96 THE CATTLE OF GREAT BRITAIN. 



height (into a floor above for example) as it leaves the drum. 

 The speed with which milk is skimmed varies with the 

 temperature of the milk ; hence, the great advantage of 

 separating soon after milking, and when the milk remains at 

 about 76'' Fahr. 



Of the remaining system of obtaining the cream from milk, 

 the most popular is the cold deep setting system, known as the 

 " Swartz." This plan has many advantages where water of a 

 temperature not exceeding 45*^ can be obtained. A milk room 

 is not necessary, inasmuch as a large dairy of milk can be placed 

 in cans standing in a vat or tank of water about 6ft. by 2ft., 

 by 2ft. in depth. The cans are 16in. to 20in, in depth, by 6in. 

 to 7in. in width, the ends being rounded or oval in form. The 

 great secret is in subjecting the milk, when brought in hot from 

 the cows, to the sudden change of the cold water, by this means 

 the temperature rapidly falls, and the cream rises within twelve 

 hours, in time for the same cans to be washed and used for the 

 evening's milk. The system has many advantages. It permits 

 of the cream and skim milk being obtained perfectly sweet at 

 all seasons ; being covered, dust and insects are kept out. The 

 plant required is very small and lasting. Very little washing 

 is needed ; the cream is obtained quickly, and more butter is 

 obtained in the year than from milk set in shallow pans. 



The Cooley system somewhat resembles the above. The cans, 

 which are round, and generally about 20in. in depth by 8|in. 

 in diameter, being set in a refrigerator filled with water at 50°. 

 They are, however, entirely submerged, and, consequently, the 

 milk is free from all atmospheric influence. In both cases it is 

 usual to keep up a continual flow of water, and this is very 

 necessary in summer, especially with the Cooley. The cream is 

 not skimmed as in other systems, but the milk is drawn from 

 under it by means of an ingenious tap at the bottom of the can. 

 The disadvantage of the Cooley creamer is that it does not 

 receive the beneficial influence of the air, and that it is, 

 consequently, more difiicult to ripen the cream properly after 

 skimming. Like the Swartz, it occupies little space, is simple 

 and practical, but it is useless to adopt either, unless either 

 water, always sufiiciently cold, or ice, can be obtained. 



Another very important method of obtaining butter is by 



