LINSEED 151 



hardens to a varnish, a change due to the oxidation of the linolein. The oil is 

 characterised by its high specific gravity (0-930 to O940) and high iodine value 

 (not under 170). See also ' Linseed Oil.' 



The mucilage consists of a mixture of hexanes and pentanes corresponding 

 to the formula 2(C 6 H 10 5 ),2(C 5 H 8 4 ); it yields by hydrolysis the sugars galactose, 

 dextrose, arabinose, and xylose. 



Crushed linseed, Lini Semina Contusa, B.P., consists of the seeds reduced 

 to a coarse powder without being deprived of any part of their constituents. 

 It should, when mixed with water, have a bland, not pungent (cruciferous seeds) 

 or rancid (stale linseed) odour. It should yield not less than 30 per cent, of 

 oil to carbon disulphide (indicating the absence of ground cake left after 

 removal of part of the oil), and the oil thus extracted should respond to the 

 official tests for Oleum Lini. It should not give the characteristic reactions 

 with the tests for starch, nor leave, when incinerated, more than 5 per cent, 

 of ash (absence of added starch and undue proportion of mineral matter). The 

 presence of starch may be conveniently detected by microscopical examination 

 or by applying the usual iodine test to a cooled decoction of the crushed linseed 

 previously freed from oil by treatment with ether or carbon disulphide. 



Uses. Crushed linseed is used externally, in the form of a poultice, 

 to convey heat and moisture to certain parts ; the entire seeds are 

 used to make a demulcent infusion containing a large quantity of 

 mucilage. 



Note. Linseed usually contains foreign (weed) seeds, the proportion of which 

 should not exceed 4 per cent. ; these weed seeds often afford a guide to the 

 geographical source of the linseed. 



COLA SEEDS 



(Semina Colse) 



Source, &c. Cola seeds, sometimes called Cola or Kola nuts, Gooroo 

 nuts, or Bissy nuts, are obtained from Cola vera, Schumann (N.O. 

 Sterculiacece) , a large and handsome tree resembling in habit the 

 Spanish chestnut. It is a native of tropical Africa, growing wild 

 in Sierra Leone, North Ashanti, near the sources of the Niger River, 

 &c., but is cultivated in other tropical countries, such as the West 

 Indies, Brazil, Java, &c., our supplies being derived either from the 

 west coast of Africa or from the West Indies. 



The woody capsular fruit of the tree contains from five to fifteen 

 large white or crimson seeds which are removed and deprived of their 

 seed-coats, the kernels only being used. These are chewed whilst 

 still fresh, either before or after germination, and have been highly 

 valued by the negroes for many centuries for their stimulating 

 properties, in which they resemble tea, coffee, cocoa, &c. 



Large quantities of the seeds are collected and consumed by the 

 natives, who also carry on a considerable trade in them. Packed 

 in baskets with the leaves of the cola tree they can be kept fresh, and 



