176 FARM SEPARATORS 



bulls are used for this purpose. The process does not usually 

 last very long, and the work is not considered heavy. Steam is 

 good power, but it is hardly ever obtainable on the farm. 

 Small gasoline-engines are also used very successfully. 



The machine should always run smoothly in order to get 

 efficient skimming. It should never be stopped and started with 

 a jerk. If it is started slowly there will be less danger of breaking 

 any o* the gearing parts. The bowl and inside parts should be 

 kept from rusting as described previously on page 167. The 

 bearings should be well oiled. It is a good plan to have an extra 

 bearing or two on hand, so that if one happens to wear out 

 another one can be put in. The bearings should be cleaned at 



Progeny of a 

 single germ in 

 twelve hours 



FIG. 59. Showing the effect of cooling milk on the growth of bacteria. The bene- 

 ficial results of early chilling are readily apparent. (From Bui. 62, Wis.) 



intervals. When kerosene is occasionally used on the bearings 

 they do not need to be cleaned so often, because it keeps them 

 from gumming. The machine should be turned at the proper 

 speed, as indicated in the directions. A thicker cream will 

 result from rapid turning; consequently more skim-milk will be 

 obtained. Slow turning causes inefficient skimming and thinner 

 cream. 



Care of Cream on the Farm. The first step in the production 

 of good cream is clean milking. This can be accomplished only 

 when barn, cows, and utensils are clean. It is a good plan to 

 dampen a cloth, and wipe off the cow's udder and sides previous 

 to each milking. The milker should never wet his hands while 



