COSMIC PHILOSOPHY 



are alike in constitution, — into heat and elec- 

 tricity, when they are unlike. In violent colli- 

 sions, as in the chipping of stones with a mason's 

 chisel, the arrested molar motion is partially 

 changed into light. And when an iron bar is 

 suspended in the magnetic meridian and vio- 

 lently struck or continually jarred, a portion of 

 the arrested motion reveals itself as magnetism. 



The transformation of heat into molar mo- 

 tion may be seen in the rise and fall of the mer- 

 cury in the thermometer, or in the driving of 

 a piston by the molecular dilatation of aque- 

 ous vapour. When lime is introduced into an 

 atmosphere of burning hydrogen, we see the 

 conversion of heat into light. And when the 

 heated ends of zinc and copper wires are brought 

 together, we see heat generating electric cur- 

 rents. Conversely, electricity conducted down 

 a lightning-rod is partly converted into heat ; 

 and in the bright flashes which are followed by 

 claps of thunder, we witness electric energy 

 partly consumed in originating light. 



The phenomenon commonly called light is 

 but a species of a mode of solar energy which 

 may be called radiance or actinism, and which, 

 according to the manner in which it affects our 

 senses, is known as radiant heat, as light, or as 

 the energy which works changes in the da- 

 guerreotype-plate and in the leaves of plants. 

 The difference between the higher rays of the 



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