| Acid. | Accumulator material is sulphuric acid, diluted with
water. |
| Active Material. | That part of the material in accumulator plates
which is acted upon by the electric current. |
| Accumulator. | A cell, generally known as a storage battery, which
while it initially receives a charge of electricity, is
nevertheless, of such a character, owing to the
active material of which it is made, that it accumulates,
or, as it were, generates electricity. |
| Aerial Wire, or Conductor. | The wire which, in wireless telegraphy, is carried up
into the air to connect the antennæ with the receiving and sending apparatus. |
| Alarm, Burglar. | A circulating system in a building, connected up
with a bell or other signaling means. |
| Alloy. | A mixture of two or more metals; as copper and
zinc to make brass; nickel and zinc to form German silver. |
| Alternating Current. | A current which goes back and forth in opposite directions,
unlike a direct current which flows continuously
in one direction over a wire. |
| Alternation. | The term applied to a change in the direction of an
alternating current, the frequency of the alternations
ranging up to 20,000 or more vibrations
per second. |
| Amber. | A resin, yellow in color, which when rubbed with a
cloth, becomes excited and gives forth negative
[p. 190]electricity. |
| Ammeter. | An instrument for measuring the quantity or flow of
electricity. |
| Ampere. | The unit of current; the term in which strength of
the current is measured. An ampere is an electromotive
force of one volt through a resistance of one ohm. |
| Annunciator. | A device which indicates or signals a call given
from some distant point. |
| Anode. | The positive terminal in a conducting circuit, like
the terminal of the carbon plate in a battery. It
is a plate in an electroplating bath from which
the current goes over to the cathode or negative
plate or terminal. |
| Arc. | A term employed to designate the gap, or the current
which flows across between the conductors,
like the space between the two carbons of an arc
lamp, which gives the light. |
| Armature. | A body of iron, or other suitable metal, which is in
the magnetic field of a magnet. |
| Armature Bar. | The piece which holds the armature. Also one of a
series of bars which form the conductors in armature
windings. |
| Armature Coil. | The winding around an armature, or around the core
of an armature. |
| Armature Core. | The part in a dynamo or motor which revolves, and
on which the wire coils are wound. |
| Astatic (Galvanometer). | That which has no magnetic action to direct or divert
anything exterior to it. |
| Atom. | The ultimate particle of an elementary substance. |
| Attraction. | That property of matter which causes particles to
adhere, or cohere, to each other. It is known
[p. 191]under a variety of terms, such as gravitation, chemical
affinity, electro-magnetism and dynamic attraction. |
| Automatic Cut-out. | A device which acts through the operation of the
mechanism with which it is connected. It is usually
applied to a device which cuts out a current
when it overcharges or overloads the wire. |
| Bath. | In electroplating, the vessel or tank which holds the
electroplating solution. |
| Battery. | A combination of two or more cells. |
| Battery, Dry. | A primary battery in which the electrolyte is made
in a solid form. |
| Battery, Galvanic. | A battery which is better known by the name of the
Voltaic Pile, made up of zinc and copper plates
which alternate, and with a layer of acidulated paper
between each pair of plates. |
| Battery, Storage. | A battery which accumulates electricity generated by
a primary battery or a generator. |
| Brush. | A term applied to the conducting medium that bears
against the cylindrical surface of a commutator. |
| Buzzer. | An electric call produced by a rapidly moving armature
of an electro-magnet. |
| Cable. | A number of wires or conductors assembled in one
strand. |
| Candle-power. | The amount of light given by the legal-standard candle.
This standard is a sperm candle, which burns
two grains a minute. |
| Capacity. | The carrying power of a wire or circuit, without
heating. When heated there is an overload, or the
capacity of the wire is overtaxed. |
| Capacity, Storage. | The quantity of electricity in a secondary battery
when fully charged, usually reckoned in ampere
[p. 192]hours. |
| Carbon. | A material, like coke, ground or crushed, and formed
into sticks or plates by molding or compression.
It requires a high heat to melt or burn, and is used
as electrodes for arc lamps and for battery elements.
