166 AMERICAN DAIRYING. 



8. Keep the acid bottle corked when not in 

 use, because sulphuric acid takes up water from 

 the air and is thus diluted or weakened. 



9. When testing skim-milks and buttermilks 

 which have a very small per cent of fat (two- 

 tenths of one per cent or less) the reading of 

 the per cent of fat should be made immediately 

 on taking the test bottle from the centrifuge. 

 If this is not done and the test bottle cools be- 

 fore taking the reading the contraction of the 

 liquid in the bottle will leave the fat spread 

 over the inside surface of the measuring tube 

 so that it is not seen but has the appearance of 

 being only a dirty tube. If read when taken 

 from the machine the small fat globules can be 

 seen and estimated. 



The Babcock tested and proved. The Bab- 

 cock milk test was one of the things that made 

 a "ten-strike" at the World's Fair. It went 

 through a trial which gave it a very thorough 

 test. An understanding of the daily records 

 made by this test at the World's Fair ought to 

 convince any fair-minded person that the Bab- 

 cock milk test deserves the highest award. 

 Some who had previously expressed doubts 

 about its accuracy and practicability freely con- 

 fessed their conversion. The awards given in 

 the last or heifer test were based on the amount 

 of butter-fat found in the different cows' milk 

 by the Babcock milk tester. 



