BERKELEY AND KANT. 173 



of attraction and repulsion, as if such powers 

 could exist without substance. Not less obscure 

 is the modern doctrine which resolves light, heat, 

 and electricity, into vibrations of some unknown 

 hypothetical aether. Who can grapple with 

 such shadowy and unsubstantial data ? 



It has been already shewn, that caloric is not 

 an effect, condition, or property of other matter, 

 but an all-pervading and independent active 

 principle, without which there could be no vi- 

 brations. Had Bacon, Boyle, Newton, and 

 Hooke, been aware of the law by which aethereal 

 and active matter is attracted and concentrated 

 around the particles of ponderable matter, and 

 thus disguised from the senses, as shewn by Dr. 

 Black, they could never have confounded the 

 cause of heat with motion and vibration ; or had 

 Count Rumford recognised the vast force of 

 attraction by which caloric is concentrated 

 around the particles of iron and other metals, 

 he would not have been at a loss to account for 

 the heat evolved by the friction of boring a 

 cannon. 



It is an exceedingly partial and superficial 

 view of caloric to regard it merely as the cause 

 of temperature, fluidity, vaporization, decompo- 

 sition, &c. ; for it is self-evident that if the at- 

 traction of caloric for metals, ice, and other 

 bodies, augments in proportion as they are de- 

 prived of it, it must be an attractive as well as a 



