68 Report oF DEPARTMENT OF BACTERIOLOGY OF THE 
Salt solution.— The brine solution in which the tubes and 
teat cups are held between milkings contains approximately 
one part of salt to ten parts of water, the salt solution being 
renewed each week. About 50 quarts are needed to immerse 
the parts necessary for a dairy of 26 cows. Before being used 
these rubber parts and teat cups are rinsed with water to re- 
move the salt. . 
Sampling.— The Globe machine delivered the milk of two 
cows into a Single pail and the samples were taken from this 
mixed ‘product as it was being emptied. (See Plate III, fig. 1.) 
Samples of hand-drawn milk were made comparable with those 
from the machine by mixing the product of two cows which 
had been milked into a 13-inch open pail. The Burrell-Law- 
rence-Kkennedy machine delivers the milk of each cow separately 
and samples were taken from the milk of each cow as it was 
being poured from the milking machine. (Plate IV, fig. 1.) 
Unless otherwise stated the samples were taken . from the 
product of the first paix of cows at each milking. 
The details of the handling of the machines and the general 
barn management were under the personal supervision of one 
of us (S), who was present during the experimental runs of 
the machine in practically all cases. The samples for bacteri- 
ological examination were all taken personally by another of 
us (W) and full notes made as to the actual conditions under 
which the tests were made. 
Plating and incubation— The samples were taken to the 
laboratory and the plating completed within an hour. The 
medium used was as follows: 
Agar 15 grams 
Peptone (Witte) 10 grams 
Lactose, ¢. p. 10 grams 
. Beef extract (Liebig) 5 grams 
. NaCl 5 grams 
Water (distilled) 1000 grams 
The reaction was adjusted to 1.5 per ct. normal acid to 
phenolphthalein. This medium was chosen so that the plates 
