83 The Cultivation and Preparation of Coffee 



is adjustable to suit various grades and varieties 

 of coffee. 



There is another system of coffee huller for 

 treating dry cherry coffee, this being the 

 ' ' Africa ' ' Huller. The only advantage I con- 

 sider worth mentioning in this machine, 

 referring particularly to the size I have seen 

 most in use that is, the No. 5 is its com- 

 pactness, the machine being combined with an 

 exhaust fan for the purpose of separating the 

 dust and shells from the cleaned coffee. This 

 machine treats the " bolita " very well, which 

 is the term given in Central America for those 

 dry cherries which only contain a peaberry each. 



In the ' ' Africa ' ' Huller the hulling takes 

 place between the steel ribs on the internal 

 cylinder and the adjustable knife or hulling 

 blade in front of the machine. The bottom of 

 the outer casing is sometimes perforated or at 

 times made of woven wire. The one is used 

 for treating dry cherry coffee and the other for 

 preparing parchment coffee before the polishing 

 operation. The bottom of the outer casing is 

 connected to the suction action of the fan, and 

 all the dust and shells passing through the 

 perforation or the open spaces of the woven 

 wire are drawn by the fan. 



In a plantation which I visited during my 

 last trip in Alta Verapaz I found a planter 



