xJO 



If a (horse is stood beside the fence, instead of the lightning jumping the air-gap 

 from the wire to the ground it strikes the horse. (Fig. 30.) 



If, however, the fence-wire is connected with the ground by means of a ground- 

 wire the horse is perfectly safe. (Fig. 31.) 



Moreover, if the ground-wire be let project above the fence, ending in a sharp 

 point, no flash will occur. (Fig. 32.) The charge is neutralized by leaking ofF 

 the point. 



Fig. 28. — Metallic roof grounded, and with 

 notched metallic ridge. No stroke can be 

 produced. Ordinary lightning rod points 

 would be as effective, and probably more dur- 

 able. 



Fig. 29. — Lightning strikes a fence 

 jumps air-gap to earth. 



and 



Fig. 30. — A horse standing by the fence, 

 however, forms an easier path, and the 

 horse is struck. Note flash from fence to 

 horse's nose. 



Fig. 31. — If, however, the fence wires are 

 grounded, the flash follows the ground wire 

 and the horse is safe. 



Consequently, wire fences should be grounded, and the ground-wire projected 

 above the fence if the stock is to be protected in the best possible way. 



It is hard to conceive how any person could follow these experiments and 

 phenomena and doubt the value of lightning rods. We have seen that by means 

 of rods on these little toys we can either carry ofT a stroke without damage or we 

 can prevent a stroke nltcrotbor. TTonfo. if in ro'ldin'i onr l)uililino-s we observe the 



