320 DOMESTIC ANIMALS 



they seldom exceed forty inches. As a milk producer the Kerry 

 ranks very high not only in quality but also in quantity. On ac- 

 count of its ability to subsist on poor and scanty feed the Kerry 

 is sometimes called the poor man's cow. 



Dairying. Milk is a model food which furnishes every element 

 necessary for the nourishment of the body, and it is cheaper and 

 more economical than the equivalent amount of any other kind 

 of food. 



The chief dairy products are milk, cream, butter, and cheese. 

 Besides these there are several important by-products, such as 

 skim milk, buttermilk, and whey, which add to the profits of 

 dairying. Formerly our entire supply of butter and cheese was 

 made on the farm, but now these articles are furnished us from the 

 creameries and factories. 



Much of the value of these articles will depend on the quality 

 of the milk from which they are made. This is determined by 

 sampling the milk and ascertaining the amount of butter fat 

 present by means of a Babcock milk tester. 



The old method of separating the cream from the milk depended 

 on the action of gravity. The milk was placed in a vessel of any 

 kind and was cooled rapidly to a temperature of 60 F. and was 

 left undisturbed from twenty-four to thirty-six hours. The 

 fat globules, being lighter than the other constituents of the milk, 

 rise to the top and form a layer of cream which may be skimmed 

 off without difficulty. When this process is carried on in shallow 

 pans, we have what is known as the shallow setting of cream. 

 When the milk is placed in cans fifteen to twenty inches deep and 

 set in vessels of water kept at a temperature of 40 or less for 

 twelve to twenty-four hours, we have what is known as the deep- 

 setting system. By the shallow-setting system only about 75 

 per cent of the butter fat is saved, while by the deep-setting system 

 from 80 to 90 per cent of the butter fat is saved in the cream. 

 In the centrifugal separator the milk is passed into a revolving 

 bowl, where the skim milk, being the heavier, is forced towards 

 the outside of the vessel, and the cream, being the lighter liquid, 

 flows towards the center of the vessel. As the skim milk reaches 

 the outer edge of the vessel it passes into openings of small 

 tubes which convey it to an outer vessel. The cream passes into 