It has poor conductivity, and for arc lamps
is coated with copper to increase its conductivity. |
| Cell, Electrolytic. | A vessel containing an electrolyte for electroplating
purposes. |
| Charge. | The quantity of electricity on the surface of a body
or conductor. |
| Chemical Change. | When a current passes through electrodes in a solution,
a change takes place which is chemical in
its character. Adding sulphuric acid to water produces
heat. If electrodes of opposite polarity are
placed in such an acid solution, a chemical change
is produced, which is transformed into electricity. |
| Choking Coil. | An instrument in a circuit which by a form of resistance
regulates the flow of the current, or returns
part of it to the source of its generation. |
| Counter-electromotive Force. | Cells which are inserted in opposition to a battery
to reduce high voltage. |
| Circuit, Astatic. | A circuit in an instrument so wound that the earth's
magnetism will not affect it. |
| Circuit Breaker. | Any instrument in a circuit which cuts out or interrupts
the flow of a current. |
| Circuit, External. | A current flows through a wire or conductor, and
also along the air outside of the conductor, the
latter being the external circuit. |
| Circuit Indicator. | An instrument, like a galvanometer, that shows the
direction in which a current is flowing through a
[p. 193]conductor. |
| Circuit, Return. | Usually the ground return, or the negative wire from
a battery. |
| Circuit, Short. | Any connection between 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
[p. 194]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 wound with wire. |
| Core, Laminated. | When the core is built up of a number of separate
pieces of the same material, but not insulated from
each other. |
| Coulomb. | The unit of electrical quantity. It is the quantity
passed by a current of one ampere intensity in
one second of time. |
| Couple, Electric. | Two or more electrodes in a liquid to produce an
electric force. |
| Current, Alternating. | A natural current produced by the action of electro-magnets.
It is a succession of short impulses in
opposite directions. |
| Current, Constant. | A current which is uniformly maintained in a steady
stream. |
| Current, Induced. | A current produced by electro-dynamic induction. |
| Current Meter. | An apparatus for indicating the strength of a current.
An ammeter. |
| Current, Oscillating. | A current which periodically alternates. |
| Current, Periodic. | A periodically varying current strength. |
| Current, Undulating. | A current which has a constant direction, but has a
[p. 195]continuously varying strength. |
| Decomposition. | The separation of a liquid, such as an electrolyte,
into its prime elements, either electrically or otherwise. |
| Deflection. | The change of movement of a magnetic needle out of
its regular direction of movement. |
| Demagnetization. | When a current passes through a coil wound on an
iron core, the core becomes magnetized. When the
current ceases the core is no longer a magnet. It
is then said to be demagnetized. It also has reference
to the process for making a watch non-magnetic
so that it will not be affected when in
a magnetic field. |
| Density. | The quantity of an electric charge in a conductor
or substance. |
| Depolarization. | The removal of magnetism from a permanent magnet,
or a horse-shoe magnet, for instance. It is
generally accomplished by applying heat. |
| Deposition, Electrolysis. | The act of carrying metal from one pole of a cell
to another pole, as in electroplating. |
| Detector. | Mechanism for indicating the presence of a current
in a circuit. |
| Diaphragm. | A plate in a telephone, which, in the receiver, is
in the magnetic field of a magnet, and in a transmitter
carries the light contact points. |
| Dielectric. | A non-conductor for an electric current, but through
which electro-static induction will take place. For
example: glass and rubber are dielectrics. |
| Discharge. | The current flowing from an accumulator. |
| Disintegration. | The breaking up of the plate or active material. |
| Disruptive. | A static discharge passing through a dielectric. |
| Duplex Wire. | A pair of wires usually twisted together and insulated
from each other to form the conducting
[p. 196]circuit of a system. |
| Dynamic Electricity. | The term applied to a current flowing through a
wire. |
| Dynamo. | An apparatus, consisting of core and field magnets,
which, when the core is turned, will develop a
current of electricity. |
| Earth Returns. | Instead of using two wires to carry a circuit, the
earth is used for what is called the return circuit. |
| Efficiency. | The total electrical energy produced, in which that
wasted, as well as that used, is calculated. |
| Elasticity. | That property of any matter which, after a stress,
will cause the substance to return to its original
form or condition. Electricity has elasticity, which
is utilized in condensers, as an instance. |
| Electricity, Atmospheric. | Lightning, and, in short, any current or electrical
impulse, like wireless telegraphic waves, is called
atmospheric. |
| Electricity, Voltaic. | Electricity with a low potentiality and large current
density. |
| Electrification. | The process of imparting a charge of electricity to
any body. |
| Electro-chemistry. | The study of which treats of electric and chemical
forces, such as electric plating, electric fusing,
electrolysis, and the like. |
| Electrode. | The terminals of a battery, or of any circuit; as, for
instance, an arc light. |
| Electrolyte. | Any material which is capable of being decomposed by
an electric current. |
| Electro-magnetism. | Magnetism which is created by an electric current. |
| Electrometer. | An instrument for measuring static electricity, differing
from a galvanometer, which measures a current
in a wire that acts on the magnetic needle
[p. 197]of the galvanometer. |
| Electro-motive Force. | (E. M. F.) Voltage, which is the measure or unit
of e. m. f. |
| Electroscope. | A device for indicating not only the presence of
electricity, but whether it is positive or negative. |
| Electro-static Accumulator. | Surfaces separated by a dielectric for opposite charging
of the surface. |
| Element. | In electricity a form of matter, as, for instance, gold,
or silver, that has no other matter or compound.
