4 Testing Milk and Its Products. 



therefore be done except in comparatively few cases, 

 with cows of great excellence or by farmers having 

 abundant hired help. 



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, chemist to the Wisconsin experiment 

 station. A description of the test was first published in 

 July, 1890, as bulletin No. 24 of Wisconsin experiment 

 station, entitled: A neic method for the estimation of fat in 

 milk, especially adapted to creameries and cheese factories. 

 This test, which is now known and adopted in all parts 

 of the world where dairying is an important industry, 

 was not, however, the first method proposed for this pur- 

 pose which could be successfully operated outside of 

 chemical laboratories. It was preceded by a number of 

 different methods, the first one published in this country 

 being Short's method, invented by Mr. P. G. Short and 

 described in bulletin No. 16 of Wisconsin experiment 

 station (July, 1888). 



6. Short's test. In this ingenious method, a certain 

 quantity of milk (20 cc. 1 ) was boiled with an alkali solu- 

 tion 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 sample of milk tested. 



Short's method did not find very wide application, 

 both because it was rather lengthy and its manipulations 

 somewhat difficult for non-chemists, and because several 



i See 48, footnote. 



