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OUR PHYSICAL WORLD 



only partly between those of the other set. By adjusting the 

 plates, the capacity can be varied and the natural vibration 

 frequency of the primary circuit can be changed. This type of 



FIG. 120. Diagram of a more elaborate receiving set 



outfit permits much closer tuning than the outfit shown in Figure 

 119, and since the coupling is adjustable, more interference can 

 be cut out. 



Many large commercial wireless telegraph stations and ship 

 stations still employ the same method of transmission of signals 



