vi Introduction. 



Modern dairying is attempting to build its more accurate 

 knowledge upon a broader and surer foundation, and in doing 

 this is seeking to ascertain the cause of well established pro- 

 cesses. In this, bacteriology is destined to play an important 

 role. Indeed, it may be safely predicted that future progress 

 in dairying will, to a large extent, depend upon bacteriologi- 

 cal research. As Fleischmann, the eminent German dairy 

 scientist, says: "The gradual abolition of uncertainty sur- 

 rounding dairy manufacture is the present important duty 

 which lies before us, and its solution can only be effected by 

 bacteriology." 



