=Motor, Electric.= A machine or apparatus for converting electric energy into mechanical kinetic energy or power. The electrical energy is usually generated by a dynamo, and distributed on conductors to motors located at various points. Electric motors are of two types--the A-C., or alternating current, and the D-C., or direct current. =Motor-car, Electric.= A self-propelling car driven by stored electricity. =Motor-dynamo.= A motor driven by a dynamo whose armature is firmly attached or connected to that of the dynamo. It is used for modifying a current. If the dynamo generates an alternating current of high potential, the motor converts it into a direct current of lower voltage but increased amperage. =Motor-transformer.= A transformer which is operated by a motor. A dynamo-electric machine provided with two armature windings, one serving to receive current, as a motor, the other to deliver current, as a generator, to a secondary circuit. N =N.= An abbreviation for the north-seeking pole in a magnet. =Natural Magnet.= A loadstone. =Needle.= A term applied to a bar-magnet poised horizontally upon a vertical point. A magnetic needle, or the magnet in a mariner’s compass. =Negative.= Opposed to positive. =Negative Electricity.= The kind of electricity with which a piece of amber is charged by friction with flannel. In a galvanic battery or cell the surface of the zinc is charged with negative electricity. Negative electricity, according to the theory of some scientists, really means a deficiency of electricity. =Negative Electrode.= The same as Negative Element. =Negative Element.= The plate not dissolved by the solution in a voltaic cell; the one which is positively charged. The carbon, platinum, or copper plate or pole in a battery. =Negative Feeder.= The conductor which connects the negative mains with the negative poles of a generator. =Negative Plate.= (_See_ Plate, Negative.) =Negative Pole.= (_See_ Pole, Negative.) =Neutral Feeder.= The same as Neutral Wire. =Neutral Wire.= The central wire in a three-wire system. =Nickel-bath.= A bath for the electro-deposition of nickel. =Non-arcing Fuse.= A fuse-wire which is enclosed in a tube packed with asbestos or silk, and which does not produce an arc when it fuses or blows out. It is practically noiseless, save for a slight hissing sound, accompanied by a light puff of smoke, which escapes from a venthole in the side of the tube. =Non-conductor.= A material or substance offering very high resistance to the passage of the electric current. =Non-magnetic Steel.= Alloys of iron incapable of being magnetized. They are composed of iron and manganese, nickel, steel, etc. =Normal.= Regular. The average value of observed quantities. Normal current is a regular current without variations. The force of a current at which a system is intended to work. =Normal Voltage.= The same as Normal Current. =North Pole.= The north-seeking pole of a magnet.