FEED MILLS 239 



buhrs in a manner so they may be opened or closed 

 according to the fineness to which the grain is to be 

 ground. The buhrs should be attached to the shaft or 

 mill in such a manner that they will not wobble and thus 

 rub against each other under any condition whatever. 

 This device should also be made substantial enough and 

 accurate enough so the buhrs can be adjusted to almost 

 any fineness and not interfere with each other. In a corn 

 and cob grinder which is driven by a belt or tumbling 

 rod, the hopper should be divided and should have a feed 

 regulator so the ear corn and fine grain may be regulated 

 as desired. There should also be a regulating device be- 

 tween the crushing cylinder and grinding buhrs. This 

 is quite often effected by means of a lever and vibrating 

 shutter, the former receiving its motion from the main 

 shaft of the mill. 



339. Alfalfa mills are used in reducing alfalfa hay to 

 meal suitable for poultry and other stock. The mill has 

 a cutter which cuts the hay into short lengths before 

 passing to the buhrs. Alfalfa may be ground in the corn 

 mill if the hay is passed through a hay cutter first. To 

 grind successfully, alfalfa hay should be very dry. The 

 capacity of alfalfa mills varies from 50 to 100 pounds of 

 ground alfalfa an hour for each horse power used. 



340. Capacity of feed mills. The amount of feed 

 ground an hour depends largely upon the degree of fine- 

 ness of the ground meal and the condition of the grain as 

 to moisture. It is to be expected that a mill with new 

 sharp buhrs will have a much larger capacity than a mill 

 with worn buhrs. Where a good quality of meal is pro- 

 duced a mill should be expected to grind at least four to 

 five bushels of corn, or two to three bushels of oats an 

 hour for each horse power used. Grinding ear corn the 

 capacity will be one-third less. 



