DRIVEN MACHINES 125 



load circuit breaker, false fuse blocks, etc., because 

 familiarity with these names, and the parts they rep- 

 resent gives the person confidence in charging the bat- 

 teries. Such knowledge also supplies a reason for the 

 one principal battery precaution, which is not to use 

 out all of the electricity the batteries contain. 



Those who have electric lighting plants on the farm 

 do not seem to feel the cost of running the plants, be- 

 cause they use the engine for other purposes. Gen- 

 erally manufacturers figure about 1 H.P. extra to run 

 a dynamo to supply from 25 to 50 lights. My experi- 

 ence with farm engines is that for ordinary farm work 

 such as driving the cream separator, working the pump* 

 and grinding feed, a two-horse power engine is more 

 useful than any other size. Farmers who conduct 

 business in the usual way will need a three-horsepower 

 engine if they contemplate adding an electric lighting 

 system to the farm equipment. 



Among the advantages of an electric lighting sys- 

 tem is the freedom from care on the part of the women. 

 There are no lamps to clean or broken chimneys to cut 

 a finger, so that when the system is properly installed 

 the only work the women have to do is to turn the 

 switches to throw the lights on or off as needed. 



The expense in starting a farm electric light plant 

 may be a little more than some other installations, but 

 it seems to be more economical in service when figured 

 from a farmer's standpoint, taking into consideration 

 the fact that he is using power for generating electric- 

 ity that under ordinary farm management goes to 

 waste. 



A three-horsepower engine will do the same amount 

 of work with the same amount of gasoline that a two- 



