American Tests 89 
milk. In the next two years no less than seven dis- 
tinct methods were devised by chemists of Agricul- 
tural Experiment Stations for this. purpose. All of 
them were much better than any that had hitherto 
been known, but one was so much in advance of 
any of the others that now it is practically the only 
method used for the quick determination of fat in 
milk. This is the method devised by Dr. S. M. Bab- 
cock, known as the Babcock test, and first published 
in July, 1890. The various tests, in the order of 
their publication, were as follows: 
Short’s method.—This method was invented by 
F. G. Short, at that time chemist of the Wisconsin. 
Agricultural Experiment Station, and was first pub- 
lished in Bulletin No. 16 of the Wisconsin Agricul- 
tural Experiment Station for July, 1888. In brief, 
the method consisted in converting the fat in the 
milk into a soap by means of an alkali, and then dis- 
solving the soap by an acid, setting free the fat. 
The process was rendered complete by boiling for 
several hours. The determination was made with a 
measured quantity of milk in a glass test bottle with - 
a narrow graduated neck, into which the fat was 
raised at the end of the process and. read off volu- 
metrically. Considerably difficulty was often ex- 
perienced in getting a clear separation of the fat 
from the contents of the tube. The long period of 
boiling was also an important drawback to the 
method. 
The method of Failyer and Willard.—This method 
was devised by Professors Failyer and Willard, of 
