THE CLASSIFICATION OF MARKET MILK. 
By A. D. Melvin, 
Chief of Bureau of Animal Industry , United States Department of Agriculture. 
In providing for the classification of milk, the primary object is to 
exclude all milk which may be harmful to the consumer and to pro- 
vide for milk that will be wholesome and nutritious. In doing so 
the restrictions should not be more burdensome than necessary to 
accomplish this result and should not eliminate milk as an article of 
diet for the poor. The danger of using raw milk from diseased cows, 
improperly constructed dairies, improperly handled, and various 
other causes, has been clearly shown, and it is therefore imperative 
that no raw milk be sold, except when those in authority know that 
it is safe to be used in that condition. Raw milk of the highest 
standard should be produced for the use of infants and invalids and 
for those who desire to use only such milk and who are willing to pay 
for the greater cost of production. A wholesome supply of raw milk 
which can be furnished without involving unreasonable cost should 
be provided for others. 
A third class includes undoubtedly the largest proportion of milk 
which is at present time furnished for consumption and is unsafe for 
consumption in the raw state. To immediately remove from con- 
sumption this supply would result in such an increase in the value of 
all milk as to place milk as an article of diet beyond the reach of the 
poor. 
It seems necessary therefore to provide some means of rendering 
safe all milk of doubtful quality, and this can only be done by pasteur- 
ization under supervision. The work of testing with tuberculin all 
cows supplying milk to a city of considerable size is an immense under- 
taking and must necessarily consume much time. Much time is 
required also in providing suitable cow stables, milk houses, and a 
pure water supply in all instances where such essential features are 
lacking. 
It is probable that from 15 to 25 per cent of dairy cows when tested 
with tuberculin will be found to react. These cows should be replaced 
by healthy ones. Facilities must also be provided for delivering milk 
at a reasonable temperature. It has been demonstrated that cows 
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