Page:Incandescent electric lighting- A practical description of the Edison system.djvu/141

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lamps are only half as good. The minimum total cost is doubled, but the maximum

Lamps 50 cts. each—Life 600 hrs. at 3 Watts per Candle.

Current costs 10 cts. per ㏋. per hour.

Fig. 9.

efficiency is the same as in the previous case.

In this case, Fig. 10, the current costs one-half of that assumed in the previous