Original elements cannot be separated, because
they are not made up of two or more elements,
like brass, for instance. |
| Excessive Charge. | A storage battery charged at too high a rate. |
| Excessive Discharge. | A storage battery discharged at too high a rate. |
| Excessive Overcharge. | Charging for too long a time. |
| Exciter. | A generator, either a dynamo or a battery, for exciting
the field of a dynamo. |
| Exhaustive Discharge. | An excessive over-discharge of an accumulator. |
| F. | The sign used to indicate the heat term Fahrenheit. |
| Fall of Voltage. | The difference between the initial and the final voltage
in a current. |
| Field. | The space or region near a magnet or charged wire.
Also the electro-magnets in a dynamo or motor. |
| Flow. | The volume of a current going through a conductor. |
| Force, Electro-magnetic. | The pull developed by an electro-magnet. |
| Frictional Electricity. | A current produced by rubbing dissimilar substances
together. |
| Full Load. | The greatest load a battery, accumulator or dynamo
[p. 198]will sustain. |
| Galvanic. | Pertaining to the electro-chemical relations of metals
toward each other. |
| Galvanizing. | The art of coating one metal with another, such, for
instance, as immersing iron in molten zinc. |
| Galvanometry. | An instrument having a permanently magnetized
needle, which is influenced by a coil or a wire in
close 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.
[p. 199]An electro-magnetic wave magnetizing soft iron,
and this iron attracting another piece of iron, as an example. |
| Incandescence, Electric. | A conductor heated up by a current so it will 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 Resistance. | The current strength of electricity of a wire to resist
the passage. |
| Interrupter. | A device in a wire or circuit for checking a current.
It also refers to the vibrator of an induction coil. |
| Joint. | The place where two or more conductors are united. |
| Joint Resistance. | The combined resistance offered by two or more substances
or conductors. |
| Jump Spark. | A spark, disruptive in its character, between two
conducting points. |
| Initial Charge. | The charge required to start a battery. |
| Kathode, or Cathode. | The negative plate or side of a battery. The plate
on which the electro deposit is made. |
| Key. | The arm of a telegraph sounder. A bar with a finger
piece, which is hinged and so arranged that it will
make and break contacts in an electric circuit. |
| Keyboard. | A switch-board; a board on which is mounted a number
[p. 200]of switches. |
| Kilowatt. | A unit, representing 1,000 watts. An electric current
measure, usually expressed thus: K.W. |
| Kilowatt Hour. | The computation of work equal to the exertion of
one kilowatt in one hour. |
| Knife Switch. | A bar of a blade-like form, adapted to move down
between two fingers, and thus establish metallic
connections. |
| Laminated. | Made up of thin plates of the same material, laid
together, but not insulated from each other. |
| Lamp Arc. | A voltaic arc lamp, using carbon electrodes, with
mechanism for feeding the electrodes regularly. |
| Lamp, Incandescent. | A lamp with a filament heated up to a glow by the
action of an electric current. The filament is within
a vacuum in a glass globe. |
| Leak. | Loss of electrical energy through a fault in wiring,
or in using bare wires. |
| Load. | The ampere current delivered by a dynamo under certain
conditions. |
| Low Frequency. | A current in which the vibrations are of few alternations
per second. |
| Magnet. | A metallic substance which has power to attract iron
and steel. |
| Magnet Bar. | A straight piece of metal. |
| Magnet Coil. | A coil of wire, insulated, surrounding a core of iron,
to receive a current of electricity. |
| Magnet Core. | A bar of iron adapted to receive a winding of wire. |
| Magnet, Field. | A magnet in a dynamo. A motor to produce electric
energy. |
| Magnet, Permanent. | A short steel form, to hold magnetism for a long
time. |
| Magnetic Adherence. | The adherence of particles to the poles of a magnet.
