ELECTRICITY. 505 



or in other words, he will be struck. Another individual 

 standing at the distance of only a few feet, but out of 

 such a series, will be safe. This subject has however 

 been more fully discussed in our Tract on the Weather. 



3. It produces no sensible effects when passing through 

 conductors. 



Its motion is instantaneous as was before shown, at 

 least it passes with inconceivable velocity, but it produces 

 no perceptible effects, when it passes through good con- 

 ductors. Let a large wire be held in the hand, one 

 end touching the knob connected with the inside of a 

 Leyden jar, and then let an assistant, by means of a dis- 

 charger, bring the other end into connexion with the 

 knob. The charge will immediately pass from the knob 

 through the discharger to the wire, and through the wire 

 as it lies in the hand to the outside of the jar. Now, 

 however attentively the performer may examine the wire, 

 at the instant of the passing of the discharge, no percep- 

 tible effect of any kind can be observed. There is no 

 motion, no heat, and no light, and the hand does not 

 feel the shock in the slightest degree. 



When, however, the accumulated fluid, on its passage 

 to its place of destination finds its progress interrupted, 

 it then produces its most marked and striking effects. 

 Some of these we shall now notice. The violence of the 

 effect is proportioned to the degree of interruption. The 

 air is a non-conductor. If it has, therefore, to pass 

 through the air at an interruption in its circuit, the most 

 striking of its effects are produced. This brings us then 

 to our fourth particular. 



4. ElcdricSl light. 



It is impossible to use tHfeleclric machine at all, with- 

 out perceiving that the fluid evolves light whenever it 

 passes through the air. The jar cannot be discharged 

 without producing this effect, for if one end of the dis- 

 charger is brought into contact with the outside, and the 

 other is made to approach the knob, before it touches it, 

 the fluid will dart across, exhibiting the bright light which 

 the fluid always produces when passing through the air. 



