<-u\TENTS xiii 



PAGE 



194. Arc Regulation 428 



195. Flame Arcs 429 



196. The Metallic Electrode or Magnetite Lamp 431 



l'.7. The Mercury-arc Lamp; the Moore Tube; the Nernst Lamp. 433 



Photometry .435 



igg. Photometry 435 



199. The Bunsen Photometer .435 



200. The Lummer-Brodhun Photometer 437 



Portable Photometers - 438 



201. The Sharp-Millar Photometer . . 



202. The Rousseau Diagram 440 



203. Reflectors 442 



204. Interior Illumination 444 



205. Street Illumination . . 447 



206. Floodlighting 450 



APPENDIX A 



CIRCULAR MEASURE THE RADIAN 453 



APPENDIX B 



I KKiONOMETRY SlMPLE FUNCTIONS 453 



APPENDIX C 



FUNCTIONS OF ANGLES GREATER THAN 90 455 



APPENDIX D 



SIMPLE TRIGONOMETRIC FORMULAS 457 



APPENDIX E 



M ATHK'MATK A!. TALE8. NATURAL SlNES AND ( 'osiNES 458 



APPENDIX i 



\\M u\i. T\N<;ENT8 AND COTANGENTS . 460 



AI'I'KNDIX G 



HUMS OF NUMBBftH 462 



MTI.MHX II 



RESISTANCE OF COPPER Win. OHMS PER Mm I 464 



kPPBNDO 1 



(E PER SINGLE CONDUCTOR, OHMS PER MILE. . 466 



