CHEMICAL ATTRACTION. 199 



The proximate agency of caloric in chemical 

 affinity would have been long since recognised, 

 but for the difficulty of comprehending how a 

 self-repulsive agent could become a cause of 

 attraction. But it is self-evident, that if a 

 globule of ice be composed of oxygen, hydrogen, 

 and caloric ; and if there be an attraction 

 between the particles of ice and caloric, they 

 must be held together with a force equal to that 

 attraction ; and so of all other bodies. Besides, 

 if it were demonstrated, that some other aethereal 

 fluid, such as electricity, surrounds the particles 

 of ice, it must have an attraction for them like 

 caloric, or it could not become a bond of union. 

 It therefore follows, that in either case, the 

 effect results from one and the same fundamental 

 law, which involves an identity, or unity of 

 causation. In addition to what was before stated, 

 page 186, the following facts will further illus- 

 trate the manner in which a self-repulsive fluid 

 becomes a bond of union between the particles 

 of ponderable matter, which have no inherent 

 affinity for each other. 



It is well known, that the particles of aether, 

 alcohol, and many other volatile liquids, repel 

 each other with such force, that when the pres- 

 sure of the atmosphere is removed, they fly 

 asunder, and assume the form of elastic vapours, 

 thus presenting the character of an idio-repulsive 

 agent. It is also known that when the particles 



