FLAXSEED. J 03 



part of Africa ; has a dark colour, apt to contain impurities, less 

 abundant than the others. Guerin has discovered three distinct prin- 

 ciples in gum :— 1. Arahin — found in pure gum arabic, and which is 

 completely soluble in water. 2. Bassorin — found in Bassora gum; 

 characterized by swelling up considerably in water, but not dis- 

 solving. 3. Cerasin — found in the gum of fruit trees ; distinguished 

 by being converted into arabin by the action of boiling water. 



Uses. — Chiefly as a demulcent, in pectoral affections, diarrhoea, 

 and dysentery ; an ingredient in most cough mixtures; also in phar- 

 macy, in the compounding of pills. Mucilage for drink is made by 

 dissolving 5j in Oj of water. 



Tragacanth. — (Tragacantha, U. S.) 



Product of several species of Astragalus^ particularly of A. verus, 

 — small thorny shrubs growing in Persia and Asia Minor. The gum 

 exudes spontaneously. Occurs in irregular, tortuous pieces, of a dirty 

 yellowish colour ; translucent, resembling horn ; hard, but difficult 

 to pulverize ; consists chiefly of bassorin ; swells up, but does not 

 dissolve in water, — forms with it a paste. A demulcent, — used 

 chiefly in the preparation of troches. 



Slippery Elm Bark. — (Ulmus, U. S.) 



Inner bark of the Ulmus fulva^ a large indigenous tree. It is 

 stripped off in pieces several feet in length, and folded longitudinally. 

 Colour tawny ; texture fibrous ; odour peculiar ; taste sweetish, 

 peculiar and mucilaginous. It is a good demulcent, and is used in 

 dysentery, &c., also nutritious ; generally given in infusion. The 

 powder may be employed by simply stirring in boiling water, and 

 made of any thickness, and flavoured according to the taste. A 

 poultice made from the powder forms an excellent emollient appli- 

 cation to the inflamed skin. 



Flaxseed. — (Linum, U. S.) 



Seeds of the Lhium usitalissimum^ or common flax. They are 

 about a line in length, oval, of a brown colour, and flossy. The 

 cuticle abounds in mucilage ; the interior contains a fixed oil which 

 is procured by expression, and called Linseed oil — much used in 

 the arts. The mucilage is obtained by infusing the seeds in boiling 

 water ; not proper to boil them, since the oil would then be ex- 

 tracted, which is unpleasant to the taste ; — proportions, 3j to Oj 

 water, flavoured with lemon juice and sugar; — much used in pec- 

 toral and bowel affections, and nephritic disorders. The ground 

 seed forms with hot water an excellent emollient poultice. 



