Farm Dairying 



249 



into milk rich in butter-fat. Creameries and dairies 

 pay for milk according to the per cent of butter-fat, 

 and not the mere gallons of milk. (See Fig. 124.) 



352a. (a) Farmer "A" runs a small butter dairy. He bought 

 a Babcock Test, and made a test of each cow's milk with the fol- 

 lowing results: 



Calculate the amount of butter-fat in each cow's milk. One 

 pound of butter-fat is equal to one and one-sixth pounds commer- 

 cial butter. How much butter would these cows make in ten 

 months? 



353. Other Uses of the Babcock Test. Creameries 

 no longer buy milk by the "gallon," but pay so much 

 a pound for the butter-fat. This does away with the 

 temptation to water the milk. In cities, public dairies 

 are required to sell pure milk, with a certain amount 

 of butter-fat, usually not less than 3.5 per cent. By the 

 use of the test, both the dairyman and the public offi- 

 cials may easily know if the milk is up to the required 

 standard of richness. The butter in buttermilk is often 

 a source of considerable loss. By testing the buttermilk, 

 or skim-milk, the dairyman may know if his methods 

 get all the butter. 



354. Composition of Milk. Milk contains about 87 

 per cent water and 13 per cent solids, divided as fol- 

 lows: 5 per cent sugar, 3.3 per cent protein, 4 per cent 



