Part 14 (2/2)

Amber. A resin, yellow in color, which when rubbed with a cloth, becomes excited and gives forth negative electricity.

Ammeter. An instrument for measuring the quant.i.ty 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 s.p.a.ce 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 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 acc.u.mulates 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 a.s.sembled 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.

<script>