668 
the physics of fluids, the top layers of the milk are sometimes not as 
hot as the bottom or require a much longer time to heat up. 
Experiment No. 1. 
Pint mixed market milk. 
Bottle immersed in water to its lip. 
Distinct cream line from standing over six hours before heating; thick cream, 
almost blitter, floating on top. 
Water 
temper- 
ature. 
1 
Milk temperature. 
Time. 
Colonies 
per loop 
in agar. 
Remarks. 
Top. 
Bottom. 
°a 
°C. 
°a 
Minutes. 
26 
26.5 
25.5 
(“) 
30 
26.6 
26.5 
2 
(“) 
40 
27 
28. 75 
4A 
(«) 
60 
30 
32 
7 
(a) 
60 
35 
39 
9 ^ 
(“) 
70 
41 
45 
12 
(«) 
75 
45 
49 
13 
(«) 
80 
50 
53.5 
14i 
(«) 
83 
Simmering. 
85 
55 
58 
15i 
(a) 
87 
58 
60.5 
16i 
(^) 
88 
60 
62.5 
16} 
(^) 
91 
63 
66 
17i 
(^) 
92.5 
65 
68 
18i 
(^) 
97 
70 
73 
19i 
(^) 
98 
71 
75 
20 
(^) 
Boiling. 
100 
75 
80 
2U 
(‘^) 
100 
78 
83 
23 
(<^) 
100 
80 
85 
23| 
(d) 
“ Innumerable.- ^ Distinctly less innumerable. 
Somewhat less innumerable. About 200,000. 
Experiment No. 2. 
Pint mixed market milk. 
Bottle immersed in water 6 inches, 1 inch out. 
Water 
temper- 
ature. 
Milk temperature. 
Time. 
Colonies 
per loop 
in agar. 
Remarks. 
Top. 
Bottom. 
°a 
°a 
°a 
Minutes. 
28 
14 
9,000 
60 
32 
5 
70 
40 
7 
80 
48 
9 
85 
50 
10 
8,000 
90 
65 
11 
4,000 
94 
60 
12 
750 
98 
65 
12i 
600 
100 
70 
13 
80 
