105 INDEX. The figures refer to tlit pages. Absolute measurements, 103, 104; history of, Gauss, Weber, 15. A. Committee, Jtc., 15. Accumulator, theory of, 34. Alternating discharges with inductorium and Leyden jar, 65. A npirt, electrodynamics, 10. Ampere i law, 70; experimen tal arrangements for show ing electrodynamical action, TO. .1 nperts theory, skctcli of, 74; generalization of, 75. Arc, voltaic, 58. Batteries, 92-94; history of, 13; one-fluid and two-fluid oxidizing agents in local action polarization, &c.,93. Battery of Leyden jars, 35. Hound and free electricity, 35 Howl, spherical, distribution on, Thomson, 33. Brush, 63. Capacity, coefficients of, 27. Cascade jars in, 35. Cell of Daniel I, different mo difications of, 93, J4; of (iiore, liunsen, ifec., 94. Chemical affinity, electrical measure of, Joule, 92. Circuit, linear, Ohm s law for, 42; action on, in magnetic field, G8. Circular current, magnetic action of, 71. Condensing electroscope, 34. Conduction, Gray, 4; general equations of, 41. Conductivity boxes, 45. Conductors, network of linear, Kirchhojf, 43; conjugate, 43. Conjugate functions, 33. Conservation of energy, Joufe, &.C., 14. Contact force, general law of, !-3 , Yalta s experiments, 83 ; Volta s law, 83; Kohl- i-ausch s researches, 83 ; Ilankel s experiment, 84; Thomsons demonstration, 85 ; Clijlont experiments, 85 ; uncertainty concerning, 85 ; from polarization, 86. Contact of conductor with non-conductor, 100. Contact of non-conductors, 99. Convection, electrolytic, llelm- holtz, 87; of heat, electric, Thomson, 97 ; Tail s conjec ture concerning, 97. Convective discharge, 64, G6. Convecto-inductive machines, Jloltz, Topter, rarity, Thom son, 101, 102, 103. Cnulomb, 9 ; his torsion ba lance, 18. Current, electric, general phe nomena and measure of, 40. Currents, mutual action of, when parallel and when inclined, 70. Decomposition of alkalis, Davy, 9 ; of water by electric cur- icnt, yicho tson and Carlis e, !) ; by electric spark, 9. Dielectric strength of gases, Ac., Harris, Riess, <fec., 60; effect of pressure, <fcc., on, Harris, 61 ; Faraday s re searches on, 61; Wiedemann, RMmann, 61 ; at high pres sures, 62 ; minimum for vacuum, 62. Differential galvanometer, 43. Discharge in fluids, 65; in solids, 66 ; in gases, mag netic action on, De la Rive and Pliicker, 74. Disruptive discharge, 69-66; theoretical considerations on, 60; progress of, 62. Distribution, electrical, Coul- lomb, 19, 20, 22-24 ; gene ral problem of, 27. Doubler, liennet s, Daricin, C acallo, and Xicholson, 10J. Earth s action on suspended current, 72. Electricity, positive and nega tive, JJufay, 4; theory of, 17. Electrics and non-electrics, Gilbert and Boyle, 3. Electrodes, temperature of, in discharge through gases, 64. Electrodynamics, theory of, Ampere, Weber, Xeumann, llelmholtz, Maxitell, 10, 66-74. Electrodynamometer, use of, in measuring electrolytic resistance, 49 ; Weber s ex periments with, 71 ; Am peres theory verified by means of, 71. Electrokinetic energy, 81; Thomson s theory of, 76. Electrolysis, Faraday, <fec., 13, Electrolytes, Ohm s law /or, 47; Faraday s law of con duction for, 47; his law of electrochemical equiva lents, 47; polarization and transition resistance with, 47 ; resistance of, Hors/vrd, Bcelz, Paalzoic, Kohlrausch and Xippoldt, Ewing and Macgregor, 48-50. Electromagnetic engines, his tory of, 10. Electromagnetic rotation, 72; discovered by Faraday, 10 ; his apparatus, 72; Ampere s theory of, 73 ; different ap paratus for. 73; of fluids, 73 ; of