94 THE CATTLE OF GREAT BRITAIN. 



and liable to break. Tinned iron pans are now more generally 

 used, and they are cbeap, strong, and satisfactory in use. They 

 should not exceed 2 Jin, depth, as a loss of cream ensues if the 

 milk stands in a deeper vessel. Another advantage in using 

 shallow metal vessels is that the temperature of the milk is 

 more rapidly reduced, especially if the vessels stand upon slate 

 or stone shelves. It is very important that this reduction of 

 temperature, say from 90°, at which it comes from the cow, to 

 about 60°, should be as rapid as possible. It is, however, this 

 feature that makes the deep-setting system so valuable. A 

 rapid descent from 90^^ to 45® causes the cream to rise as fast 

 as possible. The fatty elements, having a less specific gravity 

 than the other portions of the milk, rise the more quickly, when 

 the fall in temperature is greater and more rapid, because the 

 fat feels the change of temperature first. Cream raised on this 

 cold system is always thin and larger in volume than that raised 

 in any other manner. Shallow pans, however, maintain a good 

 consistency in cream only when the temperature is equable and 

 temperate, and when this is the case the cream rises tolerably 

 quickly and before the skimmed milk is sour. By the deep 

 system, as by the separator, the skim milk is always sweet and 

 sound, and this gives it a special value. 



The invention of the cream separator marked an era in 

 dairying. By means of this machine milk brought in from the 

 cowshed at six o'clock in the morning can be deprived of its 

 cream, and sold sweet for breakfast, while the cream itself can 

 be churned and the butter made up for the same meal. The 

 skimmed, or as it is now called, the separated milk, is peculiarly 

 sweet and light from the aeration it has undergone, and for this 

 reason, as well as on account of its freshness, it ought to prove 

 an article of general and ready sale. In practice the cream, 

 however, is not churned for at least twenty-four hours after 

 separating, as it is too new. Sweet, fresh cream, neither makes 

 so much nor such ^ood butter, as cream which has been ripened. 

 In the ordinary way, cream skimmed from the pans is put into 

 a cream pot, and there it remains, every subsequent skimming 

 being thoroughly mixed with it by stirring until it is ripe, i.e., 

 until it has commenced to sour. Souring, however, must not 

 go too far. Eipe cream produces butter with a fuller and better 



