SEMEN LINI. 99 



11 to 12 percent., although i\t the same time its glycerin is destroyed by 

 oxidation. 



By saponification, linseed oil yields glycerin, and 9o per cent, of 

 fatty acids, consisting chiefly of Linoleic Acid, C'H'^O", accom])anied 

 by some oleic, palmitic, and myristic acid. The action of the air 

 transforms linoleic acid into the resinoid Oxylhioleic Acid, C"*H'*0\ 

 Linoleic acid appears to be contained in all drying oils, notably in 

 that of poppy seed. It is not homologous either with ordinary fatty 

 acids or with the oleic acid of oil of almonds, C'*H**0'. The chemistr}- 

 of the drying oils, especially those of linseed and poppy, has been parti- 

 cularly investigated by Mulder.^ 



The viscid mucilage of linseed cannot be filtered till it has been 

 boiled. It contains in the dry state more than 10 per cent, of mineral 

 substances, when freed from which and dried at 110' C. it corre- 

 sponds, like althrea-mucilage, to the formula C^-H^'^O^'^. The seeds by 

 exhaustion with cold or warm water afford of it about 15 per cent. 

 By boiling nitric acid it yields crystals of mucic acid ; by dilute mineral 

 acids it is broken up into dextrogyre gum and sugar and cellulose.- 



Linseed contains about 4 per cent, of nitrogen corresponding to 

 about 25 per cent, of protein-substances. After expression of the oil 

 these substances remain in the cake so completely that the latter con- 

 tains 5 per cent, of nitrogen, and constitutes a very important article 

 for feeding cattle. 



In the ripe state linseed is altogether destitute of starch, though 

 this substance is found in the immature seed in the very cells which 

 subsequently yield the mucilage. The latter ma}'^ be regarded as in 

 analogous cases to be a product of the transformation of starch. 



The amount of water retained by the air-dry seed is about 

 9 per cent. 



The mineral constituents of linseed, chiefly phosphates of potas- 

 sium, magnesium, and calcium, amount on an average to 8 per cent., 

 and pass into the mucilage. By treating thin slices of the testa and 

 its adhering inner membrane with ferrous sulphate, it is seen that this 

 integument is the seat of a small amount of tannin. 



Production and Commerce — Flax is cultivated on the largest 

 .scale in Russia, from which country there was imported into the 

 United Kingdom in 1872 linseed to the value of 3 millions sterling. 

 The shipments were made in about equal proportion from the northern 

 and the southern ports of Russia. 



The imports from India in the same year amounted in value to 

 £1,144,942, and from Germany and Holland to £144,108. The total 

 import in 1872 was 1,514,947 quarters, value £4,513,842. 



The cultivation of flax in Great Britain appears to be declining. 

 The area under this crop in 1870 was 23,957 acres ; in 1871, 17,36(5 

 acres ; in 1872, 15,357 acres ; and in 1873, 14,683 acres. The last- 

 named area reckoning the yield at 2 to 2| quartera of seed per acre 

 would represent a production of about 30,000 to 38,000 quartere. 



^ His numerous investigations on this Chemie der austrocknenden Oeh . . Berlin, 



subject have been published in a separate 1867, pp. 255. 



pamphlet, of which we have before us a ^ Kirchner and Tollens, Annalen dei- 



German translation : G. .J. Mulder. Die Chemie, 175 (1874) 215. 



