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The yield of raw flax, that is, the dry stems after the. retting 

 process, varies from f to i J tons per acre. About 80 per cent, 

 of this is removed in the breaking and scutching processes, 

 about 20 per cent. {i.e. 3 to 6 cwt.) remaining as fine scutched 

 flax. 



The seed obtained from a crop grown for fibre should not be 

 more than about 4 cwt. per acre ; when the crop is grown for 

 seed only, the amount produced varies from 8 to 1 1 cwt. per acre. 



Composition. — The seeds from the ripe capsule contain from 

 31 to 39 per cent, of linseed oil and from 19 to 25 per cent, of 

 nitrogenous substances, chiefly proteins in the form of large 

 aleuron-grains ; these reserve foods are stored both in the 

 endosperm and in the cotyledons of the embryo. 



The oil is used in the preparation of varnishes, oil-paint, and 

 printers' ink, for the manufacture of soft-soap and oilcloth, and 

 partially as food in some countries. 



The nitrogen-free extract, consisting of the mucilage of the 

 epidermis of the seed and hemicelluloses of the cell-walls of the 

 embryo and endosperm, averages 22 per cent., the amount of 

 water generally 12 per cent., the woody fibre 5 or 6, and the ash 

 about 4'3 per cent, of the seed. 



The residue of the seed, after extracting the oil, is made into 

 linseed 'oilcake,' the composition of which varies very much 

 according to the method adopted for extraction. 



Linseed cake of fair average composition usually contains from 

 II to 12 per cent, of water, 10 to 12 per cent, of oil, 28 or 29 

 per cent, of nitrogenous substances, 29 to 30 of carbohydrates 

 9-5 to II of fibre, and 77 to 8-8 per cent, of ash. 



