15 



Franklik Proves That Lightning is Electricity. 



The electrical machine was discovered in 16-iO, but it took one hundred years 

 to perfect it and produce the large sparks, and to learn the fundamental principles 

 of electricity. In 1751 Benjamin Franklin, observing the similarity between the 

 lightning flash and the sparks that could be produced by an electrical machine, came 

 to the conclusion that lightning was nothing else than a discharge of electricity, or 

 rather the light produced by such discharge. To prove this, he sent a kite up into 

 the clouds as a thunderstorm was approaching. The string which held the kite 

 was connected with an electric key in the laboratory. As soon as the string became 

 wet electric sparks occurred at the key, which were in every respect like those pro- 

 duced with the electrical machine. Franklin's reasoning then ran something as 

 follows : If lightning is produced by a discharge of electricity, then it must obey 

 the laws of electricity. Hence, it should be possible to prevent lightning in many 

 cases, just as an electric spark can be prevented in this machine by having a pointed 



Fig. 17. — Candle-flame held between points 

 of electrical machine. When the machine 

 is not turned, i.e., when there is no charge, 

 the flame burns straight up and sharp in 

 outline. 



Fig. 18. — But when the machine is 

 turned the candle-flame is blown side- 

 wise. If the candle is held up level with 

 the point the flame is hlown out. The 

 wind shows that electricity is leaking off 

 the point. 



wire attached to each side, or if a flash does occur, it should be possible to conduct 

 the current to the earth by wire without injury to the building bearing the wire. 

 In other words : If lightning is produced by a discharge of electricity, lightning 

 rods must be a practical possibility. 



After Franklin's results were published lightning rods began to be installed 

 on farm buildings through the United States, and later in Canada, but in the early 

 stages lightning rod companies knew very little of the laws of electricity, conse- 

 quently were unable to instruct their men as to how buildings should be rodded, and, 

 hence, in some cases', the rods did not produce the protection they were expected 

 to. Besides, numerous swindles in connection with lightning rods were worked 

 off on the farmers, so that in time lightning rods came into great disrepute. How- 

 ever, Sir Wm. Snow Harris, in England, devised a system of lightning protectors 

 for ships, which completely did awav with the one-time tremendous loss caused by 

 lightning to the ships of the British Navy. So effective was his system that the 

 late Queen A^ictoria bestowed a kni^dithood nnd an annuity upon him in recognition 



