284 ILLINOIS STATE DAIRYMEN'S ASSOCIATION. 



This simple experiment proved the correctness of the theory 

 of separating milk from cream by centrifugal force. 



Soon after German investigators constructed a vessel to re- 

 volve upon its own vertical axis, in which the milk to be sepa- 

 rated was placed. This machine was set in motion, and again 

 when the proper speed was attained the separation was found 

 to be complete. When the separator came to rest a fresh sup- 

 ply of milk was placed in it and the operation repeated. 



The difficulty connected with this machine was that with 

 each lot of a few hundred pounds of milk the machine had to be 

 stopped and started, thus occupying much valuable time. 



The problem which now presented itself was to construct a 

 device or attachment to this separator by which a constant sup- 

 ply of new milk could be run into it and the separated products 

 be removed without injury while the machine was in motion. 

 Many plans were used and attachments tried, but none were 

 entirely successful until Dr. De Laval, of Stockholm, Sweden, 

 conceived the idea of attaching a pipe directly to the separator 

 that would revolve with the bowl, and at the same time carry 

 off the skim milk as fast as it was produced. 



A much more difficult problem was the discharging of the 

 cream in such a manner that it would not be injured. This has 

 been accomplished in but one separator as yet. In the machine 

 I refer to the cream is allowed to flow over the edge of the sep- 

 arating bowl in a very fine stream ; the air acts as a cushion 

 upon this stream and brings it to a gradual standstill, when it is 

 caught in a pan especially adapted for the purpose. 



About the same time that Dr. De Laval was making his 

 investigations, a firm in Denmark were also experimenting upon 

 the line of skimming the milk and cream from the separator by 

 means of sharp-pointed tubes, so arranged as to take up the 

 products of separation from the inner periphery of the moving 

 bowl. These experiments were further continued by Mr. Wes- 

 ton, of Boston, Mass., and the outcome was the present Danish- 

 Weston centrifuge or separator as it known in this country. 



