BABCOCK TEST: widely employed for determining the richness of milk and cream. The essential principle of the process is that sulphuric acid added in the proper proportion dissolves all components of the milk except the fat, permitting the entire fat content to rise to the surface to be measured. In creameries, to facilitate the process, the samples held in closed test-bottles, are, after the addition of the acid, agitated in centrifugal machines for some minutes before and after the application of a certain quantity of hot water.