ClipArt ETC
An illustration of an electric bell. "The magnetizing coils are a a, and they are connected with their terminals at binding posts b1, b2. When these binding posts are connected with the electric current and the circuit is closed, the armature, at d, will be attracted, and will push the hammer e upon the bell. When the armature is attracted, the spring f leaves the screw contact g, against which it rests." -Foster, 1921

Electric Bell

An illustration of an electric bell. "The magnetizing coils are a a, and they are connected with their…