FROM THE PRACTICAL VIEWPOINT 



were four samples taken at the outlet of the heater, 

 the holder, and so on. In the tables herewith com- 

 piled, only the average counts are indicated, in or- 

 der to avoid any bewildering mass of figures. It 

 should be therefore borne in mind that bacteria 

 counts here indicated are averages. 



In figuring out the percentage of reduction, 

 the relation between the bacterial content of the 

 raw milk and the milk as it leaves the holder is 

 considered. It will frequently be found that the 

 number of bacteria in the milk leaving the cooler 

 is higher than when it leaves the holding appara- 

 tus, and that this number is again increased when 

 the milk enters the bottles and cans. Usually un- 

 clean coolers, bottling machines and bottles are 

 responsible for this increase. 



Not all of the types of apparatus which are 

 illustrated and described in this book have been 

 tested by the writer as to their efficiency in the de- 

 struction of bacteria, and any omissions which may 

 be observed in the tables are not due to any inten- 

 tion on the part of the writer to slight any of them, 

 or to any desire to call attention more forcibly 

 to one kind of machine than to another. It simply 

 means that the results of tests are not available. 

 189 



