101 Rev. J. B. Emmett on the [Feb. 



laws of corpuscular action with the Newtonian philosophy. In 

 the present communication, more obscure phenomena, in which 

 the agency of eleclricity, caloric, and attraction, are concerned, 

 come under examination. 



The relative magnitudes of the particles of matter, and the 

 ratio of their forces of attraction, must first be determined. If 

 the centripetal force of a particle of matter belong to its surface 

 only, which I have supposed in the former communications, the 

 weight of a particle of matter = F x I)- {D being the diameter 

 of the particle, F its force of attraction]. 



Therefore, atomic weight {W} = F x D^ (a) 



AlsoF = ~ (b) 



And D = v' ^ (c) 



If the centripetal force be competent to the entire particle, the 

 following formulae result : 



W = F X D^ (1) 



AlsoF = g (2) 



And 



^ = {/t (3) 



I 



Under a given volume, the number of particles is as =-; the 

 surface of each particle is as D- ; therefore, the quantity of sur- 

 face contained in a solid of given magnitude is as ^i ; hence, upon 



the first supposition, the weights of equal volumes, or specific 



p 

 gravity {S} is as ^. 



••• S = -g- (d) 



Also F = S . D (e) 



AndD = ^ (/) 



But upon the second supposition, F = S . . . . (4) 

 Make (b) = (e), 



Then ^ = S.D.-.D = <^f (A) 



Make (2) = (4), 



And^=S.-.D 



= v/t (^) 



In each case, therefore, the diameter of a particle of a solid is 

 as the cube root of the atomic weight, divided by that of the 

 specific gravity. This is only an approximation to the truth ; 

 for the particles have to be supposed similarly situated ; and we 



