THE DAIRY 193 



suited for butter-making, while from the milk of Ayrshire 

 cows the cream rises very slowly. 



Morning's milk is said to havelarger globules than evening's 

 milk. The change from dry winter food to pasture in spring 

 is said to increase the size of globules. 



Milk with large fat globules, though preferable for butter- 

 making, is not so well suited for cheese-making as that with 

 small globules. The number of fat globules per cubic millimetre 

 of milk has been estimated to vary from two to eleven millions. 



6. Other circumstances. — But even when all known disturb- 

 ing influences have been eliminated milk shows considerable 

 variation. There is little doubt that even the average composi- 

 tion of the milk yielded by a cow is dependent upon the indi- 

 viduality of the animal, and the proportion of fat in the milk 

 of any individual cow is often subject to enormous changes from 

 one milking to the next, even when the conditions are, so far 

 as is possible, kept constant. The writer suggested, some years 

 ago, that probably these variations were due to changes in the 

 mental condition of the animal — i.e., her relative contentedness 

 or otherwise with her surroundings, food, &c. — and though the 

 hypothesis has given rise to some ridicule and amusement, he 

 still adheres to the opinion. It is well known that sexual 

 excitement, for example, has a marked effect upon both the 

 composition and quantity of the milk secreted ; it certainly 

 seems probable that other mental influences should act in a 

 similar manner, though perhaps in a different degree. Enjoy- 

 ment of food, comfortable housing, freedom from fright or 

 annoyance, say by insects or dogs, and other circumstances 

 affecting the placidity of existence may very probably affect 

 the physiological processes going on in the cow, and thus have 

 an influence upon the composition and quantity of the milk 

 secreted. 



Milk of Other Animals.— The following table, compiled 

 from various authorities, gives the avera^'e composition of the 

 milk of other animals ; 



