JOIXT DEVELOPMENT AND NOISE FREQUENCY INDUCTION 205 



pleted and its efforts discontinued. This cooperative work must 

 always bear a relation to the total development efforts of both the 

 power and communication fields. As has already been pointed out, 

 this work is concerned with two electrical arts which have been particu- 

 larly noteworthy for their success in constantly developing their tech- 

 nical methods and expanding their services. These developments will 

 surely continue and constant consideration of the physical problems of 

 coordination is needed to insure that such developments act to steadily 

 improve rather than to make more difficult the coordination of power 

 and communication circuits. 



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