6 3 6 



MAIZE 



CHAP. 

 XIII. 



Apart from the commercial side of the business, the ideal 

 combination to produce the "fattest" balance sheet is the 

 best machinery, the best " flow sheet," and a thoroughly prac- 

 tical miller to work them ; unfortunately the last named is a 

 rara avis, comparatively speaking, in South Africa. 



590. Cleaning and Preparation. — The machine used first, 

 for the cleaning of maize, is the zigzag separator. This 

 consists of a number of sieves built in a frame in zigzag shape 

 (Fig. 214) (whence the name) and covered with perforated 



Feed Aspiration 



First 

 Screeninqs "• 

 Tip - 



Overtdils^, 

 y'Sieve' 



Feed 



/ Shoe 

 and Feed 

 Distributor 



*=^4 



Gram Delivery 

 Fig. 214. — Zigzag separator. (Courtesy of Messrs. Samuelson.) 



steel similar to those used in a wheat-cleaning machine, except 

 that the perforations are larger to suit the different types of 

 maize milled. It is operated by an eccentric shaft ; a large 

 fan is fixed on the frame, and the grain is subjected to a 

 strong air current on entering and leaving the machine. After 

 passing over a magnetic separator, which extracts any nails, 

 pieces of wire, or metal, the grain is fed into a special 

 "scourer" which polishes it and takes out any weevils if 

 old maize is being treated. 



If it is desired to turn out a high grade mielie meal for 

 table use, the grain is subjected to further treatment by- 

 passing it through a " steaming- worm," into which is con- 



