Revolving about Fired Aves. Q73 
by the motion of the particles of matter, the other excited by a 
cause producing pressure, resisted by cohesion. Now, according 
to the fundamental principles of mechanics, “the same cause 
Fig. 4. 
acting upon a ‘a body will sei aaleee motion or pressure, ac- 
cording as the body is free or restrained.” And, “if two forces 
act upon the same point of a body in different directions, a single 
force may be assigned which, acting on that point, will produce 
the same results as the united effects of the other two.” Here 
we have two forces acting on each particle of the revolving body, 
but they are resisted by cohesion, therefore when cohesion ceases 
to act, the effect of the two forces must be, according to the the- 
Orem of the composition of forces, to impel itin the direction of 
their resultant, and with an amount of force equal to their me+ 
equivalent ;—and experiment shows the correctness of 
