EXTENSION OF THE TELEPHONE SYSTEM TO SHIPS 155 



any one of the four radio circuits. The cord circuits contain the 

 switching keys seen in front, by means of which the radio station 

 operator is enabled to split the circuit and talk either way, connect 

 the circuit thru and bridge on it and talk or monitor. This cord 



Fig. 8 



circuit is shown in Fig. 7 in relation to the rest of the wire-radio 

 junction circuit. It will be seen to be of a four-wire instead of the 

 more usual two-wire type and to comprise in reality two circuits, 

 one for east-bound and the other for west-bound transmission. This 



