Action of magnets upon each other,32.Adjuster, for lamp cords,151.Air pressure, effect of spark upon,155.Aluminum-leaf, for electroscopes,5.Alternating current,129,130;system of wiring for,144.Amalgamation of zincs,47.Amber, electrification upon,3.Ammeter, the,74;how placed in circuit,77.Ampere, the,72.Annunciators,177.Anode,79,82.Apparatus for electrical measurements,Chap. VI.Appliances, for distribution of currents,141;for electric railways,167;for heating by electricity,147.Arc, the electric,152.Arc lamp, the,153;how light is produced by,Chap. XXII.;double carbon,153;hand-feed focussing,153;for search-lights,153;short, for basements,153;single carbon,153;for theater use,153.Armature, of dynamo,127,129;of electromagnets,98;of horseshoe magnet,26;of motors,161;uses of,39.Artificial magnets,25.Astatic, detectors,94;galvanometer,73;needles,94.Aurora borealis,23.Automatic, current interrupters,104,115;gas lighters,174;program clocks,172.Automobiles,169;controllers for,169;motors for,169;steering of,169;storage batteries for,169.Bamboo filaments,149.Bar magnets,27;magnetic figures of,38.Batteries, large plunge,54;plunge,53;secondary,86;storage, and how they work,Chap. IX.Bell, the electric, and some of its uses,Chap. XV.;electric,116;magneto testing,117;trembling, etc.,116.Bell transmitter,120.Belts, electricity generated by friction upon,1.Benjamin Franklin,18.Bichromate of potash cells,51, etc.Binding-posts,Chap. V.;common forms of,63.Blasting, by electricity,147;electric machines for,147.Bluestone cell,56.Boats, electric,168.Boilers, use of in central stations,170.Bones, photographed by x-rays,Chap. XXIII.Boosters,136.Brushes,129.Bunsen cells,56a.Burner, automatic,174;for gas-lights,174;ratchet,174.Buzzers, electric,118.Cables and wires,143.Call boxes, electric,173.Carbon, in arc lamps,152,153;filament,149;transmitter,123.Carpet, electricity generated upon,1.Cars, electric,164;controllers for,165;heating by electricity,167;overhead system for,166;underground system for,166.Cat, electricity generated upon,1.Cathode, definition of,79;rays,157.Cells, Bunsen,56a;bichromate of potash,51;closed circuit,50;dry,58;Edison-Lelande,59;electricity generated by,Chap. III.;Fuller,55;Gonda,57;gravity,56;Grenet,52;Leclanché,57;open circuit,50;plates and poles of,45a;polarization of,48;simple,45,49;single-fluid,49;two-fluid,49;various voltaic,Chap. IV.Central stations,170;a word about,Chap. XXVI.Chain lightning,19.Chafing-dishes, electrical,147.Charging condensers,15.Chemical action, and electricity,81.Chemical effects of electric current,Chap. VII.Chemical meters,78.Church organs, pumped by motors,162.Circuits, electric,50;for lamps,144.Cleats, porcelain,141;wooden,141.Clocks, automatic electric,172.Closed circuit cells,50.Coils, induction, and how they work,Chap. XIII.;induction, construction of,104;method of joining,98;primary and secondary,103;resistance,69;rotation of,95;of transformers,135.Collectors on dynamos,129.Commutators,129.Compasses, magnetic,31.Compound, magnets,28;wound dynamo,131.Condensation of static electricity,15.Condensers,15;for induction coils,104.Conductors, and insulators,4,138.Conduits, electric,140.Connections, electrical,60;for telegraph lines,111.Controllers, for automobiles,169;for electric cars,165.Copper sulphate, effects of current on,82;formula of,79.Copper voltameters,75.Cords, adjustable for lamps,151.Coulomb, the,76.Crater of hot carbons,152.Crookes tubes,156,158.Current, detectors,93;direction of in cell,46;from magnet and coil,100;from two coils,102;induced,127;of induction coils,105;interrupters, automatic,104,115;local,47;primary and secondary,102;transformation of,Chap. XVIII.;transmission of,134.Currents, and motion,160;how distributed for use,Chap. XIX.Current strength,71;measurement of,73;unit of,72.Cylinder electric machines,9.Daniell cell,56.D'Arsonval galvanometer,73.Declination,41.Decorative incandescent lamps,151.Dental, lamps,151;outfits,176.Detectors, astatic,94;current,93.Diamagnetic bodies,29.Diaphragm for telephones,120.Dip, of magnetic needle,42.Direct current,129,130.Direction of current in cell,46.Discharging condensers,15.Disruptive discharges,154.Distribution of currents for use,Chap. XIX.Door opener, electric,175.Dots and dashes,110.Drill press, run by motor,162.Dry cells,58.Dynamo, the,126;alternating current,130;commutator of,129;compound wound,131;direct current,130;lamps