4 6 4 



INDEX TO VOLUME II. 



HEMP COVERING OP CABLES. 



Hemp covering of cables, attacked 

 by marine insects, 99 ; as packing, 

 119. 



Henley, dial instruments of, 23 ; 

 double-needle telegraph of, 37. 



Higgs, P., dynamo-electric appara- 

 tus, recent improvements in, dis- 

 cussion of paper by, 187 193. 



Highton, B., on codes, 42 ; on double- 

 needle system, 42 ; on electric 

 apparatus and batteries, 41 ; on 

 insulation, 42 ; (on magneto-elec- 

 tricity, .failure of, 41 ; and voltaic 

 electricity, 41) ; on Newall's sub- 

 marine telegraph system, 41 ; sub- 

 marine telegraph system of 1850, 

 41 ; telegraph arrangements of, 

 reference to, 23 ; underground 

 system, failure of, 41. 



Holmes, Prof., produced in 185G 

 magneto-electric machine, such as 

 still illuminates lighthouses in 

 France and elsewhere, 199. 



Hopkinson, J., investigations regard- 

 ing dynamo-electric machines, 208. 

 216, 242. 



Horizontal electric light, 219, 237. 



Horticulture, dynamo electricity 

 valuable adjunct in, 220, 227, 247, 

 258. 



House's type-printing instrument, 

 23. 



Houston and Thomas, properties of 

 dynamo-electric machine exam- 

 ined by, 216. 



Huggins, W., recent application of 

 electric arc to astronomical re- 

 search, 222. 



Hughes's microphone and Bell's 

 telephone, points of analogy of, 

 196. 



IMPROVED electric telegraph by 

 Siemens, W. E., paper on, by 

 Siemens, C. W., 3, 4. 



India-rubber covered wire, advan- 



INDUCTIVE CAPACITY, 

 tages of, 71 ; construction of outer 

 coating of, 70 ; severe tests of, 72. 



India-rubber covering machine, 61 

 105 ; applicable to other purposes, 

 70 ; exhibition of in action, 71. 



India-rubber, effect of temperature 

 on, 104. 



India-rubber and gutta-percha 

 covered cables, comparison of, as 

 to cost, 74 ; as to endurance, 74 ; 

 as to insulating powers, 72, 99. 



India-rubber, gutta-percha, and 

 Wray's mixture as insulating 

 materials, 83 ; inductive power 

 of, compared, 73. 



India-rubber, insulating power of 

 high, inductive low, 67, 105 ; in- 

 troduced by Jacobi in 1846, 7, 

 138 ; liquefaction of, in water due 

 to oxidation, Prof. Miller on, 105 ; 

 machine for covering telegraph 

 wires with, 68, 69 ; soluble in 

 water, 101 ; temperature, effects 

 of, less than on gutta-percha, 72. 



Indo-European telegraph,guaranteed 

 as neutral property by govern- 

 ments, 194, 195. 



Induced currents, how produced, 

 45 ; in submarine lines, 45. 



Induction, Faraday's lecture on, 40 ; 

 phenomenon of, exhibited by 

 Clark, L., to Professors Faraday 

 and Airy in 1854, 40 ; voltaic in 

 submarine cables, 31. 



Inductive action, Faraday's concep- 

 tion of. 54. 



Inductive capacity, of cable, import- 

 ance of knowing, 54 ; of gutta- 

 percha independent of its conduc- 

 tivity, 56 ; of insulated wire, 

 formula for, 54 ; measured by 

 deflection of galvanometer needle, 

 55 ; method of ascertaining, 79 ; 

 unit of, 54 ; of wires covered with 

 gutta-percha or india-rubber, and 

 with gutta-percha and india-rubber 

 at different temperatures, 102. 



