THE ELECTRIC LIGHT. 141 



burning in those cells, and that this is the light 

 of that burning [bringing the two poles in con- 

 tact and showing the electric light] ; and we 

 might so arrange our apparatus as to show that 

 the amounts of power evolved in either case 

 are identical. Having thus obtained power 

 over the chemical force, how wonderfully we are 

 able to convey it from place to place ! When 

 we use gunpowder for explosive purposes, we 

 can send into the mine chemical affinity by 

 means of this electricity ; not having provided 

 fire beforehand, we can send it in at the mo- 

 ment we require it. Now here (Jig. 47) is a 

 vessel containing two charcoal points, and I 

 bring it forward as an illustration of the won- 

 derful power of conveying this force from place 

 to place. I have merely to connect these by 

 means of wires to the opposite ends of the 

 battery, and bring the points in contact. See 

 what an exhibition of force we have ! We have 

 exhausted the air so that the charcoal cannot 

 burn, and therefore the light you see is really 

 the burning of the zinc in the cells behind me 

 there is no disappearance of the carbon, 

 although we have that glorious electric light ; 

 and the moment I cut off the connection it 



