508 Mr. milner on the 
in contact with B, have its center of gravity a little above 
the center of gravity of b, and is aCted upon by the 
greater accelerating force ; in this cafe we may conceive 
how the action of a may qifturb the motion of b, and in 
the fame way how the hard particle c may receive a 
fmall motion from the actions of a and b. Then this 
motion mult be extremely little compared with the 
whole motions of a or b, and fill a great deal iefs if c 
be ftrongly connected with a fixing of hard particles 
along the line ce, fo that c cannot be moved without the 
whole line ce turning round the immoveable center E. 
Now if a, B, and c, be fuppofed hard particles firmly 
connected to the lever ae, then it is plain that the velo- 
city of c, whatever it is, muft be in proportion to that of 
a and b as their refpeCtive diftances from e the center of 
motion, and this, whatever the impulfive forces are with 
which a and b are urged in their refpeCtive directions. 
The body c being ftill fuppofed void of gravity, let 
the bodies a and b be urged by forces perpendicular to 
ae in any fmall equal times through the unequal fpaces 
s and s, and let the magnitudes of the bodies be repre- 
fented by a, b, and c refpeCtively. Then the fpace 
through which a is actually urged in that time will 
eafily appear from mechanics to be reprefented by 
a 
Ax 
