FARM MANAGEMENT 27 



seriously with the horse as a source of motive power. (Bu. Pit. Ind. 

 B. 170.) 



Owing to the initial cost of traction outfits for plowing, owners 

 of farms of from 160 to 500 acres may be deterred from their use; 

 but by combinations among neighboring farmers this difficulty can 

 be overcome. 



POWER ON THE FARM. 



Power is rapidly displacing hand and horse labor on the farm, 

 and the use of machinery will continue to increase. Engines are 

 now being used for pumping water for the home and for stock, and 

 to supply irrigation ; to operate creameries and butter factories, feed 

 cutters, grinders, corn shredders, threshing machines, motors for 

 plowing, mowing and reaping, electric lighting, etc. 



Engine and Fuel. The character of the engine and the fuel 

 to be used are becoming important and serious problems to the 

 farmer. The newest kind of fuel is alcohol. This is made from 

 the yearly crops of plants, and it may be said, in a sense, to be pos- 

 sible to produce an inexhaustible supply. What fuel is the most 

 economical depends largely upon the locality where it is to be used. 

 The fuel most commonly used at present is coal and crude petroleum, 

 but in many sections coal is expensive, and the supply of crude pe- 

 troleum may become exhausted, so the substitution of alcohol is a 

 matter of great consideration. 



It is easy to understand how an engine may operate without 

 understanding the well-known facts concerning explosive mixtures ; 

 but it is impossible to comprehend why engines should differ in fuel 

 consumption or horsepower, good regulation, or any other charac- 

 teristic without first studying in detail the influence of the mechan- 

 ism on the composition of the explosive mixture. 



Any fuel will burn when there is oxygen present in proper 

 quantity and when the fuel has previously been heated sufficiently. 

 This is true for any kind of combustion, such as the burning of wood, 

 coal, oil in a lamp or cook stove, or gas issuing from an illuminating 

 jet, as well as mixtures in exploding engines. When a fuel is mixed 

 with air containing the right amount of oxygen, or mixed with any 

 solid or liquid containing oxygen in the right amount, then ex- 

 plosive combustion is possible. If such a mixture be ignited at one 

 point by heating it by a flame, a hot plate, or an electric spark, the 

 combustion will travel through the entire mass of its own accord. 

 (F. B. 274.) 



One fuel may furnish more heat units than another, yet the 

 engine using the fuel supplying the lowest heat energy may have 

 greater advantages for use on the farm. From the best figures ob- 

 tainable it is possible to buy eight times as much energy for a given 

 amount of money in the form of cheap coal as in the form of low- 

 priced gasoline, or twenty-five times as much as in the form of high- 

 priced gasoline or kerosene. This being true, it might seem to a 

 casual observer as rather strange that gasoline should be used at all, 

 and the fact that it is used in competition with fuel of one-eighth 

 to one twenty-fifth its cost shows clearly that either the gasoline 



