The Study of Elementary Electricity and Magnetism by Experiment / Containing Two Hundred Experiments Performed with Simple, Home-made Apparatus

by Thomas M. St. John

No. 97. Bar magnet, about 4 in. long and 5/16 in. in diameter.

No. 98. Coil of insulated wire wound on a soft iron core, to act as a primary coil for induction experiments. This coil fits inside of the hollow coils (Nos. 89, 90).

No. 99. A printed degree-card for the galvanoscope (No. 58). This is printed on stiff cardboard, about 3 in. in diameter.

No. 100. A printed scale for the Wheatstone's bridge (No. 80). This is printed on stiff paper. The scale is 8 in. long, and is divided into 10 large divisions, each of which is subdivided into 10 parts, thus making 100 parts in all.

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INDEX.

Numbers refer to paragraphs. See Table of Contents for the various experiments.

• Abreast, arrangement of cells, [365].
• Accumulators. (See [storage cells].)
• Action, local, [273].
• Air, as insulator, [144], [a].
• Alternating currents, [443].
• Amalgamating, [257], [274].
• Amber, [107].
• Ammeter, [353].
• Ampere, the, [351], [357].
• Ampere's rule, [386].
• Annealing, [6].
• Annunciators, [471].
• Anode, [373], [378].
• Applications of electricity, [Chap. XXVII].
• Arc lamp, [485].
• Arrangement, of cells, [363] to [368].
• Armature, the, [11], [78], [476].
• Astatic needles, [251], [253], [254];
• galvanoscope, [252], [256].
• Atmospheric electricity, [Chap. XIII.], [217];
• causes of, [221].
• Attraction, mutual, [111];
• and repulsion, laws of magnetic, [29];
• electric, laws of, [121].
• Aurora borealis, [223].
• Batteries, [Chap. XV.];
• storage, [382].
• Bell, electric, [468].
• Bell telephone, [480].
• Bichromate cell, [289].
• Bound electrification, [162], [191].
• Breaking a magnet, [51].
• Bridge, Wheatstone's, [324] to [330].
• Brushes, [476].
• Buzzers, electric, [468].
• Cable, submarine, as condenser, [182].
• Capacity, inductive, [169];
• electrical, [176], [178].
• Carbon, transmitter, [482];
• electroscope, [114].
• Cathode, [373].
• Cell, galvanic, [Chap. XV.];
• arrangement of, [363], [364], [365], [368];
• chemical action in, [270], [271];
• direction of current in, [268];
• local action in, [273];
• open and closed circuit, [286];
• polarization of, [278];
• poles of, [269];
• simple, [275];
• secondary, [382];
• single-fluid, [275];
• two-fluid, [281], [285];
• various galvanic, [286] to [291].
• Charge, in condenser, [195];
• residual of condensers, [197].
• Charging conductors, [Chap. VIII].
• Chemical action, [369].
• Chemical effects of current, [Chap. XXI].
• Circuit, electric, [266];
• divided, [293];
• short, [295].
• Coercive force, [44], [46].
• Coils, [390];
• induction, [473], [474];
• method of joining, [408];
• polarity of, [392];
• resistance, [309];
• simple resistance, [310].
• Commutator, [476].
• Compass, [26];
• our, [32];
• needle, [243], [249].
• Compound magnets, [73].
• Condensation of electrification, [Chap. X.], [178].
• Condensers, [178];
• action of, [186], [191];
• induction coil, [181];
• submarine cables, [182].
• Conductive discharge, [149], [184].
• Conductors, [126], [129], [133];
• hollow and solid, [153];
• and insulators, relation between, [133];
• and non-conductors, [312].
• Connections, electrical, [226] to [230].
• Contact breaker, [Exp. 195];
• § [466].
• Convective discharge, [149].
• Copper sulphate solution, [283].
• Cores, of electromagnets, [397].
• Coulomb, the, [354].
• Current electricity, [Part III].
• Current, [144], [a], [264];
• detectors, [232], [239];
• direction of in cell, [268];
• direct and alternating, [443];
• extra, [444];
• interrupters, [466];
• primary and secondary, [441];
• measurement of, [352];
• reverser, [235], [237];
• strength of, [Chap. XX.], [350], [358], [362] to [365];
• unit of, [351].
• Daniell cell, [290].
• Declination, [84].
• Depolarizers, [280], [282].
• Detectors, current, [232], [239].
• Diamagnetic bodies, [15].
• Dielectric, [184], [191], [195].
• Dielectrics, [166].
• Dip, [86].
