the velocity with 
which ‘fupiter revolves on his axis, and the 
greatnefs of his body, muft contribute to the 
greatnefs of thefe tides, and of the inunda- 
tions produced by them. 
In Jupiter's fyftem, the theory of gravity 
difcovers itfelf in fome particulars more ma- 
nifeftly than in any other part of the general 
fyftem. © ‘fupiter is the only body that is, to 
fenfe, {pheroidical; the axis being lefs than 
the diameter of the equator by~;. Poffibly 
we may, by farther obfervations, difcover the 
effects of the tides likewife; or rather may 
learn, that effects already vifible and known 
proceed from them. 
_ Tue action of the fatellites upon one an- 
other produces fome irregularities in their 
Sic ; and from this it is fuppofed that 
_ their eclipfes do not anfwer accurately to the 
times computed from the tables. But there 
is another fource, I believe, of their irregu- 
larities. ‘Yupiter’s figure differs confiderably 
from a fphere; and the gravitatation towards 
him is not inverfely as the {quare of the di- 
ftance from his center. Now this variation 
4 . 
rom the regular courfe of gravity may pro- 
«* se . . . 
uce fome inequalities in their motions. And, 
> 
-. wee Be age & in 
\ p ~ 
