READING TEST BOTTLES. 



309 



closer than 10 to 12, per cent spaces, per inch of 

 graduation. The bottles that are graduated to carry 

 6 to 8, per cent spaces, per inch are much to be pre- 

 ferred. 



Illustratiiw How to Read Cream Tests. 



88. The most accurate cream test bottles now 

 generally used are the 30 per cent, .18 gram, 6 inch, 

 % inch neck diameter; the 30 per cent, 18 gram, 9 

 inch, and the 50-55 per cent, 9 inch, 18 gram cream 

 test bottle. 



The reason why the reading of tests made from 

 the same lot of cream with differently graduated 

 cream test bottles is not always the same is mainly 

 due to inaccurate graduation of the bottle, irregu- 

 larity in the surface of the top and bottom of the 

 fat column and the inability to determine the proper 

 points on the graduation from which to read the 

 tests. "Were the fat column clear, with straight top 

 and bottom line, the reading could be accurately 

 done with any cream test bottle. 



