158 SCIENCE OF SUCCESSFUL THRESHING. 



the cylinder and concave teeth to get the seed out of the 

 bolls. Usually six rows of concave teeth are required, and 

 the speed must be kept fully up to the 750 for the twenty- 

 bar or 1075 for the twelve-bar, but when dry and in good 

 condition, it is best to run the cylinder at a little less than 

 its normal speed to favor the shoe. Some very good samples 

 of cleaned flax have been taken from separators fitted only 

 with the adjustable sieves. Usually, however, it is necessary 

 to place a sieve underneath the adjustable shoe-sieve to do 

 first-class cleaning. For this purpose, the five-thirty-seconds- 

 inch round hole sieve, I, is the correct size. It should be 

 placed in the seventh notch at the fan end and the fourth 

 hole in the rear. This sieve should also be used in the 

 same position in the shoe of machines fitted with common 

 sieves. For an upper sieve, either of the wheat sieves may 

 be used, but the three-eighths-inch lip sieve, G, is preferable 

 to the fifteen-sixty-fourths-inch round hole sieve, H. For 

 a chaffer, the three-quarter-inch lip-sieve, F, works the best 

 of the common sieves. More wind can be used with two 

 sieves in the shoe than with one. 



Threshing Timothy. Although this seed when properly 

 ripened and cured, is not hard to thresh, it is often in such 

 condition as to render it very difficult for the separator to 

 handle. It is often cut and stacked when green or damp. 

 When in this condition, the bundles are very solid and they 

 must be properly fed or the cylinder and concave teeth may 

 give trouble. The speed, too, must be fully up to the normal, 



