4 Testing Milk and Its Products. 



5. Introduction of milk tests. The first method 

 which fulfilled all reasonable demands of a practical 

 and reliable milk and cream test was the Babcock test, 

 invented by Dr. S. M. Babcock, of the Wisconsin agri- 

 cultural experiment station. A description of the test 

 was first published in July, 1890, as bulletin No. 24 of 

 that Station, entitled: A new method for the estimation 

 of fat in milk, especially adapted to creameries and 

 cheese factories. This test, which is now known in all 

 parts of the world where dairying is an important in- 

 dustry, was not, however, the first method proposed for 

 this purpose which could be successfully operated out- 

 side of chemical laboratories. It was preceded by a num- 

 ber of different methods, the first one published in this 

 country being Short's method, invented by the late P. 

 G. Short, and described in bulletin No. 16 of Wisconsin 

 experiment station (July 1888). 



6. Short's test. In this ingenioua method, a certain quan- 

 tity of milk (20 cc.') was boiled with an alkali solution and 

 afterwards with a mixture of sulfuric and acetic acids; a layer 

 of insoluble fatty acids separated on top of the liquid and was 

 brought into the graduated neck of the test bottles by addition 

 of hot water; the reading gave the per cent, of fat in the sam- 



. pie of milk tested. 



Short's method did not find very wide application, both be- 

 cause it was rather lengthy and its manipulations somewhat dif- 

 ficult for non-chemists, and because several other methods were 

 published shortly after it had been given to the public. 



7. Other milk tests. Of these may be mentioned, besides 

 the Babcock test already spoken (ft, the Failyer and Willard 

 method,'' Parsons' method,' Cochran's test,* the Patrick or Iowa 



1 See 48, footnote. 



" Kansas experiment station report, 1888, p. 149. 

 ' N. H. experiment station report, 1888, p. 69. 

 *,Tournal of Anal. Chem., Ill (1889), p. 381. 



