SEC. A III.] OF NATURAL PHILOSOPHY. 235 in the other body, so are the attractions towards the several particles of the iirst body, to the attractions towards the several correspondent particles of the other body ; and, by composition, so is the attraction towards the first whole body to the attraction towards the second whole body. Q,.E.U. COR. 1 . Therefore if, as the distances of the corpuscles attracted increase, the attractive forces of the particles decrease in the ratio of any power of the distances, the accelerative attractions towards the whole bodies will be as the bodies directly, and those powers of the distances inversely. A* if the forces of the particles decrease in a duplicate ratio of the distances from the corpuscles attracted, and the bodies are as A 3 and B 3, and there fore both the cubic sides of the bodies, and the distance of the attracted corpuscles from the bodies, are as A and B ; the accelerative attractions A3 B3 towards the bodies will be as — and — , that is, as A and B the cubic sjides of those bodies. If the forces of the particles decrease in a triplicate ratio of the distances from the attracted corpuscles, the accelerative attracA3 B3 tions towards the whole bodies will be as — and 5--, that is, equal. If the A. tj forces decrease in a quadruplicate ratio, the attractions towards the bodies A3 B3 will be as-— an^ 04' *^at is, reciprocally as the cubic sides A and B. And so in other cases. COR. 2. Hence, on the other hand, from the forces with which like bodies attract corpuscles similarly situated, may be collected the ratio of the de crease of the attractive forces of the particles as the attracted corpuscle recedes from them ; if so be that decrease is directly or inversely in any ratio of the distances. PROPOSITION LXXXVIII. THEOREM XLV. If the attractive forces of the equal particles of any body be as the dis tance of the places from the particles, the force of the whole body will tend to its centre of gravity ; and will be the same with the force of a globe, consisting of similar and equal matter, and having its centre in the centre of gravity. Let the particles A, B, of the body RSTV at tract any corpuscle Z with forces which, suppos-