CATTLE. 247 



Laboratory Apparatus for Complete Equipment in Studying 

 Dairy Problems. 



1. Scales for weighing milk and its products. 



2. A Babcock milk tester, with test bottles acid measure, sulphuric 

 acid bottle, 17.6 c. c. milk pipette, brush for cleaning and 

 cleansing test bottles. 



3. A milk cooler. 



4. Milk bottles or jars and test tubes for keeping samples of milk. 



5. A cream separator, and a churn. 



6. A thermometer and a microscope. 



7. Preservatives to prevent souring of milk. 



A Good Bulletin. 



Circular 122, Testing the Dairy Cow. Ohio Agricultural. Experiment 



Station, Wooster, O. 

 See Bulletin on Equipment. 



Exercises. 



1. Let each pupil bring a sample of fresh morning's milk from 

 home. 



2. Make a test of evening's milk from same cow. Compare the 

 test of morning and evening milkings. 



3. A composite sample covering four consecutive milkings is neces- 

 sary for a fair test. A test covering a week's milking is better. 



4. Find out how many owners of cows in your district keep a 

 dairy record. 



0. Get records of individual cows. Compare different dairy records. 



6. Get the opinions of owners who have studied cows. 



7. Keep all data for reference. 



8. Compare cost of feeds, cost of cows, production and profits. 



9. Compare the Babcock Tester with the Cream Separator. 



10. Compare weight of skim-milk with weight of cream. 



11. Why does cream come to the top? 



12. What is centrifugal force? 



13. Explain the cause of cream or butter-fat coming to the top of 

 the test bottle in the Babcock test. 



14. Explain how the cream is separated from the milk by the cream 

 separator. 



Experiment. 



1. Prepare at the same time, a quart of each, sterilized, pasteurized 

 and untreated milk ; note difference in taste after 12, 18, 24 and 48 hours. 



2. Take milk at temperature of milking time, cool one quart to a 

 temperature of 40 Fahr. ; let the other quart stand without cooling. 

 Taste and note flavor of each at end of 6, 10, 18, 24 hours. 



