100 FLAX CULTURE AND PREPARATION 



When the fan is set in motion, the pressure of the wind 

 created, is sufficient not only to blow the chaff, but also the 

 seed, any distance. The pressure can, however, be so regu- 

 lated that when the seed falls by gravity from D into C the 

 heavy seed, still less affected by the fan than by gravity, 

 continues to fall direct on to the division G and gradually 

 finds its way down the shoot 0. Into the division H a lighter 

 class of seed is carried, and into the division I, a still lighter 

 seed and some chaff. Into the division K, the chaff is mostly 

 carried but into J only black chaff leaves dust, and the 

 lighter weed seeds are blown. With this arrangement, pro- 

 vision can easily be made for continually collecting the seed, 

 etc., from the separate divisions G H I J K. 



It is decidedly advantageous to separate the clean flax seed 

 into groups of different weights, to keep them distinct and to 

 sow them separately. 



Fig. 59 shows an arrangement for stacking the undeseeded 

 straw, through the winter, so as to be virtually out of reach 

 of vermin. 



