108 STORRS AGRICULTURAL EXPERIMENT STATION 
PURPOSE OF THESE EXPERIMENTS. f 
The work with the milking machines conducted at this 
Station has been divided into two parts, the problems relating 
to yield and percentage of butter fat, together with the effect 
of the machines upon the cows, has been under the direction 
of Professor C. L. Beach, whose report is given in this 
bulletin. The problems bearing upon the sanitary conditions 
of the milk, including methods for cleansing and sterilizing 
the machines, have been under the direction of the writer. 
The purpose of the work in connection with the sanitary fea- 
tures of the machines, has been to determine the effect upon. 
the germ content of the milk drawn by the machine compared 
with milk drawn by hand under the same conditions. At the 
same time, a study of the care necessary to keep the machines 
clean and in sterile condition has been made. 
METHOD OF EXPERIMENTS. 
The machines were first installed at the College barn in 
October, 1905, and have been used continuously ever since 
that date. At first only a few cows were milked by the 
machines. In order to determine the effect of the machines 
upon the germ content of the milk, samples were taken from 
the milk of an equal number of cows, one group being milked 
by the machine and the other by hand at the same milking. 
The mixed milk from several cows was taken in order to 
eliminate differences due to individual germ content of the 
different udders. From time to time, the groups of cows 
were alternated so that those being milked by hand during one 
period were milked by machines during the next, and those 
milked by machines in the first period were milked by hand 
during the second period. From time to time the methods 
for cleansing and sterilizing the machines were varied in order 
,_ to determine the amount of care necessary to keep the ma- 
chines in sanitary condition. 
It should be borne in mind that all of these experiments 
were made in the College barn where the condition of 
cleanliness is somewhat better than the average, and the ma- 
chine drawn milk is compared with milk drawn by hand into 
the Stadtmueller covered pail, so that the machine milk is 
compared with a grade -of hand drawn milk considerably 
better than would. be obtained in the ordinary barn under 
usual conditions. 
