120 



Mill- and Its Products. 



rious contrivances have been introduced in the bowl 

 to aid in the completeness of the separation or to 

 increase the capacity. These contrivances have been 

 of two general types : one to break up the wall of 

 milk, and so give the particles of milk and cream 

 a better chance to pass by one another in their 

 passage from the center to the outside of the bowl; 

 the other, a series of interruptions to the passage 



of the milk from 

 its entrance 

 at the c e n t e r 

 to the outside, 

 causing it to 

 travel a much 

 greater dis- 

 tance and be 

 subjected to the 

 tj^ centrifugal force 

 for a longer 

 time. These 

 contriva n ces, 

 while adding to 

 the complexity 

 of the machine, 

 have increased 

 the capacity 

 a n d the e ffi- 

 ciency of the 

 separation. The best known of these contrivances 

 are the so-called "Alpha" discs or plates, — a series 

 of cup -shaped plates, nearly filling the bowl of the 



Fig. 12. Section of separator bowl of "United 

 States ■' type. 