[p. 201] |
| Magnetic Attraction and Repulsion. | That quality of a metal which draws metals. Also
the pulling action of unlike poles for each other,
and pushing away of like poles when brought together. |
| Magnetic Force. | The action exercised by a magnet of attracting or
repelling. |
| Magnetic Pole. | The earth has North and South magnetic poles. The
south pole of a magnetic needle is attracted so it
points to the north magnetic pole; and the north
pole of the needle is attracted to point to the
south magnetic pole. |
| Magneto-generator. | A permanent magnet and a revolving armature for
generating a current. |
| Maximum Voltage. | The final voltage after charging. |
| Molecule. | Invisible particles made up of two or more atoms of
different matter. An atom is a particle of one substance only. |
| Morse Sounder. | An electric instrument designed to make a clicking
sound, when the armature is drawn down by a
magnet. |
| Motor-dynamo. | A motor and a dynamo having their armatures connected
together, whereby the motor is driven by
the dynamo, so as to change the current into a
different voltage and amperage. |
| Motor-transformer. | A motor which delivers the current like a generator. |
| Needle. | A bar magnet horizontally poised on a vertical pivot
point, like the needle of a mariner's compass. |
| Negative Electricity. | Amber, when rubbed, produces negative electricity.
[p. 202]A battery has positive as well as negative electricity. |
| Negative Element. | That plate in the solution of a battery cell which is
not disintegrated. |
| Normal. | The usual, or ordinary. The average. In a current
the regular force required to do the work. |
| North Pole, Electric. | The term applied to the force located near the north
pole of the globe, to which a permanent magnet
will point if allowed to swing freely. |
| O. | Abbreviation for Ohm. |
| Ohm. | The unit of resistance. Equal to the resistance of a
column of mercury one square millimeter in cross
section, and 106.24 centimeters in length. |
| Ohm's Law. | It is expressed as follows:
The current strength is equal to the electro-motive
force divided by its resistance.
The electro-motive force is equal to the current
strength multiplied by the resistance.
The resistance is equal to the electro-motive
force divided by the current strength.
|
| Overload. | In a motor an excess of mechanical work which
causes the armature to turn too slowly and produces
heat. |
| Phase. | One complete oscillation. The special form of a wave
at any instant, or at any interval of time. |
| Plate, Condenser. | In a static machine it is usually a plate of glass and
revoluble. |
| Plate, Negative. | The plate in a battery, such as carbon, copper or
platinum, which is not attacked by the solution. |
| Plating, Electro-. | The method of coating one metal with another by
electrolysis. |
| Polarity. | The peculiarity, in a body, of arranging itself with
reference to magnetic influence. |
| Parallel. | When a number of cells are coupled so that their
[p. 203]similar poles are grouped together. That is to
say, as the carbon plates, for instance, are connected
with one terminal, and all the zinc plates
with the other terminal. |
| Polarization. | When the cell is deprived of its electro-motive force,
or any part of it, polarization is the result. It is
usually caused by coating of the plates. |
| Porosity. | Having small interstices or holes. |
| Positive Current. | One which deflects a needle to the left. |
| Positive Electricity. | Any current flowing from the active element, such as
zinc, in a battery. The negative electricity flows
from the carbon to the zinc. |
| Potential, Electric. | The power which performs work in a circuit. |
| Potential Energy. | That form of force, which, when liberated, does or
performs work. |
| Power Unit. | The volt-amperes or watt. |
| Primary. | The induction coil in induction machines, or in a
transformer. |
| Push Button. | A thumb piece which serves as a switch to close a
circuit while being pressed inwardly. |
| Quantity. | Such arrangement of electrical connections which
give off the largest amount of current. |
| Receiver. | An instrument in telephony and telegraphy which
receives or takes in the sound or impulses. |
| Relay. | The device which opens or closes a circuit so as to
admit a new current which is sent to a more distant
point. |
| Repulsion, Electric. | That tendency in bodies to repel each other when
similarly charged. |
| Resilience. | The springing back to its former condition or position.
