278 



BUTTER-MAKING. 



will not cool the room as effectively as ice, but in the absence 

 of ice this is better than no cooling at all. 



Cost of Producing One Pound of Butter. — The cost of pro- 

 ducing :i pound of butter \-aries at different creameries. Up 

 to a certain limit, the more butter that is being produced at 



Dead Air Space 



Ron of Til Outlets 



Fig. 167. — Cross-section of a sewage-disposal tank. (Wallace's Farmer.) 



one place the less will be the cost of production, that is, pro- 

 \'iding the creameries are otherwise equally well managed. 

 The Iowa State Dairj^ Commissioner has investigated this 



Fig. lOS. — Septic tank for creamery sewage disposal. (By Prof. J. Michels.) 

 The tank should be located in the ground with the top within a foot or 

 two of the surface. It may be constructed of planks. Brick, stone, or 

 concrete is preferable for durability. The tank should be built air- 

 tight except in two places, D and E. 



question and finds that the cost of production varies from 

 1.2 cents to 6 cents per pound. According to the reports sub- 

 mitted to the office of the State Dairy Commissioner, the 

 highest cost of production comes from a co-operative creamery 

 that makes a little less than 30,000 pounds of butter per year. 

 The lowest cost of production is submitted by a co-operati-\'e 



