60 REPORT OF DEPARTMENT or BACTERIOLOGY OF TH 
It should be clearly understood that in these studies of the 
action of milking machines the effort was made to run the 
machines in accordance with the directions of the manufac- 
turers except in so far as it was necessary to vary the condi- 
tions in testing specific factors. The barn conditions were 
inade to approximate as closely as possible those of a good 
farm dairy. There seems to be no reason why any dairy which 
is prepared to carry out the directions of the manufacturers 
may not confidently expect to reproduce the results here given 
provided the same care is exercised. As will be shown in de- 
tail, the quaiity of the milk produced by the milking machine 
depends almost entirely upon the exercise of intelligent care 
in operating it. 
The surprisingly low germ contents recorded in connection 
with these studies under ordinary barn conditions indicate 
that when its operation is fully understood the milking ma- 
chine may become an important factor in the production of 
“certified ” milk, where great stress is laid upon producing a 
milk with a low germ content. It is the intention later to 
bring our barn to a condition comparable to that under which 
certified milk is being produced and observe the effect of this 
change on the product of the milking machine, 
