84 BULLETIN 642, U. S. DEPARTMENT OF AGRICULTURE. 
pail were used at the same milking; in each case the bacterial count 
is shown above the disk. During the work the manure was removed 
from the stable only twice a week, and as a result the cows were 
extremely dirty. A study of the disks shows that in nearly every 
case when the small-top pail was used there was less sediment in the 
‘milk. The most striking difference is shown in sample 21. In some 
samples, however, there was apparently little or no difference, and 
when the disks from both the small-top and open pails showed little 
sediment there was, as a rule, less relative difference between the 
disks from the two types of pails. 
The average number of bacteria per cubic centimeter in the 30 
samples from the small-top pail was 29,263 and in milk from the open 
pail 87,380. The most striking difference in the bacterial count is 
shown in sample 10, where samples from small-top and open pails 
contained a large quantity of sediment. So far as could be judged, 
one kind of pail contained about as much as the other, but the bac- 
terial count of the milk from the small-top pail was 166,000 and 
from the open pail 940,000 bacteria per cubic centimeter. It is inter- 
esting to note that in the majority of cases in which the sediment 
disks showed a large quantity of manure there was a relatively low 
bacterial count. Occasionally a sample showed a large quantity of 
sediment and a high count, while other samples containing a similar 
amount had a low count. This is well illustrated in samples 10 and, 
21, which represent sediment in milk from the open pail and may 
be explained by the variation in the number of bacteria in samples of 
manure. : 
When the cows were clean and the udders free from visible dirt 
there was much less difference in the sediment in milk from the 
small-top and open pails, as is well illustrated in Plate IV, which 
shows the sediment disks of milk drawn in small-top and open pails 
under those conditions. The cows were kept clean, the manure was 
removed daily from the stable, and the udders were wiped with a 
damp cloth just before milking. One of the cows and the interior of 
the barn are shown in figures 14 and 15. It must be remembered 
that the sediment disks represent the sediment in unstrained milk. 
Of the 10 samples examined, some showed practically no difference 
in the quantity of sediment in milk from the small-top and open 
pails, but as a rule the small-top pail contained less sediment and a 
slightly lower bacterial content. The average number of bacteria 
per cubic centimeter from the small-top pail in the 10 samples was 
2.410 and from the open pail 5,740.. It will be noted in sample 2 | 
that milk from the open pail showed 21,300 bacteria per cubic centi- 
meter, which raised the average of all the samples from the open 
pails. 
b 
