TABLE OF CONTENTS. 



PAGE. 

 Introduction 1 



Chap. I. COMPOSITION OP MILK AND ITS PRODUCTS . . 11 



Composition of milk: Water. Fat. Casein and albu- 

 men. Milk sugar (lactose). Ash. Other components. 

 Colostrum milk. Composition of milk products. 



Chap. II. SAMPLING MILK 23 



Sweet milk. Partially churned milk. Sour milk. Frozen 

 milk. 



Chap. III. THE BABCOCK TEST MILK 28 



A. Directions for making the test: Sampling. Adding 

 acid. Mixing milk and acid. Whirling bottles. Adding 

 water. Measuring the fat. 



B. Discussion of the details of the test: 



1. Glassware. Test bottles. Pipettes. "Fool pipettes." 

 Acid measures. The Swedish acid bottle. Calibration of 

 glassware. Calibration with mercury. Calibration with 

 water. The Trowbridge method of calibration. 



2. Centrifugal machines. Speed required for the com- 

 plete separation of the fat. Ascertaining the necessary 

 speed of testers. Hand testers. Power testers. 



3. Sulfuric acid. Testing the strength of the acid. The 

 Swedish acid tester. The color of the fat column an index 

 to the strength of the acid used. Influence of temperature 

 on the separation of fat. 



4. Water to be used in the Babcock test. Reservoir for 

 water. 



5. Modifications of the Babcock test. The Russian milk 

 test. Bartlett's modification. Siegfeld's modification. 

 Bausch and Lomb centrifuge. 



Chap. IV. THE BABCOCK TEST CREAM 74 



Measuring the cream. Cream-test bottles. The bulb- 

 necked cream bottle. The Winton cream bottle. Use of 

 milk test bottle. Use of 5 cc. pipette. Weighing the 

 cream. 



