144 DAIRY FARMING 



2. Not enough acid. 



3. Too low temperature. 



Cleaning Test Bottles. As soon as the test is read, 

 the bottles are emptied by shaking them up and down so 

 as to remove the white sediment. Next wash them in 

 hot water containing some alkali, and finally rinse them 

 with hot water. Occasionally the bottles should be rinsed 

 with a special cleaning solution, which is made by dis- 

 solving about one ounce of potassium bichromate in one 

 pint of sulphuric acid. A small brush should also oc- 

 casionally be run up and down the neck of the bottle. 



Making and Reading Cream Tests. The different 

 steps in testing cream are essentially the same as in test- 

 ing 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) 

 to the top of the fat column. Farrington suggests add- 

 ing a few drops of fat-saturated alcohol to the top of 

 the fat as a means of removing the meniscus. Ordinary 

 alcohol has a solvent action on butter fat, hence the 

 necessity of using fat-saturated alcohol. 



Hunziker* after a thorough investigation of the sub- 



*Bulletin 145, Indiana Experiment Station. 



