CHAPTER XV. 



ON THE MILK OF THE COW AND THE SOLID EXCREMENTITIOUS MATTER, 

 AS AFFECTED BY FOOD AND TEMPERATURE, OR THE SEASON. 



The experiments which I am about to give, in detail, were undertaken for the purpose of ascer- 

 taining the influence of food on the quantity and quality of the milk of the cow, especially upon 

 the quantity of butter which the winter's milk contains. In undertaking this task, I am aware 

 that cows differ materially among themselves, both as it regards the quantity and quality of 

 their milk. It has not, however, been so well established that the winter milk differs from 

 that of summer, which I believe I am justified in stating. I was the more desirous of under- 

 taking these experiments from the fact that, so far as I am informed, no experiments of the 

 kind have been undertaken in this country, which have been accompanied with the necessary 

 analyses. So also, the universal use of the milk of the cow makes it an important subject for 

 investigation : the young of all mamiferous animals are fed upon it, and it contains, in its 

 hfalthy state, all the elements of nutrition, in the proper proportion to supply the materials of 

 growth*: it is the standard from which we may derive important rules for regulating our own 

 diet. We may infer that, as it is the nutriment prepared for the young, it must contain not 

 only the proper elements of support, but also the proportion and combination best adapted to 

 the wants of the living system. It must also be obvious, upon a moment's reflection, that the 

 milk of animals will differ. The flesh feeder will secrete milk whose properties will differ 

 somewhat from the vegetable feeder. Taking the classes of animals by themselves, no one 

 would be surprised to find their milk differing in the proportion of its elements. Let us look 

 at this subject for a moment, taking the analyses of the most distinguished chemists in this de- 

 partment of science. The late Frank Simon gives us the following analyses of the milk of 

 animals : 



Cow. Ass. ' Goal. Ewe. Bitch. 



Water 857-0 916-3 868-0 856-2 657-4 



Solid matter, 143-0 83-5 42-0 342-6 



Butter 40-0 1-1 33-2 42-0 162-0 



Casein, 72-0 18-2 40-2 41-0 1740 



Sugar and extractive matter 28-0 60-8 52-8 42-0 29-0* 



Salts, 6-2 3-4 5-8 15-0 



'Only a trace of sugar, mostly extractive matter. Taste, saltish and mawkish; odor, unpleasant. Simon. 

 [AoBICtJLTURAI. ReFOBT VoL. HI.] 40 



