[ n6 ] 
COR. II. 
When therefore two bodies adting on the arms of a 
lever fuftain each other, if one of them be removed 
farther from the fulcrum, it will preponderate ; but if 
it be brought nearer to the fulcrum, the other weight 
will prevail : becaufe the produdt to which its force is 
proportional will be encreafed in the firft cafe, and. 
diminished in the fecond„ 
COR. III. 
We learn from hence, to find out the center of gra- 
vity of any two bodies joined by an inflexible right 
line; and to prove that its definition will agree to one 
point only in the line. For if a point be taken in the 
line fo that the distances of the bodies from it may 
be inverfely as their weights, that point will be their 
center of gravity, becaufe, when it is fuftained, the 
bodies will be in aequilibrio. But if the line be fuf- 
tainedatany other point, then is the fulcrum removed 
farther from one body and brought nearer to the other 
than it was when the bodies ballanced each other; 
and therefore, by the preceding Cor. that body from 
which it is removed, or which is on the fame fide with 
the center of gravity, will defcend. Consequently 
there is but one point in the line, which being fuf- 
tained, the bodies will continue in aequilibrio, and 
therefore but one' point only can be their center of 
gravity. Hence alfo it appears, that the center of gra- 
vity will always defcend, when it is not diredtly above 
or below the point by which the body is fuf- 
tained. 
I (hall 
