Q. Describe how to connect up and use the boat-telephone.
A. 1o Connect one wire of the casemate 'phone to either side of the battery, and the other to the ground (waterpipe is a good ground).
2o The same end of the battery is connected to wire Nos. 1, 13, or 19 of the multiple cable leading to the distribution-box boat.
3o Connect one wire of the 'phone in the D. B. boat to this same core (No. 19, for example).
4o Connect the other wire to an earth plate which is overboard. (An earth plate is usually made of iron or copper.)
5o The other terminal of the telephone battery has a permanent connection to earth. These connections then place the two telephones in parallel with the battery.
To call, press the push-button.
To talk, press the talking-switch.
Q. Point out and describe the parts of a wall-telephone composite artillery type.
A. See Fig. 108.
Q. Give the tests for telephones.
A. 1st. Bell is not rung by its own magneto.
Analysis:
1. Short circuit on line.
2. Mechanical trouble in the bell.
3. Short circuit in the phone.
4. Open circuit in the phone.
5. Magneto does not generate.