CONSTITUENTS OF THE UNIVERSE. 



to the desired position, as a current of water 

 may be conveyed in a tube, or a stream by its 

 banks; while insulation serves to keep the 

 electric current substantially confined to the 

 line of the conductor. 



A current of water will meet a resistance in 

 the shape of a water-wheel and cause it to 

 revolve, and that in turn will communicate 

 motion to machinery; while a current of elec- 

 tricity will revolve the armature of a motor, 

 which in turn will move vehicles and machin- 

 ery that resist this movement. 



The current of water and the electric cur- 

 rent are alike continuous if the supply is con- 

 tinuous. Both can be divided, and made to 

 perform various service at the same time; and 

 when they are both comprehended there will 

 be no more mystery about the one than the 

 other. 



The distinction between the term static and 

 dynamic, when applied to this motion, seems 

 to signify in the former, nothing more than 

 the circumstance that a current is restrained 



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