l8o PRACTICAL DAIRY BACTERIOLOGY 



practically impossible for the dairy to meet that standard under 

 the old conditions. When a standard is adopted the dairyman 

 is usually supplied with directions for improving the methods 

 and producing a better milk. The application of these methods 

 becomes more and more rigid as the dairyman finds that his 

 milk is likely to be condemned or rejected, because it fails to 

 reach the bacteria standard. There is no question that with the 

 improving of the dairy conditions and care in the production 

 of the milk there results an improvement in the grade and a 

 greater wholesomeness of the milk; hence it is that the adop- 

 tion of numerical standards has had a tendency to raise the 

 quality of the milk furnished in the city. As fast as the dairy- 

 man can be taught to use better methods in dairies, so fast will 

 the danger associated with this product be reduced and tend to 

 disappear. Care means safety, and the extent of the care is 

 the extent of the safety. Inasmuch as numerical standards do 

 bring about greater carefulness on the part of the dairyman 

 they have been and are of emphatic value. Practically it has 

 been found that in cities where a numerical standard has been 

 set and where an attempt has been made to enforce such a 

 numerical standard as thoroughly as possible, there begins al- 

 most at once an improvement in the quality of the milk. The 

 number of bacteria becomes smaller, and the death rate of chil- 

 dren falls in proportion. Hence, a numerical standard is of 

 value in raising the type of milk and even reduces the danger 

 of its being the cause of either specific or general diseases. 



Qualitative Analysis of Milk Bacteria. It is evident that a 

 very much better knowledge of market milk could be obtained 

 if it were possible by some simple means to determine not only 

 the number of bacteria but their kinds. Such a complete analysis 

 is not possible by any means yet known. The detection of dis- 

 ease germs is, as yet, practically out of the question. But a 

 bacteriological analysis may be made that gives much more in- 

 formation than the simple determination of numbers, since the 



