EXERCISE 43 



A STUDY OF THE GRAIN GRADER OR FANNING 



MILL 



Object. To study the structure of the grain grader, 

 and test its efficiency for grading grain for planting. 



Explanation. Small grain as it comes from the thresh- 

 ing machine is usually unfit for planting. It contains small 

 pieces of straw and chaff, which obstruct the grain drill in 

 seeding, and make uniform seeding impossible. Besides 

 straw and chaff, grain as it is threshed contains broken, 

 shriveled, and small kernels. This material is unfit for 

 planting, but will make valuable feed if separated from the 

 seed grain. 



It is estimated that twenty per cent of the grain as it 

 comes from the thresher is unfit for planting, but suitable 

 for feeding. By using the grain grader in preparing grain 

 for seed, a more uniform stand of vigorous plants is 

 obtained, and the broken and small kernels may be saved 

 for feed. 



Apparatus. 1. A fanning mill. 



2. A weight-per-bushel tester. 



3. One bushel of uncleaned wheat as it comes from the 

 thresher. 



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