272 BARKS 



lignea. Other species of Cinnamomum growing in the country between 

 these provinces of China and north-eastern India yield barks to 

 which the name of Cassia vera (or sometimes also Cassia lignea) is 

 given ; they are exported from Calcutta and Saigon. The cassia 

 vera of the London market is a firm, rather thick bark with a 

 very mucilaginous taste ; it is said to be the bark of (7. Burmanni, 

 de Candolle. 



The bark is collected entirely from cultivated trees. When about 

 six years old the branches are cut and all the small twigs and leaves 

 are stripped off ; two longitudinal slits are then made, and three 

 or four transverse incisions are cut round the circumference through 

 the bark at intervals of about 40 cm. The bark is then removed 

 in pieces about 40 cm. long and half the circumference of the branch. 

 These are next laid with the concave surface downwards and a small 

 plane passed over them, by which the cork and part of the cortex are 

 more or less completely removed. The bark is then tied up into 

 bundles and exported in boxes resembling tea chests, which are some- 

 times wrapped in bast-mats. 



Description Cassia bark is imported in bundles about 30 or 40 cm. 

 long and weighing about 500 grammes. The pieces of which the 

 bundle is composed vary from 5 or 6 to 40 cm. in length and average 

 from 1 to 2 cm. in width and 3 to 5 mm. in thickness. They are either 

 channelled pieces or single (but not double) quills, of a dark, earthy 

 brown colour and smooth, but with patches of the thin greyish cork 

 still adhering to the outer surface, indicating a want of care in trimming 

 them. 



The fracture is short, the section of the thicker pieces showing a 

 faint white line (sclerenchymatous cells) sometimes near the centre, 

 sometimes near the outer margin and parallel to it. In odour and 

 taste cassia bark resembles cinnamon, but it is less delicate in aroma 

 and more mucilaginous and astringent. 



Cassia bark occurs in much larger and thicker pieces than cinnamon, 

 seldom in double quills, and never packed into sticks. It is darker 

 in colour, and frequently exhibits patches of cork on the outer 

 surface. 



The student should observe 



(a) The thickness of the bark and its dark colour, 



(b) The patches of cork, 



(c) The characteristic odour and taste. 



Constituents. The constituents of cassia bark are similar to those 

 of cinnamon. It yields from 1 to 2 per cent, of volatile oil, resembling 

 that of cinnamon but having a higher specific gravity (1-050 to 1-070) 

 and containing more cinnamic aldehyde (75 per cent.) but no 

 eugenol. 



