DAIRYING. 



less as to do more injury, by depressing the flavor and color, than it can do good by 

 increasing quantity. . \ 



"As fat, of which cream is mostly, composed, swells more with heat and shrinks 

 more with cold than water, of which milk is chiefly composed, it is evident that, if 

 other circumstances are alike, cream will rise better in a high temperature than in a 

 low one, since the fat in cream, by swelling more with heat, will be relatively lighter 

 when both milk and cream are warm than when both are cold, the temperature in 

 both cases neither rising nor' falling, but standing without change. Most people 

 seem to have the opinion that milk must be cooled to make the cream rise fast, and 

 that the colder they get it, the faster the cream will rise. The fact is exactly the 



Fig. 852.— Cross-breed Jersey — Ayrshire Heifer. 



reverse when the temperature is stationary,. The colder the milk, the Blower the 

 cream rises, because there is less difference between the specific gravity of the cream 

 and milk, and because the milk is more dense and offers more obstruction to the 

 motion of the cream globules. 



"In falling from a high temperature to a low one, the water in the milk shrink- 

 ing little and the fat much, the specific gravities come nearer alike, and hence the 

 fat rises more slowly at low temperatures than at high ones, when the temperature is 

 unvarying. Water is a better conductor of heat than fat ; hence, when the temper- 

 ature of heat varies either up or down, the water in the milk feels the effect of heat 

 or cold a little sooner than the fat in the cream does ; therefore the cream is always 

 a little behind the water in swelling with heat or shrinking with cold, thus dimin- 

 ishing the difference between the specific gravity of the milk and cream when the 

 temperature is rising, and increasing it when the temperature is falling. 



" The fact of a hurried rising of cream in a falling temperature of milk has a great 



