ANALYTIC PROCESSES 
Specific Gravityx—The sp. gr. of milk rises 
gradually for some time after it has been drawn, 
and the determination isto be made only after 
this action has ceased. This will require about 
five hours after the milk is drawn, if it has been 
kept 15°, but at a higher temperature it will be 
necessary to allow at least twelve hours. For 
all other determinations the milk must be ana- 
lyzed as soon as possible. The following figures, 
published by Bevan, show that a considerable 
loss in total solids may occur in twenty-four 
hours: 
Totat Sotips = Loss 
Evaporated immediately ... 11.73 
Evaporated after 24 hours, 10.79 0.94 
Evaporated after 48 hours, 10.38 1.35 
Evaporated after 120 hours, 9.42 2.31 
The decomposition is very irregular, and it is 
not possible to determine, by estimation of the 
lactic acid or other products, the original compo- 
sition of the milk. 
Air-bubbles are held rather tenaciously by milk, 
and care must be taken in mixing, preparatory 
to taking the sp. gr., to avoid as far as possible 
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