MATTER, MOTION, AND FORCE 



three other corollaries, which — as belonging to 

 the transcendental regions of physical science 

 — must be set forth and illustrated before we 

 can profitably begin our synthesis of scientific 

 truths. Let us briefly consider these in their 

 natural order. 



The first of these corollaries is the generali- 

 zation currently known as the " Correlation of 

 Forces." Since each manifestation of force must 

 have been preceded by some other equivalent 

 manifestation of force, it follows that when 

 any specific manifestation appears to terminate, 

 it does not really cease to exist, but is only 

 transformed into some other specific manifes- 

 tation. That we may better apprehend this 

 important truth, let us clear away some of the 

 ambiguity which surrounds the terms commonly 

 employed in the statement of it. The phrase 

 "correlation of forces," which means the corre- 

 lation of sensible motion with heat, light, elec- 

 tricity, etc., implies that heat, light, and electri- 

 city are forces. This is not strictly accurate. 

 Heat and light are modes of undulatory motion, 

 and electricity, with its kindred phenomena, is 

 to be similarly interpreted. Now motion is not 

 force, but one of the manifestations of force ; 

 and so the various modes of motion, molar and 

 molecular, are differently conditioned manifes- 

 tations of force. The force which produces or 

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