LACTOMETER AND ITS USE 81 
1. Determine the percentage of fat in the sample under 
consideration. 
2. Determine its specific gravity. 
3. From the fat and specific gravity calculate the solids 
not fat and total solids. 
4. Compare the results obtained with the average 
specific gravity, per cent of fat, solids not fat and 
total solids given for normal cows’ milk, or compare 
with the legal State Standard. 
5. In drawing conclusions remember that 
Fat is lighter than water. 
Milk is heavier than water. 
c. Skimming increases the lactometer reading. 
d. Skimming slightly increases solids not fat. 
e 
f. 
mo. 
Skimming decreases fat and total solids. 
Watering decreases fat, solids not fat, lac- 
tometer reading and total solids. 
g. Watering and skimming decrease fat (ma- 
terially), solids not fat, and total solids. 
h. The solids not fat are less variable than the 
fat. 
i, Skimming and watering may give a normal 
lactometer reading. 
From i it is seen that a normal lactometer reading 
is possible when milk is skimmed and watered in the right 
proportions. A lactometer reading without a Babcock 
test is therefore worthless. 
For herd milk a lactometer reading above 33.5 is posi- 
tive evidence of skimming when accompanied with a low 
percentage of fat. Herd milk showing a lactometer read- 
ing below 28 is considered watered. 
Examples of milk adulteration in which only herd milk 
‘is considered are given as follows: 
