A gummy exudation from the stem and branches of Acacia Senegal (Acacia Verek), and from other species of Acacia.

Characters. - In roundish tears usually from half an inch to an inch in length, nearly colourless, brittle, and opaque from numerous minute cracks, or in angular fragments with shining surfaces. Bland and mucilaginous in taste; insoluble in alcohol, but soluble in water. The aqueous solution forms with subacetate of lead an opaque white jelly.

Composition. - Arabin or arabic acid (gummic acid) combined with calcium, and, in smaller quantities, with potassium and magnesium.

Impurity. - Starch fraudulently added.

Test. - Should not give a blue colour with iodine.

Preparations containing Gum Acacia.

B.P.

Dose.

Mistura Cretae ..............................

.1-2 fl. oz.

" Guaiaci ............................

.1.2-2 fl. oz.

Mucilago Acaciae .............................

.ad lib.

Pulvis Amygdalae Compositus..

.60-120 gr.

,, Tragacanthae ,, ...

.20-60 gr.

Trochisci, in all.

U.S.P.

Dose.

Mucilago Acaciae ...........................

ad lib.

Syrupus Acaciae .........................

,,

Uses. - It is a useful demulcent in coughs or sore-throat, also in irritation of the stomach and intestines due to catarrhal inflammation. It is also serviceable in cases of irritant poisoning, and it has been employed as a masticatory. The mucilage is used to suspend powders.