THE WIRELESS TELEGRAPH 

 GEORGE ILES 



[From "Flame, Electricity and the Camera," copyright 

 by Doubleday, Page & Co., New York.] 



IN a series of experiments interesting enough 

 but barren of utility, the water of a canal, river, 

 or bay has often served as a conductor for the 

 telegraph. Among the electricians who have 

 thus impressed water into their service was 

 Professor Morse. In 1842 he sent a few signals 

 across the channel from Castle Garden, New 

 York, to Governor's Island, a distance of a mile. 

 With much better results, he sent messages, 

 later in the same year, from one side of the canal 

 at Washington to the other, a distance of eighty 

 feet, employing large copper plates at each ter- 

 minal. The enormous current required to over- 

 come the resistance of water has barred this 

 method from practical adoption. 



We pass, therefore, to electrical communica- 

 tion as effected by induction the influence which 

 one conductor exerts on another through an in- 

 tervening insulator. At the outset we shall do 

 well to bear in mind that magnetic phenomena, 

 which are so closely akin to electrical, are always 

 inductive. To observe a common example of 

 magnetic induction, we have only to move a 

 horseshoe magnet in the vicinity of a compass 

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