\ 
COMPARATIVE STUDIES WITH COVERED MILK PAILS Ql 
with the conditions of cleanliness existing in the stable. In 
the College barn 85 per cent. of the bacteria were excluded 
in one series and 83 per cent. in the other series by the use 
of the cover. This represents the value of the pail in the 
best of the three stables. In the second barn where the actual 
conditions of the stable and the cows were good but the feed- 
ing and brushing at milking time filled the atmosphere with 
dust, 95 per cent. of the bacteria were excluded by the use 
of the cover while in the third stable where the conditions 
were decidedly unsanitary and representative of the worst 
grade of dairy conditions the use of the cover kept out 97 
per cent. of the bacteria which normally fell into the open 
pail. This series of tests will serve as a fair indication of the 
value of such a cover for the production of milk relatively 
free from stable contamination. The relative advantage 
gained by the use of the cover increases as the unsanitary 
conditions of the stable increase even though the numbers 
of bacteria which gain access to the milk drawn into the 
covered pail in such cases may be many times higher than 
would be obtained in stables where better conditions existed. 
The latest development in the way of covered pails is 
shown in Fig. 32. Like all the others the effort in this case 

Fic. 32—The latest development in covered milk pails. 
