an Incandescent Paper-carbon Horseshoe Lamp. 29 



IV. Determination of 'power consumed by lamp only in main- 

 taining light of different intensities. 



No. of 



cells of 



Deflec- 

 tion of 

 galvano- 

 meter. 



Current, 

 in webers 



Eesist- 

 ance of 



Horse- 



Candle- 



power. 







battery. 



per 

 second. 



lamp. 



power. 



Maximum. 



Average. 



8 



230 



•Ill 



114-0 



•002 









9 



26-2 



•129 



1120 



•0025 



Just visible. 





10 



32-0 



•164 



111-0 



•004 



Dull red. 





15 



424 



•239 



1060 



•008 



Cherry- red. 





20 



54-0 



•361 



94-0 



•016 



•016 





25 



59-5 



■445 



90-0 



•024 



•10 



•07 



30 



65-6 



•578 



84-4 



•038 



•59 



•41 



33 



67-3 



•626 



84-0 



•044 



•83 



•58 



34 



67-9 



•645 



83-3 



•046 



1-10 



•77 



35 



68-7 



<672 



82-5 



•050 



1-5 



1-05 



40 



72-1 



•811 



80-0 



•071 



4-5 



3:1 



45 



73-9 



•908 



77-6 



•086 



9-2 



6-4 



50 



763 



1-079 



74-5 



•116 



20-0 



140 



Fig-. 4. 



HORSE-POWER. 



As regards the economic relations of this subject, it will be 

 intereresting to notice that, an average light of 14 candles 

 being obtained at the expense of 01 16 of a horse-power in 

 electric current, each horse-power of electric energy would 

 furnish 120 candle-power in these lamps. To obtain this 

 horse-power of electric energy, however, considerably more 



