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ON THE MILK OF THE COW. 
It will be observed that milk derived from the sources referred to, is furnished with precisely 
the same elements, but these elements are combined in different proportion. To these analyses, 
I may add that of Simon’s analysis of the female of our own species. In this instance also the 
same elements exist, but their combination and relative proportion differ from the others, as 
will be observed by the following results : 
Water,. 883*6 
Solid matter,. 116*4 
Butter. 25*3 
Casein,. 34*3 
Sugar and extractive matter,. 48*2 
Salts,. 2*3 
Notwitstanding, however, the existence of this fact, the milk of our domesticated animals 
has been used extensively for the nutriment of our own species, without detriment or hurt. 
We have now seen what the milk is composed of, approximately ; three important substances, 
which differ materially from each other, and which, therefore, may be regarded as performing 
different functions in the animal economy, these are butter, cheese and sugar. 
The foregoing will serve to give the reader a general idea of the composition of milk. I 
considered that it was necessary that this statement should be first given, that the general idea 
of the milk of the cow might be well understood. We require this for the knowledge of the 
effects which food has upon the composition of the milk. W T hat the cow eats becomes both 
flesh, blood and milk; the system appropriates out of it so much as may be necessary for its 
wants. Now the animal has peculiar functions, and peculiar apparatus to fulfill these functions, 
each part having its office. The functions of some parts seem to be more chemical than others ; 
some border closely upon physical, as the separation and conveyance out of the body of the. 
excrementitious parts. 
The cow which I employed in the experiments is small, and of the variety called the Dutch 
breed, with short inturned horns; her color is red, with a few white spots along the back ; 
her weight, in November when at grass, was 890 pounds. Her calf, which was then seven 
months old, weighed 348 pounds. On being confined to the stable she ate from 21 to 27 
pounds per day of good hay. The average amount of hay for one week, during the last of 
November and first of December, was 155 pounds, or about 22 pounds per day. The water 
drank amounted, during the same week, to 298 pounds and 12 ounces, or a little over 42 
pounds per day. The solid excrements amounted to 309 pounds and 8 ounces, or a little over 
44 pounds per day. Her calf had given her the same kind of rations, at the same time, and 
ate of hay 85 pounds and 4 ounces in seven days, or about 12 pounds and 3 ounces per day, 
and drank during the time 120 pounds and 12 ounces of water, equivalent to 17 pounds per 
day; and made 144 pounds and 11 ounces of excrement, which is equivalent to 20 pounds 
per day. A large horse consumes 31 pounds of hay per day, and makes solid excrement to 
the amount of 82 pounds and 8 ounces for the same period. 
