1000 Rural School Leaflet. 



Most test-bottles are made to read as high as lo per cent. Each per- 

 centage has its number marked on the glass and there are five small 

 spaces each representing .2 per cent between these principal marks. 

 Thus, if the top of the fat column is even with the third short mark 

 above the 7 mark, the top reading would be 7.6; and if the bottom is 

 halfway between the first and second short marks above the 3 mark, the 

 bottom reading would be ^-S', the difference is 4.3, which is the percentage 

 of fat or number of pounds of fat in 100 pounds of the milk tested. 



Notes. 



I cc. means i cubic centimeter or about 20 drops. 



If the fat column is clouded with white specks, probably the acid 

 was not strong enough, or not enough was used, or the heat was not 

 high enough. 



If the fat column is clouded with dark specks, probably the acid was 

 too strong, or too much was used, or the heat was too great. 



Always keep the acid bottle closed when not in use or the acid will 

 lose strength. Remember that it is a poison and corrosive. 



Points to he Especially Noted in Making the Babcock Test 



H. E. Ross 



1. Be sure to mix the sample of milk thoroughly before drawing it 

 out with the pipette. 



2. When measuring a sample of milk with the pipette keep the index 

 finger dry. 



3. When measuring a sample of milk keep the mark on the pipette 

 on a level with the eye. The same precaution should be observed when 

 reading the percentage of fat after the test is completed. 



4. Do not try to measure a sample of milk by trying to draw the 

 milk just to the mark on the pipette. Draw the milk above the mark, 

 as directed. 



5. When adding milk or acid to the test bottle, slant the bottle. 

 The liquid will then run down the lower inside of the neck of the bottle, 

 and will not be forced out by outcoming air. 



6. Do not hold the bottle so that its mouth points toward yourself 

 or any one else. The action of the acid upon the milk produces great 

 heat. This heat often causes the contents of the bottle to spurt out 

 violently. 



7. After adding the acid to the milk, shake the bottle thoroughly 

 until the contents become dark in color. 



