132 Dairy Bacteriology. 



narrow cans which are placed in hot water. In the 

 household, milk may be treated by placing the filled 

 bottle in a pail having a false bottom so the bottle shall 

 not be broken when the pail is placed on the stove. The 



FIG. 30. A PASTEURIZER FOB USE IN THE HOME. 

 A milk bottle with a tumbler for a cover. The cover pre- 

 vents the formation of the "scalded layer" on the milk dur- 

 ing the heating and also protects the mouth of the bottle 

 from dust. 



pail should be filled with water so that its level is about 

 the same as that of the milk. The water is then heated 

 to the desired temperature, maintained for the requisite 

 period of time, and is then cooled as rapidly as possible. 

 During the heating, the mouth of the bottle should be 

 covered, either with an inverted glass tumbler, or the 

 paper cap may be left in place, simply punching a small 

 hole through it so as to permit of the insertion of a 

 thermometer. 



