THE NEW EARTH 



in the production of the world's dairy suppHes. 

 Indeed, even with the mechanical separation of 

 the butter-fat from the milk, modern dairying 

 could never have reached its present plane had 

 not an American, Dr. S. M. Babcock, of the 

 University of Wisconsin Experiment Station, 

 invented a machine for the determining of the 

 amount of butter in milk, without waiting for 

 the cream to rise or for the milk to be separated 

 from the cream. Dr. Babcock had long been 

 making investigations in the Une of the dairy, 

 when he one day hit upon a plan for testing 

 milk for its butter-fat. The device which he 

 made for the test, also, like most other impor- 

 tant inventions, a very simple affair, was merely 

 a tin receptacle like a pan in shape, with a cover 

 to it, on the inside of which were compartments 

 to hold several small bottles. By means of a 

 simple crank and wheel, the pan holding the 

 bottles could be made to revolve rapidly. 



He placed milk in the little bottles, along 

 with a small portion of sulphuric acid. This 

 acid would dissolve all the solids in the milk 

 save the butter-fat. When the pan was rapidly 

 revolved, the butter-fat was forced upward from 

 the milk into the narrow neck of the bottle, 



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