the mains or parallel lines
of a circuit which does not go through the
apparatus for which the circuit is intended.

Coherer. A tube, or other structure, containing normally
high resistance particles which form a path or bridge
between the opposite terminals of a circuit.

Coil. A wire, usually insulated, wound around a spool.

Coil, Induction. One of a pair of coils designed to change the
voltage of a current of electricity, from a higher
to a lower, or from a lower to a higher
electro-motive force.

Coil, Resistance. A coil so wound that it will offer a resistance
to a steady current, or reduce the flow of electricity.

Commutator. A cylinder on the end of the armature of a dynamo
or motor and provided with a pair of contact plates
for each particular coil in the armature, in order
to change the direction of the current.

Compass. An apparatus which indicates the direction or flow
of the earth's magnetism.

Condenser. A device for storing up electro-static charges.

Conductance. That quality of a conductor to carry a current of
electricity, dependent on its shape for the best
results.

Conduction. The transmission of a current through a rod, wire
or conductor.

Conductivity. That quality which has reference to the capacity
to conduct a current.

Conductor. Any body, such as a bar, rod, wire, or machine,
which will carry a current.

Connector. A binding post, clamp, screw, or other means to
hold the end of a wire, or electric conductor.

Contact. To unite any parts in an electric circuit.

Controller. The handle of a switchboard, or other contact
making and breaking means in a circuit.

Converter. An induction coil in an alternating circuit for
changing potential difference, such as high
alternating voltage into low direct current voltage.

Convolution. To wind like a clock spring.

Core. The inner portion of an electro-magnet. The inside
part of an armature