electric discharge, 74. Electromagnetism and electro dynamics, 66-75. Electromotive force, origin of, 83-103 ; measurements of Poggendorff and Clark, 86 ; dynamical theory of, Thom son, 90; calculated from chemical data, 90 ; limit of, in electrolysis, 90 ; question as to seat of, 99. Electromotive series two metals and one liquid, two liquids, one metal and two liquids, Ac., 86. Electrophorus, Yalta, 101. Electrostaticul theory, recent history of, ttrcen, Thomson, Gauss, Ac., 13. Electrostatics, mathematical theory, 24-36. Electrostatics, experi menial, recent history of, Faraday, Harris, Riess, <fkc., 14. Element of circuit, action on, in magnetic field, 68. Ellipsoids, distribution on, 30 Energy, electroklnetic, of two circuits, 76. Energy, laws of, in voltaic cir cuit, Joule, 89; Favre and Silbermann, 89; Thomson, 90. Energy, transformation! of, In electric circuit, 54, .fee. Equilibrium, electrostatic, con dition of, 26. Faraday, induction of electric currents, 11. Figures of Lichtenlerg, of Karsten, 66. Fishes, electrical, 8. Floating battery of De la Hire, 72. Force, electric, laws of, Cou lomb, 20, 21. Force, electrostatic, for any displacement, 29, 30. Franklin s researches, 6; por trait experiment, 58. Friction of powders, ifec., Arm strong s machine, 101. Frictional electricity, contact theory of, 99. Frictional electromotive series, Wilctt, Faraday, Riess, 100 ; Peclet s experiments, 100. Frictional machines, Ramsden, Le Roy, Nairne, 100, 101. Galvanometers, history of, 13; differential, 43. Gas battery, Groi-e, 87. Gases, rarefied, light effects in, 64. See also Dielectric strength. Glow, 63. Glowing of wires, 58. Gore s railway, 58. Greens theorem, 29. Heat, local, at electrodes, Joule, 90 ; Fatre and Sil bermann, Eosscha, 91 ; theories of Thomson, Joule, Bosscha, 92. Heating effects, 65-59 ; gene ral law of, 55; from dis charge of statical electricity, 56 ; from constant current in metals and electrolytes, 56 ; reversible at junctions. <fcc., 57 ; general theory of, 57. Images, electric, Thomson, 32 ; formed by surface electri fication, 66. Induction, Canton s discovery, 7, history of, 11; coefficients of, 27 ; through a surface, 25; between two fixed cir cuits, 81 ; in masses of metal, Plucker, Foucautt, 82. Induction of electric currents, 77-83; Fai aday s laws and Maxwell s statements, 75 ; deduction of laws from conservation of energy by Ile .mhiltz and Thomson, 75; of two circuits, 76 ; coeffi cients of, 76; Neumann s theory of, 76 ; Lenz s law of, 76; effect of material and thickness of wire, 76; effect of medium, 77; ex periments with electro- dynamometer, Weber, 77 ; Felici s researches on, 77 ; unipolar, 77, 78; coils with iron core, 78; physiological effect of currents, 78; by statical discharge, 78; cur rents of higher orders, 79. Induction, self, 76; Jenkin s observation, 79; Faraday s researches and theory, 79 ; Edlund s results 79 ; coeffi cient of, to measure, Max- tcell, 80; calculations and ex periments of Ilelmholt:, 80. Induction coil or inductorium, 103. Inductiye capacity, specific, Faraday, 36; Siemens, Can- gain, Gibson and Barclay, Boltzmann, 37; Schiller, Silou; liolttmann, 36. Inducto-convective machines, 101. Inversion, electric, TJiomson, 33. Iron, action of soft, 75. Joule s law for heating effect, 56. Kite experiment, franklin, 6. Lent, law of induction, 11. Level surfaces, theory of, 25. Leyden jar, Muschenbroect, ic., 5; theory of, 35. Lichtenberg s figures, 66. Light, electric, Guericke, 4; in Torricellian vacuum. Hawks- bee, 