SAMPLING AND TESTING CREAM 73 
sample is used, and reduces the error in reading by one- 
half. The small bore of the neck also lessens any error in 
reading the test. 
In testing cream with this bottle, add 9 grams of 
cream, 9 c.c. of water, 17.6 c.c. of sulphuric acid and 
proceed with the test in the usual way, remembering that 
the fat column gives the reading for an 18 gram sample. 
Preparing the Sample. Before weighing the cream on 
the balance, care should be taken to thoroughly mix the 
sample by pouring and repouring a few times. Should 
the samples show any dried or churned cream, the sample 
jars must be placed in water at a temperature of about 
110° F. until the lumps of cream or butter have melted. 
When this is done the sample for the test bottle must be 
taken instantly after mixing, as the melted fat separates 
very quickly. In general, warming the sample jars some- 
what before sampling by placing them in warm water 
will facilitate the mixing and sampling of the cream. 
Making and Reading Cream Tests. The different 
steps in testing cream are essentially the same as in testing 
milk. However, as already stated, the cream must be 
weighed and tested in a special bottle. Furthermore, 
special precautions must be used in reading the test. 
It is well known that reading the extremes of the fat 
column gives too high a reading. This error is due to 
the meniscus at the top of the fat column the size, of 
which varies with the width of the neck. Farrington 
and Woll recommend reading from the lowest extremity 
of the fat column to the bottom of the upper meniscus. 
This is the method commonly employed in reading tests. 
Eckles and Wayman recommend removing the meniscus 
by adding a small quantity of amyl alcohol (colored red) 
