346 



INDEX. 



Coherer, the Branly, 336 



Collector rings of the alternator, 126 



Combined resistance of a number of 



branches of a circuit, 47 

 Commutator of direct-current dynamo, 1 29 

 Compass correctors, adjustment of, 310 

 quadrantal, 304, 306 

 semicircular, 301 



errors, 300 



heeling corrector of, 310 



the, 62, 293 

 Concentrated charge, field due to, 179 



charges, attraction and repulsion of, 



180 

 Condenser, mechanical analogue of, 166 



potential energy of a charged, 170 



the, 1 60, 165 



Conductivity, definition of, 27 

 Conductors of electricity, I 

 Convective discharge, 214 

 Copper, electrolytic refining of, 5 

 Coulomb, definition of, l6l 

 Coulomb's Law of magnetic attraction, 64 

 Coulombmeter, the, 8 



the silver, 21 

 Crookes tube, the, 226 

 Current density at an electrode, 8 



measurement of, 276 

 Cycle, definition of the, 127 



Danneel's Electrochemistry, 5 

 Daniel 1 cell, see gravity cell 

 D' Arson val galvanometer, the, 113 

 Decay of current in an inductive circuit, 



149 



Declination, magnetic, 293 

 Demagnetization by reversals, 84 

 Diamagnetic substances, 87 

 Dielectric, inductivity of, 168 



strength, 174 



strengths, table of, 1 76 



the, 163 

 Dip, magnetic, 293 



needle, the, 293 

 Diplex telegraphy, 325 

 Direct-current dynamo, fundamental equa- 

 tion of, 131 



Direct-current dynamo, the, 127 

 Discharge by convection, 214 

 by disruption, 214 

 from metallic points, 218 

 Disruptive discharge, 214 

 Dissociation theory of electrolysis, appli- 

 cations of, 1 2 

 of electrolysis, the, 10 

 Dolezalek, The Theory of the Lead Stor- 

 age Cell, 1 8 



Doubler, the electrical, 196 

 Drop of voltage, 39, 40 

 Dry cell, the, 13 

 Dubois, H., Magnetic Circuit in Theory 



and Practice, 8 1 

 Duplex telegraphy, 326 

 Dynamo, direct-current, fundamental 



equation of, 131 

 the alternating-current, 125 

 the direct-current, 127 

 the, 117, 124 

 Dynamos, types of, 1 24 



Edison-LaLande cell, 15 

 Eddy currents, 1 36 



examples of, 136, 137 

 Electric absorption, 1 66 

 arc, the, 232 

 charge, 1 60 



measurement of, 161 

 units of, 161 



current, chemical effect of, I, 4, 5 

 direction of, 6 

 heating effect of, 4, 25 

 hydraulic analogue of, 4 

 magnetic effect of, I, 93 

 measurement of, by electrolysis, 



7 



strength of, magnetically de- 

 fined, 98 



discharge in gases, 224 

 field, direction of, 174 



due to a concentrated charge, 



179 



energy and tension of, 185 

 intensity of, 1 72 

 mechanical analogue of, 164 



