CHAPTER LXXXI 

 THE ACETYLENE LIGHTING PLANT 



The Principle of the Acetylene Plant. When a lighting 

 system for the farm is desired which will furnish the equal of 

 city service, the acetylene plant is one of the first to receive 

 consideration. Acetylene gas is made by bringing calcium 

 carbide in contact with water. In portable lamps the water 

 is allowed to drip upon the carbide; but with larger plants, the 

 carbide is fed into a rather large tank of water mainly to keep 

 the temperature of the gas as low as possible. The heating 

 of carbide and water is like that of unslaked lime and water, 

 and the resulting residue is the same nothing more or less 

 than common whitewash. 



Calcium Carbide. The calcium carbide is made by sub- 

 jecting a mixture of coke and lime to the intense heat of the 

 electric furnace. The resulting product is of dark-gray color 

 with a slightly crystalline structure. The carbide industry 

 is practically monopolized in this country by the Union Car- 

 bide Sales Company, from which all purchases must be made. 

 Distributing depots are located at various points throughout 

 the United States, there being one in each state, or perhaps 

 more in some instances. The cost of carbide at these depots 

 at the present time is $3.75 per hundred pounds. It is shipped 

 in metal cans as third-class freight. The carbide is no more 

 dangerous than unslaked lime; the only precaution necessary 

 is to keep it free from moisture. There are four sizes of car- 

 bide carried regularly in stock; viz., Lump, Egg, Nut, and 

 Quarter. The last two sizes, Nut J4 inch by % inch, and 

 Quarter, % inch by I/ 12 inch, are the two commonly used in 

 carbide feed generators. 



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