Page:Incandescent electric lighting- A practical description of the Edison system.djvu/110

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with a boiler pressure of 110 pounds, revolutions 223 and load 1,200 ampères, which is the equivalent of 2,725 lamps; therefore giving for indicated power furnished eleven and one-half lamps per horse power. This is for power developed, making no allowance for friction of engine and dynamo. The friction of the engine is less than five per cent, of its normal capacity.

Having in the above given a general outline of this plant, its cost and operating expenses. I now wish to call your attention to the points in connection with the type of engines, boilers, dynamos, underground system, etc., to be adopted in a station of this class.

Conclusions.

We will first consider the question of the engine. As already stated, in proposing the engine power of a station of this kind, we first have to consider the question of using either the Corliss or high-speed engine. Regarding the use of Corliss engines in a plant of this kind,