HEAT. 81 



be philosophically regarded, it can come, however, as 

 little under consideration as the weight of the aether. 



393. The fusion of bodies is a diminution of the fixity 

 of their poles, their further evaporation, and thus an 

 approximation to indifference or the apolarity of gather. 

 Heat is the actual retrogression of matter into aether ; 

 light is only the efficient of this transition. 



394. As heat becomes originally excited, so must it 

 be always excited ; two causes for one effect are impos- 

 sible. The excitation of heat by oxydation takes place 

 in the same way as by light, namely by polarization and 

 separation therefore of the Indifferent. The generation 

 of heat by chemical processes is based upon the same 

 principle. Lastly, the generation also of heat by com- 

 pression and simple friction is wholly similar to that which 

 is caused by light. In every case they are only polar, and 

 by no means mechanical operations upon matter, whereby 

 the fixity of the poles becomes changed. 



395. It is not a change of cohesion, which the friction 

 mechanically effects, but the act is purely dynamical. 

 The essence of friction consists in the constant renewal 

 of polar change, because thereby an infinite number of 

 projecting points or apices are alternately brought into 

 contact. There is verily no smooth body. 



396. Heat is the transition of light unto darkness ; for 

 it is indifferent aether, only moved. Colours are thus 

 also a conflict of light with heat, and out of this conflict 

 issues the most beautiful, the highest colour, the Red of 

 fire. In fire, the contest between light and darkness has 

 risen to the highest pitch; the aether therefore is also 

 moved to the greatest degree, becomes hot. If the in- 

 difference becomes the maximum, the vital tension then 

 relaxes, the fire is extinguished; finally motion ceases, 

 it is cold and dark. 



397. In matter also light and heat operate against 

 each other. Light deoxydizes, heat oxydizes. If light 

 appear to oxydize, it is only by evoking heat. 



398. Heat is the function of expansion for matter. 

 Every body has a definite degree or amount of expansion 



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