New York AGRICULTURAL EXPERIMENT STATION. SEC 
The volume of milk adopted as « standard for the sake of com- 
paring the number of fat globules’ is one-ten-thousandth of a 
cubic millimeter, one cubic millimeter occupying about the 
volume of an ordinary pin-head. By using so small an amount 
of milk, we get numbers which are not too large to comprehend, 
and which answer satisfactorily for the purposes of comparison. 
The relative number of fat globules means, therefore, the number 
in one-ten-thousandth (.0001) of one cubic millimeter of milk. 
If we know the volume of fat and the number of globules in 
that volume, we can readily ascertain the average volume or size 
of one globule by dividing the volume of fat by the number of 
globules. Since we desire only relative numbers for the sake of 
comparison, it answers the purpose to take the per cent. of fat in 
the milk, obtained by analysis, as representing the volume of fat. 
If, then, we divide the per cent. of fat in the milk by the number 
of globules in .0001 cubic millimeters of milk, we shall obtain the 
average relative volume or size of one globule. As the number 
thus obtained is too small for convenient use, it is multiplied by 
10,000, and the number obtained is used to represent the relative 
size of the fat globules. The numbers representing the relative 
size of the fat globules do not, therefore, represent any actual 
size or volume, nor can they be referred to one standard of size ; 
but, by proceeding in the manner described with different milks, 
we get numbers which can be compared and which represent, 
relatively to one another, the average size or volume of the fat 
globules in the different milks. As pointed out by Doctor 
Babcock, the average diameter of globules would not serve well 
for comparison, unless the globules were uniform in size or nearly - 
so. “But as the volumes of spheres vary, not directly as their 
diameters, but as the cubes of their diameters, and as the average 
of a series of numbers does not determine what the average of 
their cubes will be, it follows, with bodies varying to the extent 
often occurring in the fat globules of milk, that their average 
diameter conveys no definite idea of their volume, which is really, 
in most cases, what is sought. The average volume of milk 
globules, owing to their variable size, is always greater than the 
volume indicated by their average diameter, the difference 
between two volumes being greatest when the globules vary most 
in size. It is, therefore, evident that if we wish to study the 


