CONTROL OF CITY MILK SUPPLY 229 
a working knowledge along the lines suggested. 
Another matter for milk inspectors to remember is the 
fact that all unsanitary conditions are not necessarily the 
result of willful neglect or transgression. They may be 
the result of ignorance. In this connection it should be 
remembered that dairy inspection is a comparatively new 
matter and the ideals of many of the inspectors and fram- 
ers of health regulations can be attained only after months 
of patient education. Bacteriology itself is a compara- 
tively new science and it is, therefore, not so remark- 
able that there should be so much ignorance regarding 
bacteria and sanitation in general. 
A score card for judging dairy farms will be found 
in the appendix. 
Tuberculosis and Tuberculin Testing. Undoubtedly 
one of the most pressing problems confronting the city 
milk trade is the matter of obtaining milk from tuberculin 
tested cows. Numerous cities throughout the country 
have endeavored in the past, or are endeavoring at the 
present time, to pass and enforce ordinances requiring 
all milk to come from herds which the tuberculin test 
has shown to be free from tuberculosis. The opposition 
to such ordinances by milk producers is sometimes ex- 
tremely fierce, as recently experienced by the city of Mil- 
waukee. The producers objected to the ordinance re- 
quiring cows to be tested for tuberculosis, maintaining 
that the tuberculin test was not reliable. The matter was 
finally carried to the supreme court, but the courts affirm- 
ed the reliability of the tuberculin test in every case. 
The Tuberculin Test: The usefulness of this test as 
a diagnostic agent rests upon the fact that when a sub- 
stance called “tuberculin” is injected under the skin of 
an animal, the injection is followed by a rise of tempera- 
