354 Mr. vince’s Invejligation of the 
or as Bg : bh, or as j’K. ■: fh ; hence that fpace, or the 
fpace through which the centrifugal force of A will 
draw the lever in the diredtion bh, is equal to Kg ; that 
is, the point k, which is the center of gravity of a 
and b, will be found at g, and confequently the center 
of gravity has preferved its motion uniform in the right 
line Gy, inafmuch as the centrifugal force, adting per- 
pendicularly to the direction of the center of gravity, 
can neither accelerate or retard its motion. In the fame 
manner it may be proved, that the motion of the center 
of gravity is continued uniform in the fame right line, 
whatever be the pofition of the lever. Moreover, as 
the centrifugal force adts in the direction of the lever, 
it cannot alter its angular velocity, which will therefore 
remain as in ip Jo motus initio. If now we. fuppofe 
that to the force impreffed upon a, two other equal 
accelerative forces be communicated to a and b at 
the fame time, it is evident that no alteration can arife 
from the actions of the bodies on each other ; and the 
cafe will then be fimilar to the motion of the bodies, 
fuppofing a Angle force had been impreffed, at any point 
D. The like method of reafoning may be- extended 
to any number of bodies. 
The fame thing may alfo eafily be demonftrated iii 
the following manner. The centrifugal forces of a 
7 and 
