ELECTRICITY 73 



passage of electricity. And why do I put that paper tassel 

 (FiG. 43) at the top of the pole, upon a glass rod, and con- 

 nect it with this machine by means of a wire? You see at 

 once that as soon as the handle 

 of the machine is turned, the 

 electricity which is evolved 

 travels along this wire and up 

 the wooden rod, and goes to 

 the tassel at the top, and you 

 see the power of repulsion with 

 which it has endowed these 

 strips of paper, each spreading 

 outward to the ceiling and sides 

 of the room. The outside of 

 that wire is covered with gutta- 

 percha; it would not serve to 

 keep the force from you when 

 touching it with your hands, 

 because it would burst through; 

 but it answers our purpose for 

 the present. And so you per- 

 ceive how easily I can manage 

 to send this power of electricity 

 from place to place by choosing 

 the materials which can conduct 

 the power. Suppose I want to 

 fire a portion of gunpowder, I 

 can readily do it by this trans- 

 ferable power of electricity. I 



will take a Ley den jar, or any other arrangement which 

 gives us this power, and arrange wires so that they may 

 carry the power to the place I wish ; and then placing a little 

 gunpowder on the extremities of the wires, the moment I 

 make the connection by this discharging rod I shall fire 

 the gunpowder [the connection was made and the gun- 

 powder ignited]. And if I were to show you a stool like 

 this, and were to explain to you its construction, you 

 could easily understand that we use glass legs because 

 these are capable of preventing the electricity from going 

 away to the earth. If, therefore, I were to stand on 



