In the diagrams of lighting circuits in the following pages, the symbols given below will be used. See Fig. 14.

Symbol a is a safety plug, or cut-out.

Symbol b is a wall switch.

Symbol c is a 32-candlepower lamp.

Symbol d is a dynamo.

Symbol e is a 16-candlepower lamp.

Symbol f is a 16-candlepower lamp with a key socket

Symbol g is a 2-arm bracket with key sockets.

Symbol h is a 3-light chandelier with key sockets. Symbol i is a 10-candlepower lamp.

Fig. 14.