[p. 204]Electricity has resilience. |
| Resistance. | The quality in all conductors to oppose the passage
of a current. |
| Resistance Coil. | A coil made up of wire which prevents the passage
of a current to a greater or less degree. |
| Resistance, Electrolytic. | The counter force in an electrolyte which seeks to
prevent a decomposing current to pass through it. |
| Resistance: Internal, External. | The opposing force to the movement of a current
which is in the cell or generator. This is called
the internal. That opposite action outside of the
cell or generator is the external. |
| Resonator, Electric. | An open-circuited conductor for electrically resounding
or giving back a vibration, usually exhibited
by means of a spark. |
| Rheostat. | A device which has an adjustable resistance, so arranged
that while adjusting the same the circuit
will not be open. |
| Safety Fuse. | A piece of fusible metal of such resistance that it
breaks down at a certain current strength. |
| Saturated. | When a liquid has taken up a soluble material to the
fullest extent it is then completely saturated. |
| Secondary. | One of the two coils in a transformer, or induction
coil. |
| Secondary Plates. | The brown or deep red plates in a storage battery
when charged. |
| Self-excited. | Producing electricity by its own current. |
| Series. | Arranged in regular order. From one to the other
directly. If lamps, for instance, should be arranged
in circuit on a single wire, they would be
in series. |
| Series, Multiple. | When lamps are grouped in sets in parallel, and
[p. 205]these sets are then connected up in series. |
| Series Windings. | A generator or motor wound in such a manner that
one of the commutator brush connections is joined
to the field magnet winding, and the other end
of the magnet winding joined to the outer circuit. |
| Shunt. | Going around. |
| Shunt Winding. | A dynamo in which the field winding is parallel
with the winding of the armature. |
| Snap Switch. | A switch so arranged that it will quickly make a
break. |
| Sounder. | The apparatus at one end of a line actuated by a key
at the other end of the line. |
| Spark Coil. | A coil, to make a spark from a low electro-motive
force. |
| Spark, Electric. | The flash caused by drawing apart the ends of a conductor. |
| Specific Gravity. | The weight or density of a body. |
| Static Electricity. | Generated by friction. Also lightning. Any current
generated by a high electro-motive force. |
| Strength of Current. | The quantity of electricity in a circuit. |
| Synchronize. | Operating together; acting in unison. |
| Terminal. | The end of any electric circuit or of a body or machine
which has a current passing through it. |
| Thermostat, Electric. | An electric thermometer. Usually made with a metal
coil which expands through the action of the electricity
passing through it, and, in expanding, it
makes a contact and closes a circuit. |
| Transformer. | The induction coil with a high initial E. M. F. changes
into a low electro-motive force. |
| Unit. | A standard of light, heat, electricity, or of other
[p. 206]phenomena. |
| Vacuum. | A space from which all matter has been exhausted. |
| Vibrator. | Mechanism for making and breaking circuits in induction
coils or other apparatus. |
| Volt. | The unit of electro-motive force. |
| Voltage. | Electro-motive force which is expressed in volts. |
| Voltaic. | A term applied to electric currents and devices. |
| Volt-meter. | An apparatus for showing the difference of potential,
or E. M. F. in the term of volts. |
| Watt. | The unit of electrical activity. The product of amperes
multiplied by volts. |
| Watt Hour. | One watt maintained through one hour of time. |
| Waves, Electric Magnetic. | Waves in the ether caused by electro-magnetic disturbances. |
| X-rays. | The radiation of invisible rays of light, which penetrate
or pass through opaque substances. |
| Yoke, or Bar. | A soft iron body across the ends of a horseshoe magnet,
to enable the magnet to retain its magnetism
an indefinite time. |
| Zinc Battery. | A battery which uses zinc for one of its elements. |