sila 
APPLICATIONS OF BACTERIOLOGY IN EUROPE. 73 
between dairying in Europe and in America is the slight use of 
ice in the European dairies. The milk which is brought into 
the cities is almost never cooled with ice. Even in the 
northern countries like Denmark, where ice might be 
supposed to be at least as easily obtained as in New England, 
we find that the use of ice is comparatively slight, and the milk 
which is brought into the cities is not brought in upon ice cars, 
but is hurried in as quickly as possible without any attempt 
at artificial cooling. Under these conditions, of course it 1s 
clear that the value of the original cooling of milk to as low a 
temperature as possible with cold water is a very great one. 
It is the one universal means of cooling milk now adopted in 
Europe. 
MILK AS A DISEASE DISTRIBUTOR. 
Leaving, now, such miscellaneous effects we notice the 
changes which the knowledge of milk as a distributor of dis- 
ease has produced in dairy methods. The first fact which 
comes to our notice is that there is everywhere an endeavor 
made to exclude from the herd which supplies public milk 
every animal with any trace of udder disease, no matter what 
that udder disease may be. It has been shown conclusively 
that udder diseases are always sources of danger to one who 
drinks the milk. Sometimes these troubles are of tuberculous 
nature, and then there is danger of tuberculosis. More com- 
monly, however, the udder troubles are not tuberculous. But 
the bacteria which get into the milk from a simple inflamed 
udder are frequently those which cause intestinal troubles in 
children and in adults. Evidence is abundant and satisfactory 
which shows that diarrhoeal troubles in mankind are in many 
cases to be traced to bacteria that come from various kinds of 
diseased udders. For these reasons it is recognized every- 
where that all animals with udder diseases should be separated 
from the dairy-supplying herd. It is of course not pretended 
that such a result is accomplished in European herds. It is 
an extremely difficult matter to exercise a control upon the 
herds of the individual farmer, but the attempt is being made 
by distributing information and by police regulations to ac- 
complish the result as thoroughly as possible. 
~ A second result has been in teaching the health authorities 
that there is great danger to the public health in allowing milk 
