New York AGRICULTURAL EXPERIMENT STATION. 215 
subtract the cost of food eaten by the animals, we obtain the ap- 
proximate amount of profit. However, when the milk is taken 
from the farm and no part retained in any form, a certain amount 
of food and fertilizing material is removed, which the dairyman 
must replace in some form. To illustrate, when we sell and carry 
away from the farm 1,coo pounds of average milk for $12.50, we 
take from the farm materials which have a food and fertilizing 
value of 25 cents for each 100 pounds of milk or $2.50 for the 
1,000 pounds of milk. By retaining the skim-milk and buttermilk 
and selling only the fat in the form of butter, we could secure the 
same amount of money for 1,000 pounds of milk and still retain 
on the farm the materials which are worth $2.50 for food and 
fertilizer. Therefore, when we take the milk from the farm, we 
must, for each 1,000 pounds, pay out from the money received $2.50 
to replace the food and fertilizing materials sent away in the milk, 
if we are to keep the farm and animals in the same condition we 
should were we to retain on the farm the skim-milk and buttermilk. 
In theory, then, at least, of the $12.50 received for the milk, we 
must pay out $2.50 to buy food and fertilizer to take the place 
of that removed in the milk sold, and the actual profit derived from 
selling 1,000 pounds of milk would be $2.50 less than the apparent 
profit. 
In regard to the actual market value, skim-milk can be purchased 
at creameries for 1214 cents per 100 pounds or one-half of what 
we usually rate it for in theory. Since this is so, it will represent 
actual results more closely, if we deduct the latter amount in de- 
termining actual profits. 
We have, therefore, presented tabulated results showing the ap- 
parent and actual profit derived from selling milk. In determining 
the amount of money to be deducted for feeding and fertilizing 
values, we use the solids-not-fat as a basis for calculation, because 
the skim-milk of different breeds varies in both feeding and fertiliz- 
ing value. We deduct the amount of. fat which would in butter- 
making go into butter, from the entire yield of milk solids. The re- 
maining solids, mostly waste fat, would have a theoretical value of 
about three cents a pound, but a market value of only half this, since, 
as pointed out above, skim-milk can be purchased at about one-half 
of its real feeding and fertilizing value. By using the solids as a 
basis of determining the value of the skim-milk, we secure results 
that represent the truth more nearly than we should if we rated all 
the skim-milk at the same price per 100 pounds, regardless of com- 
position. 