4 ; phenomena, 59. Lines of force, theory of, 26. Local action in batteries, 93. Magnetic pole, action of cur rent on, 70. Magnetism of rotation, Arago s discovery, 11; his experi ment, 82 ; Faraday s ex planation, 82 ; mathemati cal investigations, 83. Magnetization by current, Arago and JJaru, 10. Magneto-electric machines, Pixii, <fec., 12. Mince s method of measuring battery resistance, 50. Measurements, absolute, 103- 104. Mechanical effects, 65. Medium, insulating, 36-40. Melting of wires, 58. Multiple arc, 43, Kfumann, F. E., theory of in duction, 11. Oersted, magnetic action of current, 10. Ohm s law, 40-43 ; history of, 12 ; for electrolytes, 47. Oscillations,electrical, Tfiomson, 81 ; experiments of Fedder- sen, Schiller, <tc., 82. Peltier effect, 57. Phenomena, fundamental, 16. Physiological effects of electric currents, 78. Points and edges, density at, 31. Poisson, 9. Polarization, history of, 14; varieties of, 86; in batteries, 93; by gases, 87; maximum of, on what it depends, > W 8; decay of, 88; numerical results concerning, 88; un- polarizable electrodes, 89. Potential, electrostatic, theory of, 24-27; coefficients of, 28; fall of, in voltaic cir cuit, 42. Potential of magnetic shell, (17 ; of two circuits and of circuit on itself, Xeumann, 76. Potential energy, theorem of mutual, 28. Potential energy of system, 29. Pyroelectricity, Canton, Wilde, Bergman, <fec., 96; early history of, 8. Quantity, electric, 18, 19. Residual discharge, Kohl rausch, 39; Haxuell, HOJJ- kinson, 40. Resistance, measurement of, 43-46; history of measure ments, 13; of battery, 60; specific, general table of, 53; of transition, 87. Resistance in general, on, 51 ; of metals und alloys, data concerning, 51; of electro lytes, data concerning, 52. Resistance boxes, 45. Resistances, measurement of small, 45, 46 , of great, with electrometer, 46. Rheostat and rheochord 45. Screens, electrical, 29. Shell, magnetic, representing the action of a current, 67. Sine inductor, experiments with, 48, 49 Solenoid, 71. Spark, 62. Sphere with given force, 31. Spheres, two influencing, Pois son, 31. Standards of resistance, 44. Surface electrification, 66. Synthetical method, Green, 32. Systems, internal and exter nal, 29. Tension defined, 60; limiting 60; positive and negative, 61, 62. Theories, speculative, of elec trical phenomena, 104 ; con tact and chemical, of voltaic circuit, 14. Theory, one-fluid, Franklin, C; one-fluid, Carendith, 8; one- fluid, ^Epinus, 8; two-fluid, Symmer, 7, Thermoelectric diagram, Tail, 97. Thermoclect ric inversion, Cum min g, 96. Thermoelectric series, Seebeck, 94. Thermoelectricity, 94-99; his tory of, Setbeck, Camming, Peltier, Thomson, <fec., 11 ; Seebeck s discovery, 94. Thermoelectrometer, Harris and Riess, 55. Ihermoelectromotive force, order of magnitude of, 96; lesults of Magnus, 95; effects of strain, <tc., on, Thomson and Le RO-UJ, 95; in circuits of one metal, 9(! ; Thomson s theory of, 96,97; Tail s addition to Thomson s theory, 97; his experiments and results, 98. Thomson effect, 57, 97. Torsion balance of Coulvml, 18. Transmission of electricity, Watson, 5. Trerelyan rocker, 58. Unit, electromagnetic, of cur rent strength, 71 ; of elect romotive force, 75. Units, electrostatic and elec tromagnetic. 41. Vector potential of magnetic shell, 68. Velocity of electricity, W><eat- stone, 63. Volatilization of wires, *c., 58. Water-dropping electric ma chine, Thomson, 102. Weber, 10 ; his experiments with electrodynumometei, 71. Wfiealstone s bridge, 44,
VIII. 14