Cassiae Cortex. Cassia Bark.
Cassia bark is obtained from Cinnamomum Cassia, Blume (N.O. Laurineae), an evergreen tree indigenous to Cochin China, but growing also in other parts of Eastern Asia. The bark is collected from cultivated trees about six years old. The branches are cut off and freed from small twigs and leaves; longitudinal and transverse incisions are then made, and the bark stripped off in pieces about 40 centimetres long and half the circumference of the branch. The pieces are planed on the convex side, to remove most of the cork and part of the cortex, then tied up into bundles and packed in cases for exportation. The bark occurs in single quills or channelled pieces from 5 to 40 centimetres long, 12 to 18 millimetres in diameter, and 1 to 3 millimetres in thickness. It is of a dark, earthy-brown colour, with lighter patches of thin greyish cork. The fracture is short and granular. The odour resembles that of cinnamon, but is less delicate, the taste more mucilaginous and astringent. The bark differs from cinnamon in occurring in larger, thicker, darker pieces, and in single, seldom double quills.
Constituents.—The chief constituent of cassia bark is 1 to 2 per cent. of volatile oil. It also contains tannin, sugar, mucilage, and colouring matter.
Action and Uses.—Cassia bark has properties similar to those of cinnamon; it is mildly astringent, carminative, and antiseptic. Oil of cassia is used as a substitute for oil of cinnamon, which it closely resembles in its medicinal properties.