50 MARKET DAIRYING 
Apparatus. This consists essentially of the following 
parts: A, Babcock tester; B, milk bottle; C, cream bottle; 
D, skim-milk bottle; E, pipette or milk measure; F, acid 
measures; G, cream scales; H, mixing cans; I, dividers. 
A. Babcock Tester. This machine, shown in Fig. 8, 
consists cf a revolving wheel placed in a horizontal posi- 
tion and provided with swinging pockets for the bottles. 
This wheel is rotated by means of a worm wheel (lower 
machine) at the top of the tester. When the tester stops 
the pockets hang down allowing the bottles to stand up. 
As the wheel begins rotating the pockets move out causing 
the bottles to assume a horizontal position. The wheel is 
enclosed in a cast iron frame provided with a cover. 
B. Mitk Bottle. This has a neck graduated to ten 
large divisions, each of which reads one per cent. Each 
large division is subdivided into five smaller ones, 
making each subdivision read .2%. The contents of the 
neck from the zero mark to the 10% mark is equivalent to 
two cubic centimeters. Since the Babcock test does not 
give the percentage of fat by volume but by weight, the 
10% scale on the neck of the bottle will, therefore, hold 
1.8 grams of fat. In other words, if the scale were filled 
with water it would hold two grams; but fat being only 
.9 as heavy, 2 cubic centimeters of it would weigh nine- 
tenths of two grams or 1.8 grams. This is exactly 10% 
of 18 grams, the weight of the sample used for testing. 
A milk bottle is shown in Fig. 9. 
C. Cream Bottles. These are graduated from 30% to 
55%. A 30% bottle is shown in Fig. 10. Since cream 
usually tests more than 30%, the sample must be divided 
when the 30% bottles are used. See page 71. 