• Direct currents, [428], [443].
• Dischargers, [188].
• Discharges, kinds of, [149].
• Divided circuits, [293], [323].
• Dry cells, [288].
• Dynamo, [435], [476].
• Earth's magnetism, [83], [92], [93].
• Electric, bells, [468];
• chime, [193];
• circuit, [266], [Chap. XVI.];
• current, [144], [a], [264];
• density, [155];
• field, [156];
• horse-power, [355];
• lighting, [484];
• machines, static, [216];
• motor, [477];
• polarization, [159];
• resistance, [Chap. XVIII.];
• wind, [155].
• Electricity, static, [Part II.];
• Current, [Part III.];
• Applications of,[ Chap. XXVII.], [456];
• kinds of, [100];
• derivation of name, [107];
• Atmospheric,[ Chap. XIII.], [217].
• Electrification, [Chap. VI.], [103], [116], [132], [134];
• and heat, [104];
• condensation of, [Chap. X.];
• escape of, [155];
• free and bound, [162];
• induced, [Chap. IX.];
• kinds of, [120];
• of earth, [222];
• source of in cells, [265];
• theories about, [145];
• two kinds of, [120], [211].
• Electrics and non-electrics, [134].
• Electrified bodies, [102], [107].
• Electrodes, [269].
• Electromagnetism,[ Chap. XXII.], [383].
• Electromagnets, [Chap. XXIII.], [396];
• cores of, [397];
• horseshoe, [405].
• Electromotive force, [144],[ Chap. XVII.], [296], [300], [303];
• measurement of, [Exp. 140];
• of polarization, [373], [382];
• series, [301];
• unit of, [297].
• Electrophorus, [138];
• action of, [171], [172];
• our, [139].
• Electrolysis, [370].
• Electrolyte, [370].
• Electroplating, [376], [378].
• Electroscope, action of, [206], [208];
• carbon, [114];
• pith-ball, [200];
• our leaf, [201], [202].
• Electroscopes, [Chap. XI].
• Electrotyping, [379].
• Equator of magnet, [13].
• Equipotential points, [326].
• External resistance, [307], [368].
• Extra current, [444];
• [Exp. 199].
• Field, electric, [156];
• magnetic, [Chap. IV.], [62], [80];
• magnets, [476].
• Figures, magnetic, [64];
• permanent, [417].
• Force, [103];
• lines of magnetic, [64], [73], [80], [156];
• lines of electric, [156];
• lines of about a wire, [385].
• Franklin, Benjamin, [218].
• Free electrification, [162].
• Frictional electricity, [Part II].
• Fulminating panes, [180].
• Galvanic cells, [Chap. XV.], [265];
• chemical action in, [270];
• various kinds of, [286] to [291].
• Galvanoscope, [240] to [249].
• Glass, as insulator, [136].
• Gold-leaf electroscope, [200], [209].
• Gravity cell, [291].
• Hardening steel, [8], [10].
• Heat, effect on resistance, [343];
• effect on magnet, [49].
• Horse-power, electric, [355].
• Horseshoe magnet, [11];
• advantages of, [82];
• electromagnets, [405].
• Hydrogen, [260], [262], [271], [278], [279], [373].
• Inclination of needle, [86].
• Induced currents, [Chap. XXV.];
• and work, [429];
• and lines of force, [432], [435], [438];
• direction of, [439].
• Induced magnetism, [Chap. III].
• Induction coils, [473];
• action of, [474];
• condensers of, [181];
• with telephone, [483].
• Induction, electromagnetic, [426];
• laws of, [440];
• static, theory of, [159];
• successive, [168].
• Inductive capacity, [169].
• Insulators, [Chap. VII.], [125].
• Internal resistance, [307], [314], [358], [362], [368].
• Iron and steel, [Chap. I].
• Iron, hardening properties of,
• [Exp. 4];
• impurities of, [1];
• kinds of, [2];
• soft, [10].
• Jar, Leyden, [179].
• Key, [233], [234].
• Lamp, arc, [485];
• incandescent, [486].
• Laws, of electrification, [121];
• of induction, [440];
• of magnetism, [29];
• of resistance, [349].
• Leclanché cell, [287].
• Leyden jar, [179].
• Lighting, [484], [485], [486].
• Lightning, [144], [a]; [218];
• rods, [220].
• Lines of force, about a wire, [385], [388];
• electric, [156];
• and induced currents, [432], [438];
• magnetic, [64], [73], [74], [80], [156];
• resistance to, [78], [397].
• Local action, [273].
• Local currents, [273].
• Lodestone, [93].
• Magnetic, bodies, [15];
• circuits, closed, [420];
• field, [62], [80];
• figures, permanent, [417];
• figures, [64], [Exp. 161], [162], [Exps. 168] to [171];
• force, lines of, [64], [80], [156];
• induction of the earth, [92];
