
New York AGRICULTURAL E\XXPERIMENT STATION. 139 
Upon February twenty-fourth the experiment with Nellie gave, — 
as the average of the first three pints of milk, 9.37 per cent of 
solids not fat, and .786 per cent of ash, facts which prove that the 
difference in the successive portions of milk drawn were almost 
wholly in the relative amount of fat they contained. 
COMPOSITION OF MILK. 
The following table gives the average daily milk yield and the 
composition of the milk of the several breeds under investigation, 
and the percentage composition of the total solids of the milk. 
Tt will be seen that this table gives the average results from an 
ageregate of 930 analyses. 
Tt will be seen that while the average per cent of caseine in the 
milk of the different breeds varies from 3.39 to 3.91, or 15.3 per 
cent, the per cent of fat varies from 3.46 to 5.61 or 62.1 per cent, — 
while the sugar varies from 4.84 to 5.33 or 10.1 per cent, and the 
ash from .698 to .760 or 8.9 per cent. 
According, therefore, to the above table the ash varies least 
among the above constituents of milk, sugar next, then caseine, 
and fat, by far, in excess of all, varying over four times as much 
as caseine. This fact would clearly demonstrate that the per cent 
of fat present is the most reliable test by which to determine the 
relative value of normal milk not only for butter production but 
also for the manufacture of cheese. 
If, however, we consider the percentage composition of the 
total solids in the milk we find the variation to be somewhat 
different, since, as will be seen, the caseine varies from 24.7 to 27.4 
or 10.9 per cent, the sugar from 33.4 to 40.8 or 22.2 per cent, the 
ash from 4.82 to 5.92 or 23 per cent, and fat from 27.3 to 36.4 or 
33.3 per cent, or very appreciably more than either of the other 
constituents of the total solids. 
It is to be remembered that these results may differ as the 
animals become more mature, and ‘can only be urged as true for 
the first period of lactation; but the results thus far secured 
conclusively establish the fact that despite the great differences 
which we find in the individuals even of the same breed, there are - 
‘ marked differences which characterize the milk from the different 
breeds. 

