370 ON PHYSICAL DATA 



NEW THEORY OF AGGREGATION, 



If, as before stated, we denote the law of 

 attraction of a particle of matter by f(a:) ; and 

 the law of repulsion by ^(.?')- 



Then we shall have for the effective force of 

 the particle 



f(^) $(A-) _ Y(x) 



¥(x) is a quantity which must be obtained by 

 means of induction from many well conducted 

 experiments upon particular material substances. 

 It would be a matter of considerable difficulty to 

 ascertain the law of attraction f(cr) and the law 

 of repulsion *(cr) in each individual particle of 

 matter ; but fortunately, the knowledge of these 

 laws, so far as the motion of a body subject to 

 the differences of their forces is concerned, can 

 be of no use whatever, because Y(x) and — F(.r) 

 will give the absolute forces of the particle 

 when the attractive or repulsive forces prevail 

 respectively. 