• needle, [26];
• needles, balancing of, [88];
• needle, dip of, [86];
• problems, [33];
• saturation, [42];
• screens, [18];
• tick, [Exp. 160];
• transparency, [18].
• Magnetism, [Part I.];
• induced, [Chap. III.], [53];
• residual, [44], [53];
• temporary, [53];
• terrestrial, [Chap. V.];
• theory of, [42];
• of earth, [83];
• laws of, [29].
• Magnets, bar, [21];
• compound, [73];
• effect of breaking, [51];
• equator of, [13], [51];
• experimental, [407];
• kinds of, [11];
• natural, [93];
• poles of, [13], [25];
• practical uses of, [16].
• Mercury, [274].
• Motion, production of, [Chap. XXVI.], [445], [452], [455].
• Motors, electric, [477].
• Mutual attractions, [111].
• Natural magnets, [93].
• Needle, astatic, [251], [253], [254];
• magnetic, [26], [32].
• Negative electrification, [120].
• Neutral bodies, [102].
• Non-conductors, [312].
• Non-electrics, [134].
• North-seeking poles, [25].
• Ohm, the, [308].
• Ohm's law, [356].
• One-fluid theory, [145].
• Open and closed circuits, [266];
• cells, [286].
• Oxygen, [372], [373], [382].
• Peltier effect, [424].
• Pith-ball electroscope, [200].
• Plates or elements, [267].
• Polarization of cells, [278];
• effects of, [279];
• electric, [159], [164];
• electromotive force of, [373];
• magnetic, [56];
• remedies for, [280].
• Poles, [13], [25], [64], [92];
• consequent, [39];
• of coils, [392];
• of electrodes, [269];
• reversal of, [35];
• rule for, [31].
• Pole pieces, [56].
• Positive electrification, [120].
• Potential, [133],[144];
• energy, [103].
• Primary current, [441].
• Proof-plane, [209].
• Quantity, unit of, [354].
• Recorder, [Exp. 197].
• Relay, telegraph, [462].
• Repulsion, laws of electrostatic, [121];
• laws of magnetic, [29].
• Residual, charge in condenser, [197];
• magnetism, [44];
• magnetism of core, [Exp. 159].
• Resistance, coils, [309];
• effect of heat on, [343];
• electrical, [Chap. XVIII.], [305], [319], [321];
• external and internal, [307], [362], [368];
• internal, [314], [358];
• laws of, [349];
• to lines of force, [78];
• measurement of, [Chap. XIX.];
• unit of, [308].
• Retentivity, [44], [46].
• Reverser, current, [235], [237].
• Rheostat, simple, [344].
• Saturation, magnetic, [42].
• Secondary cells, [382];
• current, [441].
• Self-induction, [444].
• Series arrangement of cells, [364].
• Shocks, [188].
• Short circuits, [295].
• Shunts, [293].
• Silk, as insulator, [136].
• Single-fluid cell, [275].
• Single needle telegraph, [Exp. 194].
• Sounder, telegraph, [458].
• Spark, [144], [a].
• Static electricity, [Part II].
• Static electric machines, [216].
• Steel, [Chap. I.];
• kinds of, [2];
• magnetism of, [42], [46], [49].
• St. Elmo's fire, [222].
• Storage cells, [382].
• Successive, induction, [168];
• condensation, [199].
• Sulphuric acid, [258], [262], [314].
• Tangent galvanometer, [352].
• Telegraph, line, [459], [460];
• relay, [462];
• single needle instrument, [Exp. 194];
• sounder, [458];
• static, [130].
• Telephone, the, [479];
• Bell, [480];
• carbon transmitter, [482];
• with induction coils, [483];
• receiver, [481].
• Tempering steel, [8].
• Temporary magnetism, [53].
• Terrestrial magnetism, [Chap. V].
• Thermoelectricity, [Chap. XXIV.], [423].
• Thermopile, [425];
• home-made, [421].
• Thunder, [219].
• Transformers, [475].
• Transmitters, [480], [482].
• Two-fluid cell, [280], [281];
• care of, [282];
• chemical action in, [285].
• Two-fluid theory of electrification, [146].
• Unit of, current strength, [351];
• E. M. F., [297];
• of power, [355];
• quantity, [354];
• resistance, [308].
• Variation, angle of, [84].
• Varieties of electricity, [100].
• Volt, the, [297].
• Voltameters, [297], [353], [380].
• Water, composition of, [372].
• Watt, the, [355].
• Wheatstone's bridge, [324] to [330].
• Wind, electric, [155].
• Wire tables, [Chap. XXVIII].
• Yoke, use of, [406].
• Zero, potential, [144], [a].
• Zinc, chemical action with, [271];
• with commercial, [273].
• Zinc plates, reasons for amalgamating, [274].

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