connected to,132;series wound,131;shunt wound,131;used as motor,161;use of in central stations,170;used with water power,170.Dynamos, electricity generated by,Chap. XVII.;types of,130;various machines,132;winding of,131.Dynamotors,137.Earth, inductive influence of,43;lines of force about,40,42.Ebonite, electricity by friction upon,3,4.Edison-Lelande cells,59.Electric, automobiles,169;bell, and some of its uses,Chap. XV.;boats,168;buzzers,118;cars,164;conduits,140;fans,162;flat-irons,146;gas lighters,174;griddles,147;kitchen,147;lights, arc,Chap. XXII.;lights, incandescent,Chap. XXI.;machines, static,7to 13;machines, uses of,14;motor, the,161;motor, and how it does work,Chap. XXIV.;soldering irons,146;telegraph, and how it sends messages,Chap. XIV.;telephone, and how it transmits speech,Chap. XVI.;welding,146.Electric current, and work,133;and chemical action,81;chemical effects of,Chap. VII.;how distributed for use,Chap. XIX.;magnetic effects of,Chap. XI.;how transformed,Chap. XVIII.Electrical, connections,60;horse-power,77;measurements,Chap. VI.;resistance,68;resistance, unit of,69;units,Chap. VI.Electricity, about frictional,Chap. I.;and chemical action,81;atmospheric,18;heat produced by,Chap. XX.;history of,3;how generated upon cat,1;how generated by dynamos,Chap. XVII.;how generated by heat,Chap. X.;how generated by induction,Chap. XII.;how generated by voltaic cell,Chap. III.;origin of name,2.Electrification, kinds of,6;laws of,7.Electrolysis,79.Electrolyte,79.Electromagnetic induction,99.Electromagnetism,91.Electromagnets,96;forms of,97.Electro-mechanical gong,116.Electromotive force, defined,65,71;measurement of,67;of polarization,85;of static electricity,17;unit of,66.Electrophorus, the,8.Electroplating,82.Electroscopes,5.Electrotyping,83.Experiments, early, with currents,44;some simple,1.External resistance,68.Fan motors,162.Field, magnetic,37.Field-magnets,129.Figures, magnetic,38.Filaments, carbon,149;bamboo, etc.,149.Fire, St. Elmo's,22.Flat-irons, electric,147.Floor mains,139.Fluoroscope,158.Force, and induced currents,101;lines of magnetic,38;lines of about a wire,92,96;lines of about a magnet,37,38.Frictional electricity, about,Chap. I.;location of charge of,4;sparks from,4.Fuller cell, the,55.Fuse, link,142;plug,142;ribbons,142;wire,142.Fusible rosettes,142.Galvani, early experiments of,44.Galvanometers,73;astatic,73;considered as motor,161;D'Arsonval,73;tangent,73.Galvanoscope,73;astatic,94.Gas lighters, electric,174.Geissler tubes,156.Generators, electric,126.Glass, electricity generated upon,4.Glue pots, electric,147.Gold-leaf, for electroscopes,5.Gold plating,82.Gonda cell,57.Gong, electro-mechanical,116.Gravity cell, the,56;replaced by dynamotors,137.Grenet cell,52.Griddles, electric,147.Guard, for lamps,151.Heat, how generated by electricity,Chap. X.;and magnetism,35;and resistance,145.Heat lightning,19.Heaters, for cars,167.History of electricity,3.Horse-power, electrical,77.Horseshoe, permanent magnets,26;electromagnets,97,98.Human body, bones of, photographed by x-rays,Chap. XXIII.Hydrogen, action of in cell,48;attraction of for oxygen,85.Incandescence,148.Incandescent lamp,149;candle-power of,150;current for,150;light produced by,Chap. XXI.;construction of,149;uses of,151.Inclination of magnetic needle,42.Indicating push-button,61.Induced currents,127;and lines of force,101;by rotary motion,128;of induction coils,105;of transformers,135.Induced magnetism,36.Induction, electricity generated by,Chap. XII.;electromagnetic,99.Induction coils, condensers for,104;construction of,104;currents of,105;how they work,Chap. XIII.;in telephone work,124;uses of,106.Inductive influence of earth,43.Influence machines for medical purposes,13.Ink writing registers,114.Insulating tubing,141.Insulators,141;and conductors,4,138;feeder-wire,167;for poles,167;porcelain,141.Internal resistance,68.Interrupters, automatic current,104,115.Ions,80.Iron, electricity upon, by friction,4.Jar, Leyden,15.Jarring magnets, effects of,33.Keeper of magnets,26.Keys, telegraph,109.Kinds of electrification,6.Kitchen, electric,147.Knife switch,62.Lamp, incandescent, candle-power of,150;cord, adjustable,151;current for,150;dental,151;for desks,151;for throat,151;guard for,151;incandescent,149;socket,151;with half shade,151.Lamp, the arc,153;how light is produced by,Chap. XXII.;double carbon,153;hand-feed focussing,153;for search-lights,153;