454 



INDEX TO VOLUME II. 



COILS. 



Coils, resistance, of German silver 

 wire, 78 ; testing of under water 

 pressure, 49. 



Comparison of formula with experi- 

 ments on increased resistance of 

 metals with temperature, 148. 



Competition for cheapness, bad, for 

 quality of work, good, 194. 



Compound paying-out and picking- 

 up machine, action of, 140 ; advan- 

 tage of in recovering cable, 140 ; 

 description of, 140. 



Conductivity of copper, diagram of 

 variation of, 96 ; diminished by 

 admixture, 66 ; variation of, 66. 



Conductivity (of gutta-percha, 66 ; 

 decreased by hydrostatic pressure, 

 49 ; temperature, effect of on, 

 49), of insulating coating in terms 

 of resistance, 78 ; Matthiesen's in- 

 vestigations of, 78 ; (of platinum, 

 affected by metallic admixture, 

 143 ; affected by mode of produc- 

 tion, 143 ; table of variation of, 

 143 ; of wire of electric pyro- 

 meter, no change in, 124). 



Conductor of copper wires, strand of, 

 twisted, 65 ; of copper wire rope 

 insulated for dynamo-electric 

 locomotion, 243 ; eccentricity of, 

 in insulating covering, how caused, 

 66 ; of high conductivity, insu- 

 lating coating as thick as possible, 

 material of least specific conductive 

 capacity, 30 ; size of, to transmit 

 1,000 horse-power, 210; size and 

 weight of, in relation to distance, 

 192, 193 ; of submarine cables, 14, 

 15, 28, 91, 107. 



Continental governments, electric 

 telegraphs established by, 22. 



Continuous and alternating currents 

 compared, 200. 



Continuous growth, Schiibeler's ex- 

 periments on, 236. 



Continuous supply of carbons to 

 horizontal electric light, 239. 



CUTTING OR SHEARING. 



Control tests for cables, viz., in 

 manufacture, joining and covering, 

 and paying out, 58. 



Cooke and Wheatstone needle tele- 

 graph, 37. 



Copper, conductivity of, diminished 

 by addition of foreign matter, 66 ; 

 Matthiesen's investigations of, 48; 

 varies. 66, 96. 



Copper conductors, tests to ascertain 

 conductivity of, 48. 



Copper, increased resistance of with 

 rise of temperature, 85, 154 ; 

 oxygen, difficulty of removing, 

 from, 66 ; containing phosphorus 

 less soluble in sea water, 110 ; 

 pure and commercial, regarding, 

 48 ; stretching of, and assuming 

 serpentine form within insulating 

 covering, 107 ; wires, conductor of 

 strand of, 65. 



Corrosion of iron sheathing to cables, 

 113. 



Cost of electric and oil light, 208. 



Covering wires with india rubber, 

 machine for, description of, 69 ; 

 new method founded on adhering 

 property of fresh-cut surfaces of 

 india-rubber under pressure, 67, 

 68 ; old method with spiral strips, 

 objection to, 68 ; Silver's method, 

 68. 



Crampton in 1851 succeeded in lay- 

 ing sheathed submarine cable from 

 Dover to Calais, 26. 



Current generator, conductor and 

 receiver for maximum effect at a 

 distance, consideration of, 24. 



Currents of great power, generating, 

 24. 



Currents of high electric motive 

 force travel farthest through 

 cables, 32. 



Cutting or shearing, pressing and 

 guide rollers for india-rubber 

 machine, 69. 



