460 
Table No. 2. — MilTc from a healthy coio (No. 1). 
[Immediately after milking contained 500 bacteria per cubic centimeter.] 
Bacteria per cubic centimeter at different ‘ 
temperatures. 
Time after milking. 
Room temper- 
ature, 26° to 
29° C. 
15° C. 
37° C. 
2 hours 
1,300 
700 
400 
7,800 
29, 000 
340,000,000 
Innumerable. 
Sour. 
4 hours 
900 
500 
600 
1,200 
80, 000 
1,380,000 
89,000,000 
Sour. 
11, 300 
38,000 
342,000 
50,000,000 
Sour. 
6 hours 
8 hours 
10 hours 
24 hours 
48 hours 
72 hours 
96 hours 
Table No 3. — Milk from a healthy coio (No. 1). 
[Immediately after milking contained 8,300 bacteria per cubic centimeter.] 
Time after milking. 
Bacteria per cubic centimeter at various 
temperatures. 
Room, 26° to 
29° C. 
15° C. 
37° C. 
2 hours 
8,000 
3 hours 
2,000 
2,000 
2, 000 
4 hours 
6. 000 
5 hours 
2,000 
6 hours 
2,000 
1,000 
6,000 
7 hours 
1,000 
20,000 
8 hours 
1,000 
1 5,000 
166,000 
THE EFFECT OF TEMPERATURE. 
Temperature has a decided influence upon this phenomenon. 
AMien the milk is kept warm (37° C.) the decrease in the number 
of. colonies is striking, but of short duration. When the milk is kept 
cool (15° C.) the decrease is less marked, but more prolonged. This J 
is well illustrated by the curves. Figs. 9 to 14. ! 
These curves were plotted from the following tables, which show 
the germicidal properties of milk for individual species of bacteria. 
The experiments were conducted as follows : 
Milk was obtained from a healthy cow, using particular care to ! 
prevent outside contamination. F or this milk we are greatly indebted j 
to Doctor Schroeder and Mr. Cotton, of the Experiment Station, ; 
Department of Agriculture, Bethesda, Md. | 
In addition to the usual precautions, a cloth wet with bichloride i 
solution was placed under the cow, permitting only the teats to pro- j 
