INDEX 



193 



Pressure in mercury arc, 94. 

 Pressures greater than one atmos- 

 phere, 73. 



Pringsheim, Lummer and, 43. 

 Puccianti, 144. 

 Pyrometer, 44. 



Quartz tubes for mercury arc, 100. 



R 



Ranchaud, Pollock and, 52. 



Rasch, 67. 



Rectifier, mercury arc: 



three-phase, 120. 



single-phase, 122. 

 Reich, 45, 49, 165. 

 Residual E.M.F., 35. 

 Resistance : 



of arc, 9, 28. 



in series with arc, 22. 



negative, 31. 



after removal of E.M.F., 38. 

 Relschinski, Kuch and, 100, 135. 

 Retschinski, Stark and Schaposchni- 



koff, 83, 96, 97, 168, 178, 183. 

 Rey, 132. 



Richardson, O. W., 159, 164. 

 Rogers, Firth and, 22, 32. 

 Rosetti, 41. 



Rossler and Wedding, 137. 

 Rowland, Duncan and Todd, 73. 

 Ruhmer, 148. 

 Russ, Grau and, 63, 85. 

 Ryan, 140. 



Sahulka, 69, 118. 



Salts, effect of, in arc, 55. 



Seal, Urbain, and Feige, 103. 



Schaposchnikof, Stark, Retschinski 



and, 83, 96, 97, 169, 178, 183. 

 Schenkel, 101, 178. 

 Schultze, 48, 67. 

 Sharpe, 133. 

 Silent arc, 21. 

 Simon, 16, 109, 146, 151. 

 Simon, Malcolm and, 15, 48, 64, 83. 

 Skinner, 168. 



Sodium alloy for electrodes, 82. 

 Solid carbons, 9. 



characteristic curves with, 13. 

 Spark compared with arc, 2. 

 Spectrum of carbon arc, 142. 

 Stability of arc, conditions for, 18. 

 Stark, 82, 99, 156, 164. 

 Stark and Cassuto, 163. 

 Stark and Kuch, 81. 

 Stark, Retschinski and Schaposchni- 



kojf, 83, 96, 97, 168, 178, 183. 

 Static converter, 120. 

 Statical characteristic curves, 16. 

 Stefan-Boltzmann law, 42. 

 Steinmetz, 114, 145, 180. 

 Stenger, 37, 74. 

 Stewart, Merritt and, 177. 

 Sulphur dioxide, arc in, 85. 

 Swendler, 29. 

 Swinton, 177. 



Telephony, wireless, and arc, 146. 

 Temperature of: 



gas in carbon arc, 40. 



anode of carbon arc, 40. 



variation of, 44. 



arc in vacuum, 81. 



mercury arc, 91. 

 Terminals, see Electrodes. 

 Theory of arc, 156. 



