SCIENCE IN THE INDUSTRIAL WORLD 



wires as the return circuit of two batteries. The fact that 

 the earth could be made to perform the same function, 

 however, was not discovered until many years later. 



In experimenting with land electricity in 1837, 

 Steinheil, in England, made the accidental discovery 

 that the earth could be made to take the place of the 

 return wire of his telegraph. It had occurred to Steinheil 

 that the two rails of the railroad track could be utilized 

 for sending telegraphic messages in place of two wires. 

 He therefore connected the wires from the telegraphic 

 instrument with the rails of the track, arranging a 

 similar instrument at the station a few miles distant. 

 He found, however, that messages could not be trans- 

 mitted in this manner, and in investigating to determine 

 the cause of this failure, he discovered that the current, 

 instead of passing along one rail and returning by the 

 other, made a short cut through the earth from rail to 

 rail. This suggested the possibility of utilizing the earth 

 itself as a conducting medium for wireless telegraphy, 

 although experiments in this direction were without 

 results for many years. 



WATER AND EARTH AS CONDUCTORS 



About five years later, in 1842, Samuel Morse suc- 

 ceeded in sending wireless messages, first across a canal 

 and then across a river something like a mile in width. 

 He did this by immersing the ends of two telegraph 

 wires running parallel along the opposite banks for 

 some distance, the four ends of these wires being im- 

 mersed at points in the river at which the wires would 



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