[ 393 ] 
tion ; P EP' E' P the circumference whofe diameter is 
the earth’s equator, E E' or P P . Let E E' be perpen- 
dicular to P P’> and in the equator. Let 1 1 be per- 
pendicular to C S , and affome this diameter IT for the 
leaver to which all the moments are to be referred. 
The motion of any point, as g , towards the fun, is 
g 
=-j. By refolving this motion into two, one accord- 
Sg 
ing to gC y the other parallel to C S ; the motion ac- 
cording to g C has no tendency to make the point g 
turn round the centre C. The motion of the pointy 
ill r 1 c mi i S SC S y. S C 
parallel to C o will be =; x tt— or ■ — ; but the 
sg 1 S S S 
& 
motion of the centre C according to CS is =-. j 
SC 
therefore the relative motion of the point g, in regard 
i ^ - S x S C S ever 1 
gard to the centre C, is -==- 77-^ or b X b L x 
s £ 
b C 
The moment of the point £ to turn about the centre 
C, will therefore be S x S C x f =L- — =L- )xg*CI, 
5 { sg sc y 
the moment being the product of the motion by the 
mafs of the body, and by the arm of the leaver. 
And this moment caufes the point I to approach to- 
wards the fun, when it is pofitive, or when S C is 
greater than S g j and caufes the point I to recede 
from the fun . when it is negative, or when Sg is 
greater than S C. 
D d d 
It 
