proximity to it.

Galvanoscope. An instrument, like a galvanometer, which determines
whether or not a current is present in a tested wire.

Generator. A term used to generally indicate any device which
originates a current.

German Silver. An alloy of copper, nickel and zinc.

Graphite. One form of carbon. It is made artificially by the
electric current.

Grid. The metallic frame of a plate used to hold the active
material of an accumulator.

Gravity. The attraction of mass for mass. Weight. The
accelerating tendency of material to move toward the
earth.

Gutta Percha. Caoutchouc, which has been treated with sulphur,
to harden it. It is produced from the sap of
tropical trees, and is a good insulator.

Harmonic Receiver. A vibrating reed acted on by an electro-magnet,
when tuned to its pitch.

High E. M. F. A term to indicate currents which have a high
voltage, and usually low amperage.

Igniter. Mechanism composed of a battery, induction coil and
a vibrator, for making a jump spark, to ignite gas,
powder, etc.

I. H. P. Abbreviation, which means Indicated Horse Power.

Impulse. A sudden motion of one body acting against another.
An electro-magnetic wave magnetizing soft iron,
and this iron attracting another piece of iron, as an
example.

Incandescence, A conductor heated up by a current so it will
Electric. glow.

Induced Current. A current of electricity which sets up lines of
force at right angles to the body of the wire
through which the current is transmitted.

Induction, Magnetic. A body within a magnetic field which is excited
by the magnetism.

Installation. Everything belonging to an equipment of a building,
or a circuiting system to do a certain thing.

Insulation. A material or substance which resists the passage
of a current placed around a conductor.

Intensity. The strength of a magnetic field, or of a current
flowing over a wire.

Internal Re