( 



502 TRANSACTIONS OF THE 



yield the most delicious, and the finest flavored is given by cows fed upon 

 clover, but that is universally the hardest from those feci upon dry food, 

 and that made in the fall of the year will keep the longest. The constitu- 

 tion of animals likewise affects the butter seriously, since there are some 

 w)iich with the choicest food give very inferior butter. In all cases the 

 quality is dependent upon the milk with which it is made, and the mode of 

 manufacture ; churn the same cream, and it will make different qualities by 

 different modes of procedure. The manner of extracting it, therefore, is 

 worthy of particular attention. The milk in the udder of the cow is not of 

 the same uniform quality ; that which is first drawn off is thin and capable 

 of giving but little cream, whereas that which is last drawn, is very rich, 

 and yields a large percentage of fine quality ; compared with the first drawn, 

 the same measure of the last, will give eighteen times as much cream, and 

 the milk is far better after the cream is taken off. I have noticed too that 

 the elobules in the first drawn milk are small and single, and that they 

 augment in size until those in the last drawn milk form twice the bulk, 

 and are double, having a smaller globule within each, covered with a shell 

 of casein of the thinnest imaginable texture, by which they are prevented 

 from running one into the other, and thus forming drops of oil. When 

 Mr. Johnson heats his cream, these globules immediately rise to the top, 

 press against each other in such quantities as to break their casein cover- 

 ings, and unite into a mass of melted fat, which ultimately collects in small 

 grains, and forms what we call butter, by the agitation it receives from the 

 rollers. 



In Russia cream is heated to one hundred and ninety degrees, and as it 

 cools, butter rises to the surface in the form of oil, and becomes solid, but 

 it has neither the proper flavor or consistence, and is chiefly used, instead 

 of oil, for culinary purposes. I do not know whether the scientific men of 

 this club have noticed the great difference that exists between young chil- 

 dren often seen in our streets, in nurses' arms — I have, particularly when 

 the nurses have appeared to enjoy equal health, and I could not account for 

 it, until recently, having two cows equal in size, giving the same quantity 

 of milk, both calving at the same time, both calves at birth very fine — still 

 at five weeks old, the one weighed twice as much as the other. Here arose 

 a philosophical question that puzzled me ; but on examining the milk of 

 the two animals, microscopically, the mystery; was explained. The globules 

 of one were more than twice the size of the other. If, therefore, you will 

 take the trouble, when next you see two similar nurses, with two similar 

 children, to examine their milk when the children are five weeks old, you 

 will discover the globules in one small, and the other large, accounting for 

 the difference in growth, health, size and strength of the two infants. I 

 throw this out as a hint for medical men, who generally select wet nurses 

 for their patients.* 



* Milk from !i womnn twenty years old, contains constituents far more solid than from a 

 woman thirty-five years old. Women possesring dark hair give inueb richer milk than light 

 bmired women. 



