MILK TESTING. 29 
during the whirling. Steam turbine testers should always be 
provided with a steam gauge or a speed indicator which will 
show whether the speed required for the particular tester is 
maintained. 
60. Reading the Fat. 
The column of fat should be read from the bottom line, 
where it meets the water, to the highest point where it joins the 
glass. The upper surface is curved, and quite often the test is 
read low by reading only to the lower part of the curve. It 
should be read as high as the fat goes in testing milk. The same 
thing applies when reading tests of whey. It is quite often read 
two-tenths when four-tenths is the amount present. A pair of 
dividers will aid in measuring the fat. Open them to the full 
length of the fat column, then place the lower point on the zero 
line, and the upper point will show the per cent present at a 
glance. When reading without dividers, errors in subtraction 
may occur. (See Fig. 14.) 
, Cin it 
Qa bl 
Sm Hi 
Fig. 15.—Test bottle 
for cheese and cream. Fig. 17.—Troemner halance, for testing cheese. 
Skim milk test bottles with specially narrow necks may be 
used in testing whey as well as skim milk. 
