294 THE POTATO 



$6,000. These are based upon two distinct 

 methods of treatment. In the first, sliced po- 

 tatoes are exposed to the current of hot gases from 

 a furnace; in the second, the flake process, potatoes 

 are more finely divided, and dried at a lower tem- 

 perature with the aid of steam coils. This last 

 method is costly. The product of the first method, 

 while available for industrial purposes, is not fully 

 satisfactory for use as a fodder. 



"A process recently patented and introduced 

 by a Prussian firm seems to have successfully over- 

 come the disadvantages of the earlier systems. 

 The essential features consist in the use of pressure 

 combined with a vacuum for withdrawing the bulk 

 of the water in potatoes, the further drying of the 

 residue by artificial heat, and the isolation of 

 albumen found in the press liquor. This process 

 has been tried with excellent results on an indus- 

 trial scale. 



"The plant employed is comparatively simple. 

 The potatoes are first thoroughly washed in a large 

 vat provided with a stirring apparatus. Thence 

 they pass into a mashing machine, and the pulpy 

 mass is pumped into a reservoir, and from this is 

 fed through a large funnel into the suction machine. 

 The latter is the central feature of the plant and 

 presents a somewhat novel form of utilizing the 

 vacuum principle. It consists of two hollow cyl- 

 inders, one immediately above the other. The 

 exterior is made of perforated plate similar to that 

 employed in centrifugal machines and filter pumps, 

 and is covered with linen filtering cloth. A pipe 

 connects the interior of each cylinder with an air 

 exhaust. The interior spaces are, however, 

 divided into segments, and the construction is 

 such that the lessened pressure in each segment is 



