[ 4'9 ] 
trary diminini according as they recede from the 
Equator, and approach the Poles. Now it is manifeft, 
that all the parallel Circles circulating round different 
Points of the Axis in the fpherical Vortex^ as well 
as in the cylindrical, tend to recede only from thefe 
different Points of the Axis, round which they cir- 
culate j becaufe a Body cannot tend to recede from 
any Centre but that of its Circulation. In a Word, 
in order to make a Vortex fpherical, which was 
cylindrical, they have but proportionally fhortened 
the parallel Circles. But let the Radius of a Circle 
be ever fo much fhortened or lengthened, that will 
not change the Direction of its dilatative Effort. I 
am miftaken ! an imaginary Line is going to change 
the Diredlion of the axifugal Force. This Force, as 
all agree, has for its Direction the Radius I C, in the 
Circumference whereof it is the Radius 5 but the 
Direflion IC is oblique to CE the Tangent to the 
Sphere ; therefore it changes, according to the general 
Law of an oblique Shock, into the Determination 
IE or O C relative to the Centre O. 
But if Lines may be imagined, and that nothing more 
is requifite to realize them, than Points that cor- 
refpond to them 5 we fhall have fome of all forts in 
the Vortex: We fhall have oblique Lines on the 
Radius O A, a perpendicular one, and fome more 
or lefs oblique, on the Radius I C, and by that means 
we fhall be able to determine nothing. Let us grant 
however, that there is a Tangent to the Sphere CE, 
at the Point C, and let us fee if it will be a fufficient 
Reafon for decompofing the centrifugal Force I C 
into a central Force IE or O C. For that Purpofe 
I ask, What are the Points that compofe this Tan- 
H h h gentr 
