Page:Incandescent electric lighting- A practical description of the Edison system.djvu/137

 are the same as in the case shown in Fig. 3. This increases the total cost from $783 to $800, and necessitates using lamps of 3.18 watts per candle instead of 3.1,



to make the cost of operating a minimum.

In the case shown in the diagram. Fig. 5, the current costs 5 cents per h.p. per hour; the other conditions are the same