560 
showing no physical evidences of tuberculosis may be affected with 
tuberculosis and secrete milk containing germs of that disease; also 
that the feces of such cattle are contaminated with that bacillus and 
particles of such feces can readily gain entrance into milk. It seems 
necessary, therefore, that pasteurization must be included for some 
time, or until all doubt as to the healthfulness of the milk is removed, 
in any classification of milk for city use. 
It is therefore recommended that the classification as recommended 
by the members of the conference appointed by the Commissioners 
of the District of Columbia to report upon the milk supply for the 
city of Washington be adopted as follows: 
CLASS 1. CERTIFIED MILK. 
The use of this term should be limited to milk produced at dairies 
subjected to periodic inspection and the products of which are 
subjected to frequent analyses. The cows producing such milk must 
be properly fed and watered, free from tuberculosis, as shown by the 
tuberculin test and physical examination by a qualified veterinary 
surgeon, and from all other communicable diseases, and from all 
diseases and conditions whatsoever likely to deteriorate the milk. 
They are to be housed in clean stables, properly ventilated, and to be 
kept clean. 
All those who come in contact with the milk must exercise scrupulous 
cleanliness, and such persons must not harbor the germs of typhoid 
fever, tuberculosis, diphtheria, and other infections liable to be con- 
veyed by the milk. Milk must be drawn under all precautions neces- 
sary to avoid infection, and be immediately strained and cooled, 
packed in sterilized bottles, and kept at a temperature not exceeding 
50° F. until delivered to the consumer. Pure water, as determined 
by chemical and bacteriological examination, is to be provided for 
use throughout the dairy farm and dairy. Certified milk should not 
contain more than 10,000 bacteria per cubic centimeter, and should 
not be more than 12 hours old when delivered. Such milk shall be 
certified by the health officer of the District of Columbia. 
CLASS 2. INSPECTED MILK. 
This term should be limited to clean raw milk from healthy cows, 
as determined by the tuberculin test and physical examination by 
a qualified veterinary surgeon. The cows are to be fed, watered, 
housed, and milked under good conditions, but not necessarily equal 
to the conditions provided for class 1. All those who come in contact 
with the milk must exercise scrupulous cleanliness, and such persons 
must not harbor the germs of typhoid fever, tuberculosis, diphtheria, 
