THE MAGNETO TELEPHONE 



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first being a bridged, grounded circuit and the second a bridged, metallic circuit. In 

 this system, as will be seen from the figures, each instrument is on a separate leg from 

 the line to the ground or on a " bridge " between the two wires of a metallic circuit. 



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Fig. 90 Connecting bridging telephone on a grounded line 



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Fig. 91 Connecting bridging telephone on a metallic line 



The bells of bridged telephones are constantly in circuit and each instrument, 

 therefore, at all times forms a separate path for tooth talking and ringing currents to 

 the ground or the return wire. It will, therefore, be evident that with low-resistance 

 bell coils the line resistance between instruments, except on very short lines, might 



